IAU Symposium 299: Schedule at a Glance

Time Mon, 3 Jun Tues, 4 Jun Wed, 5 Jun Thurs, 6 Jun Fri, 7 Jun

845 Welcome

Session 1 Session 3 Session 5 Session 6 Session 8 Chair: Fischer Chair: Maddison Chair: Kenworthy Chair: Wilner Chair: Graham

Invited Review: Invited Review: Invited Review: Invited Review: Invited Review: 900 Beth Biller Zoe Leinhardt Jonathan Fortney Mark Wyatt Rosemary Mardling

940 Galicher Nordlund Tinney Macgregor; S Dawson; S

1000 Tamura Chiang Lawler; S Su Kraus

1020 poster highlights poster highlights poster highlights Haywood; S Wu 1030 coffee & posters coffee & posters coffee & posters 1040 Bonnefoy Farihi

1100 poster highlights poster highlights Vigan Espaillat Augereau 1110 coffee & posters coffee & posters 1120 Bowler; S Evans Marshall 1140 Maire Osorio Rogers Phillips Session 9 Panel discussion noon Morzinski Panel Discussion 1220 Nascimbeni Lunch Lunch Lunch 1240 Llama; S Student Awards 1300 Haynes; S

Session 2 Session 4 Session 7 Chair: Hughes Chair: Booth Chair: Kavelaars

1400 Invited Review: Invited Review: Invited Review: Sean Andrews Richard Alexander Roman Rafikov 1440 van der Marel; S Carpenter Lambrechts; S 1500 Anthonioz Murray-Clay Piso; S

1520 poster highlights poster highlights poster highlights END Free Time 1530 coffee & posters coffee & posters coffee & posters 1600 Qi Hasegawa Pudritz 1620 Duchene Kennedy Schlichting 1640 Menu; S Ireland Cossou; S 1700 Rodigas; S Kalas Dvorak Poster session Public Lecture Banquet 1930 - 2130 2000 - 2100 1900 - 2200 S = Student

2 IAU Symposium 299: Exploring the Formation and Evolution of Planetary Systems

Table of Contents

Schedule at a glance! 2 Welcome ! 4 General Information (VCC, internet, local info, special events)! 5 Local restaurants! 9 Daily Schedule!

! Monday 3 June! 11

! Tuesday 4 June! 12

! Wednesday 5 June! 13

! Thursday 6 June! 14

! Friday 7 June! 15 ABSTRACTS! 16-112

! Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets! 16

! Session 2: Transformative Interferometry & Protoplanetary Disk Imaging! 33

! Session 3: Building Planets in Protoplanetary Disks: Earliest Evidence! 40

! Session 4: Co-evolution of Disks and Planetary Systems! 51

! Session 5: Detailed Studies of Known Exoplanets and Exoplanet Systems! 61

! Session 6: Debris Disks as Signposts of Planetary Systems! 83

! Session 7: Models of Planetary Formation and Evolution! 97

! Session 8: Evolution of Planetary Systems! 106 List of Participants! 113

3 Welcome

Welcome to Victoria!

This symposium brings together experts on the growth of planetary systems in protoplanetary discs through their early evolution to the final systems we observe around main-sequence stars today. Our goal is to enhance the interaction between those who study the formation of planets and those who study evolved exoplanets—two communities who do not typically interact strongly due to differences in instrumentation. By bringing these two communities together, we hope to ask provocative new questions, stimulate new avenues of research, and encourage the formation of new collaborations.

It is our pleasure to welcome you to Victoria for what we hope will be a very rich meeting.

Local Organizing Committee Science Organizing Committee

Brenda Matthews (Chair) James Graham (Chair)

Mark Booth France Allard

Alice Chow Antonio Hales

James Di Francesco Paul Kalas

James Graham Matthew Kenworthy

Wesley Fraser Anne-Marie Lagrange

Raphael Galicher Doug Lin

JJ Kavelaars Bruce Macintosh

Christian Marois Sarah Maddison

Brenda Parrish Brenda Matthews

Gerald Schieven Dimitri Mawet

Amaya Moro-Martin

Ruth Murray-Clay

Don Pollacco

Didier Queloz

Motohide Tamura

David Wilner

We wish to offer a note of thanks to Chris Sasaki at the Dunlap Institute for all his efforts in designing and maintaining the webpage for the meeting.

4 General Information

Victoria Conference Centre Information

Registration: The registration desk, located outside the Lecture Theatre during the conference and in the Lower Pavilion during the opening reception, will be staffed for the duration of the meeting. If you require assistance with anything during the meeting, Alice Chow and Brenda Parrish will be available to assist you.

Meeting Rooms: The meeting rooms are all on Level 1 of the VCC. All talks, including the free public talk, will take place in the Lecture Theatre.

Posters: The posters are located in 3 different rooms off the lobby: the Saanich Room, the Oak Bay Room, and the Esquimalt Room. See the whiteboard at the registration desk for the room assignment for poster sessions. The sessions are also indicated on the room doors. Poster boards are clearly marked with poster IDs. Please place your poster on the board with your assigned poster ID (see List of Participants, pp.113-117). Student posters are so indicated.

Quiet Room: The Victoria Room is a smaller room available for general use should you require a quiet space. If this space is in high demand, we will initiate a sign-up sheet.

Internet Connections

There is free wireless throughout the VCC. To access the network, you will have to input an access code into the VCC page that will open when you start your browser. Choose the option “I have a code” and input IAUS299 as the access code. It is not case sensitive.

Banks

Most Canadian banks have branches along Douglas St. downtown just a few blocks up from the VCC. Heading north along Douglas from the VCC, you will find TD Canada Trust (at Fort St), BMO Bank of Montreal, CIBC (at View St), and Scotiabank (at Yates St).

Emergencies

The emergency number in Canada is 911.

Taxis

There are three major taxi companies in Victoria. All take credit and debit cards. Blue Bird Taxi! www.taxicab.com! 250.382.2222 Victoria Taxi! victoriataxi.com! 250.383.7111 Yellow Cab ! www.empresstaxi.com! 250.381.2222!

5 General Information

Student Awards

The LOC is pleased to offer awards for the best student talk and best student poster. We encourage all attendees to fill out a ballot for each award (these two ballots can be found in your name badge). To facilitate evaluation of the student presentations, all are clearly marked in the program and will be highlighted by session chairs and through signage for posters. We have included a 5-star icon next to each student abstract in the program so you can record your impressions as you see talks and view posters.

The ballots ask you to rank your top three talks and top three posters. We will assess points for each rank as follows: 9 points for top rank; 6 points for 2nd rank and 3 points for third rank. The student with the highest number of points will receive the award.

The ballots can be placed in the ballot box at the registration desk at any time. Please note that the last student talk is on Friday morning. We will announce the award winners at the end of the meeting. The winners do not need to be present to receive their award.

Special Events

Reception Sunday, 2 June, 7:00 - 9:00 pm

All attendees are welcome at the evening reception in the Lower Pavilion of the VCC. The pavilion is surrounded by scenic gardens and the picturesque backdrop of the historic Empress Hotel. All attendees will find a ticket for a free drink in their name badges, and an extra one will be included if you indicated you are bringing a guest.

Poster Session Monday, 3 June 7:30 - 9:30pm

A dedicated evening poster viewing session is scheduled to allow a significant amount of time to highlight the poster contributions at the meeting. There will be a bar open during the 2 hour session, and all registrants will find a ticket for a free drink in their name badges. Please note that there will be no food during the poster session, so please be sure to plan a meal for yourself before or after.

6 General Information

“Dinner at the Museum” Banquet Thursday, 6 June, 7 - 10pm

The conference banquet will be held at the Royal BC Museum, located across the street from the VCC. Highlights include the First Peoplesʼ Gallery and the Modern History Gallery. Participants will be free to wander the exhibits that detail the history and pre-history of British Columbia and Victoria, while enjoying catered delicacies. The cost to attend the banquet is CAD$90 per person. Those still wishing to attend the banquet should inquire at the on-site registration desk.

7 General Information

Public Talk Tuesday, 4 June 8-9pm

A free public talk by Debra Fischer will be held Tuesday evening in the VCC Lecture hall.

HABITABLE WORLDS: The Search Continues

We search for planets like Earth because we are interested in finding life elsewhere. One could counter that this view is myopic – that life might be silicon based or floating in methane clouds on worlds that are very different from our planet. We would have a difficult time recognizing life that is so fundamentally different from anything on Earth. Surely, our best shot is to search for what we know: carbon-based life inhabiting rocky planets awash with oceans of water. This search must focus on nearby stars because even familiar signatures of life, like oxygen rich atmospheres, will be easier to detect on planets orbiting the closest stars.

Twenty years ago, we did not know if exoplanets were rare or common. Today, we know that most stars harbor small rocky planets like the Earth. Paradoxically, we have not yet carried out a sensitive search for these planets around the nearest stars. As this search begins in the next few years, we will learn if life is rare or common.

Debra Fischer is a Professor of Astronomy at Yale University who began hunting for exoplanets in 1997 by measuring tiny wobbles in the velocities of stars. She has discovered hundreds of exoplanets, including the first known multiple planet system in 1999. Her worked helped to advance understanding of planet formation by quantifying correlations between the planets and the chemical composition of host stars.

From 2003 – 2008, she led an international consortium to carry out a search for planets around metal-rich stars; that project alone detected more than 50 new extrasolar planets. Some of the planets that Fischer has found transit in front of their host stars; for these lucky cases, the size and density of the planets can be measured and reveal an incredible diversity in the interior structure of unseen planets orbiting stars that are hundreds of light years away. She is the principal investigator for CHIRON, a high-resolution spectrometer commissioned in Chile at Cerra Tololo Observatory in June 2012 that is breaking the precision records in the search for exoplanets. She and her team are now at work designing a next generation instrument to find 100 Earths.

8 Guide to some local restaurants

Victoria boasts a high number of restaurants (second per capita only to San Francisco in North America), of which we highlight only a few below. The available tourist guide mentions even more. If you have a craving for something and none of those listed meets your needs, feel free to ask an LOC member for a recommendation.

Breakfast: Shine Cafe - Great Breakfast Spot (B-1)! 1320 Blanshard Street

Jam - Most creative Breakfast youʼll ever have (B-2)! 542 Herald Street

Cora Breakfast and Lunch - good breakfast selection. Also good for lunch! (B-3)! 850 Douglas Street

Lunch: Hernandez - Great Mexican selection. Good vegetarian selection (L-1)! 735 Yates Street

The Mint - Good general food selection with vegetarian options. Also good for dinner (L-2)! 1412 Douglas St

Noodle Box - Spicy Asian Food (L-3)! 818 Douglas Street

Samʼs Deli - Lunch Deli Sandwiches and Soups (L-4)! 805 Government Street

The Joint - Great Pizza, including vegetarian options! (L-5)! 1219 Wharf Street

The Pink Bicycle - Great burgers. Lines might be long (L-6)! 1008 Blanshard Street

Devour - Really good lunch takeout (L-7)! 762 Broughton Street

Dinner: PIG - Amazing Barbeque. NOT vegetarian friendly (D-1)! 1325 Blanshard Street

Azuma Sushi - Sushi joint (D-2)! 615 Yates Street

Red Fish Blue Fish - Amazing Fish Tacos! Also a good lunch choice (D-3)! 1006 Wharf Street

Yokohama Japanese Restaurant - overall good Japanese food selection (D-4)! 980 Blanshard Street

Sizzling Tandoor - Excellent Indian (D-5)! 637 Johnson Street

Nautical Nellies Steakhouse - Good seafood and steak selection (D-6)! 1001 Wharf Street

Siam - Excellent Thai Food, Good Vegetarian Selection. Can handle large groups (D-7)! 512 Fort Street

Spice Jammer - Another great Indian choice. Can handle large groups (D-8)! 852 Fort Street

Green Cuisine - Entirely vegetarian menu (D-9)! 560 Johnson Street

9 Guide to some local restaurants

Rebar - Best Vegetarian in Victoria (D-10)! 50 Bastion Square

Pescartoreʼs Fish House and Oyster Bar (D-11)! 614 Humboldt Street

Ferrisʼs Downstairs Grill and Upstairs Oyster Bar (D-12)! 536 Yates Street

Il Terrazzo - Best Italian in Victoria (D-13)! 555 Johnson Street

Brewpubs: Swanʼs - Great Beer, Live Music every night. Owned by UVic! (P-1)! 506 Pandora Avenue

Canoe Club - Decent beer, AWESOME patio. Really great food (P-2)! 450 Swift Street

Pubs: Sticky Wicket Roof Top - Pub food, great upper floor balcony (P-3)! 919 Douglas Street

Garrickʼs Head Pub - Best hole-in-the-wall in Victoria (P-4)! 1140 Government Street

Bard & Banker - A local favorite (P-5)! 1022 Government Street

Scan this icon with your smartphone to get more information about the above dining places.

10 Day 1:! Monday 3 June 2013

8:45 Welcome

Session 1: High Contrast AO Imaging: Latest Results in Direct Exoplanet Imaging Chair: Debra Fischer! Abstracts pp16-32 900 Invited Review Beth Biller Detecting and Characterizing Exoplanets via Direct Imaging: Past, Present and Future

940 Wide-separated planets frequency from the International Deep Planet Survey Raphael Galicher

1000 SEEDS: Strategic Explorations of Exoplanets and Disks with Subaru Motohide Tamura

1020 Poster Highlights Debra Fischer

1030 Coffee & Posters

1100 Final results of the NaCo Large Program - Probing the Occurrence of Exoplanets and Brown Dwarfs at Wide Orbits Arthur Vigan

S 1120 The Planets Around Low-Mass Stars (PALMS) High-Contrast Imaging Survey Brendan Bowler

1140 Search for cool extrasolar giant planets combining coronagraphic, spectral and angular differential imaging Anne-Lise Maire

Session 2: Peering into Circumstellar Disks: Transformative Interferometry & high res imaging Chair: Meredith Hughes! Abstracts pp33-39

1400 Invited Review Sean Andrews Observing the Hallmarks of Evolution and Planet Formation in Circumstellar Disks

S 1440 Triggered planet formation in action resolved gas and dust images of a transitional disk and its cavity Nienke van der Marel

1500 The VLT/PIONIER survey of T Tauri disks of the southern hemisphere Fabien Anthonioz

1520 Poster Highlights Meredith Hughes

1530 Coffee & Posters

1600 Observational Signatures of the CO Snow Line in Protoplanetary Disks Chunhua Qi

1620 HST Imaging of New Edge-on Circumstellar Disks in Nearby Star-forming Regions Gaspard Duchene

S 1640 TW Hydrae: multi-wavelength interferometry of a transitional disk Jonathan Menu

S 1700 High-Contrast LBT AO Images of Debris Disks at 2-4 microns Timothy Rodigas

19:30 SPECIAL EVENT: Poster session with bar

S = Student presentation

11 Day 2: Tuesday 4 June 2013

Session 3: Building Planets in Protoplanetary Disks: Earliest Evidence Chair: Sarah Maddison! Abstracts pp40-50

900 Invited Review Zoe Leinhardt The Story of Planets: Anchoring Numerics to Reality

940 Zooming in on Proto-Planetary Disks Aake Nordlund

1000 Planetesimal Formation Eugene Chiang

1020 Poster Highlights Sarah Maddison

1030 Coffee & Posters

1100 A Herschel View of Dust Evolution in Protoplanetary Disks Catherine Espaillat

1120 The DIGIT Key Program on Herschel: Minerology and Gas in Disks Neal Evans

1140 Substructure and Signs of Planet Formation in the Disk of HD 169142 Mayra Osorio

Session 4: Co-evolution of Disks and Planetary Systems Chair: Mark Booth! Abstracts pp51-60

1400 Invited Review Richard Alexander Planet Formation in evolving protoplanetary disks

1440 ALMA Observations of Low-mass Stars in the Upper Scorpius OB Association John Carpenter

1500 Clues to Disk Structure from the Distribution of Giant Planets Ruth Murray-Clay

1520 Poster Highlights Mark Booth

1530 Coffee & Posters

1600 Disk inhomogeneities and the origins of planetary system architectures and observational properties Yasuhiro Hasegawa

1620 The bright end of the exo-Zodi luminosity function and implications for disk evolution and exo- Earth detectability Grant Kennedy

1640 Orbital Motion and Multi-Wavelength Monitoring of LkCa15 b Michael Ireland

1700 HST/STIS imaging of Fomaulhaut: New main belt structure and confirmation of Fomalhaut bʼs eccentric orbit Paul Kalas

20:00 SPECIAL EVENT: Free Public Talk by Debra Fischer in the VCC Lecture Theatre

S = Student presentation

12 Day 3:! Wednesday 5 June 2013

Session 5: Detailed Studies of Known Exoplanets and Exoplanet Systems Chair: Matthew Kenworthy! Abstracts pp61-82

900 Invited Review Jonathan Fortney Highlights of Exoplanet Characterization

940 A decade and a half of Anglo-Australian Planet Searching Chris Tinney

S 1000 The Debaised Kuiper Belt: Our Solar System as a Debris Disk Samantha Lawler

S 1020 Planets and Stellar Activity: Hide and Seek in the CoRot-7 system Raphaëlle Haywood

1040 Properties of the young gas giant planet Beta Pictoris b Mikaël Bonnefoy

1100 Poster Highlights Matthew Kenworthy

1110 Coffee & Posters

1140 Characterizing the Demographics of Exoplanet Bulk Compositions Leslie Rogers

noon High-Contrast Imaging of an Exoplanet with Clio, the MagAO Infrared Camera Katie Morzinski

1220 Unveiling an exoplanetary Neptunian atmosphere through multiband transit photometry Valerio Nascimbeni

S 1240 The Shocking Variability of Exoplanet Transits Joe Llama

S 1300 Exoplanet Transit Spectroscopy of Hot Jupiters Using HST/WFC3 Korey Haynes

FREE AFTERNOON

S = Student presentation

13 Day 4: Thursday 6 June 2013

Session 6: Debris Disks as Signposts of Planetary Systems Chair: David Wilner! Abstracts pp83-96

900 Invited Review Mark Wyatt Debris discs as components of extrasolar planetary systems

S 940 A Resolved Millimeter Emission Belt in the AU Mic Debris Disk Meredith Macgregor

1000 Signposts of Multiple Planets in Debris Disks Kate Su

1020 Poster Highlights David Wilner

1030 Coffee & Posters

1100 Detailed model of the exozodiacal disk of Fomalhaut and its origin Jean-Charles Augereau

1120 Final Results of the Herschel Open Time Key Programme DUNES Jonathan Marshall

1140 Five Stars, Three Debris Discs and a Galaxy: Two Exceptional Debris Disc Systems Neil Phillips

Session 7: Models of Planetary Formation and Evolution Chair: JJ Kavelaars! Abstracts pp97-105

1400 Invited Review Roman Rafikov Planet Formation: Latest Constraints and Future Directions

S 1440 Rapid growth of giant planet cores by pebble accretion Michiel Lambrechts

S 1500 On the Minimum Core Mass for Giant Planet Formation Ana-Maria Piso

1520 Poster Highlights JJ Kavelaars

1530 Coffee & Posters

1600 Planet Formation and Evolution in Traps: Origins of the Mass-Period Relation Ralph Pudritz

1620 Shedding light onto the Building blocks of Planets: Solar System constraints on the initial Planetesimal Sizes Hilke Schlichting

S 1640 A possible origin of compact systems of hot Super Earths Christophe Cossou

1700 Collision parameters governing water delivery and water loss in early planetary systems Rudolf Dvorak

19:00 SPECIAL EVENT: “Dinner at the Museum” Conference Banquet, Royal BC Museum

S = Student presentation

14 Day 5:! Friday 7 June 2013

Session 8: Evolution of Planetary Systems Chair: James Graham! Abstracts pp106-112

900 Invited Review Rosemary Mardling Evolution of Planetary Systems

S 940 Constraining planetary migration mechanisms in systems of giant planets Rebekah Dawson

1000 The Impact of Stellar Multiplicity on Planetary Systems Adam Kraus

1020 Orbital structure of Kepler Planetary Systems Yanqin Wu

1040 Archaeology of Exo-Terrestrial Planetary Systems Jay Farihi

1100 Poster Highlights James Graham

1110 Coffee & Posters

Session 9: Merging the Picture Chairs: Bruce Macintosh & Ruth Murray-Clay

1140 Panel discussion ! Antonio Hales, Alycia Weinberger, Marshall Perrin, Rosemary Mardling, Alexander Krivov !

1230 Awarding of Student Presentations

1245 End of meeting Poster take-down

S = Student presentation

15 Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets

1.01!Invited Review Talk Beth Biller MPIA Hedelberg, Germany 1 Detecting and Characterizing Exoplanets via Direct Imaging: Past, Present, and Future The last 5 years have yielded the very first images of exoplanets, considerably advancing our understanding of the properties of young giant planets. In this talk I will discuss current results from ongoing direct imaging efforts as well as future prospects for detection and characterization of exoplanets via high contrast imaging. Direct detection, and direct spectroscopy in particular, have great potential for advancing our understanding of extrasolar planets. In combination with other methods of planet detection, direct imaging and spectroscopy will allow us to eventually: 1) fully map out the architecture of typical planetary systems and 2) study the physical properties of exoplanets (colors, temperatures, etc.) in depth. Direct imaging has offered us the first glimpse into the atmospheric properties of young high-mass (3-10 MJup) exoplanets. Deep direct imaging surveys for exoplanets have also yielded the strongest constraints to date on the statistical properties of wide giant exoplanets. A number of extremely high contrast exoplanet imaging instruments have recently come online or will come online within the next year (including Project 1640, SCexAO, SPHERE, GPI, among others). I will discuss future prospects with these instruments in terms of planet characterization and determination of statistical properties of exoplanets.

16 Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets

1.02!Contributed Talk Raphael Galicher University of Paris Diderot, France Christian Marois, Bruce Macintosh, Ben Zuckerman, & Travis Barman 1 Wide-separated planets frequency from the International Deep Planet Survey Our team has observed more than 300 nearby young stars with adaptive optics systems at Gemini (NIRI/NICI), Keck (Nirc2) and VLT (Naco). One unique aspect of our 12-year survey was the inclusion of a large sample of massive young AF stars that were neglected in previous surveys, as the contrast and target distances are less favorable to image planets and brown dwarfs. The HR 8799 multi-planet system is the most significant discovery of our campaign. Combined with the non-detection limit, this finding allows for the first time an estimate of the Jovians planet population at large separation (> 5 AU). During my talk, I will present the IDPS sample and the combined IDPS/GDPS/DISYNAS/NICI sample. I will explain the main steps of the dedicated data processing. I will then show images of the planets and brown dwarfs that we detected in the IDPS data. I will eventually present the results on the Jupiter-like planet frequency between 5 and 200AU, comparing with radial velocity predictions.

! 1.03!Contributed Talk Motohide Tamura University of Tokyo and NAOJ, Japan SEEDS/HiCIAO/AO teams SEEDS: Direct Imaging of Exoplanets and Their Forming Disks with the Subaru Telescope SEEDS (Strategic Explorations of Exoplanets and Disks with Subaru) is the first Subaru Strategic Program, whose aim is to conduct a direct imaging survey for giant planets as well as protoplanetary/debris disks at a few to a few tens of AU region around 500 nearby solar-type or more massive young stars devoting 120 Subaru nights for 5 years. The targets are composed of five categories spanning the ages of ~1 Myr to ~1 Gyr. Some RV-planet targets with older ages are also observed. The survey employs the new high-contrast instrument HiCIAO, a successor of the previous NIR coronagraph camera CIAO for the Subaru Telescope. We describe the outline of this survey and present its first three„ÄÄyears results. The survey has published ~20 refereed papers by now. The main results are as follows: (1) detection and characterization of the most unequivocal and lowest-mass planet via direct imaging. (2) detection of a super-Jupiter around the most massive star ever imaged, (3) detection of companions around retrograde exoplanet, which supports the Kozai mechanism for the origin of retrograde orbit. We also report (4) the discovery of unprecedentedly detailed structures of more than a dozen of protoplanetary disks and some debris disks. The detected structures such as wide gaps and spirals arms of a Solar-system scale could be signpost of planet. The statistics of wide-orbit planets in each category will be briefly mentioned.

17 Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets

1.04!Contributed Talk Arthur Vigan Laboratoire d'Astrophysique de Marseille, France 1 Gaël Chauvin, Mickaël Bonnefoy, Dino Mesa, Jean-Luc Beuzit, Jean-Charles Augereau, Beth Biller, Anthony Boccaletti, Mariangela Bonavita, Elisa Brugaletta, Esther Buenzli, Joe Carson, Elvira Covino, Philippe Delorme, Silvano Desidera, Anne Eggenberger, Markus Feldt, Janis Hagelberg, Thomas Henning, Anne-Marie Lagrange, Alessandro Lanzafame, Francois Menard, Sergio Messina, Michael Meyer, Guillaume Montagnier, Christoph Mordasini, David Mouillet, Claire Moutou, Laurent Mugnier, Sascha P. Quanz, Maddalena Reggiani, Damien Ségransan, Christian Thalmann, Rens Waters, & Alice Zurlo Final results of the NaCo Large Program - Probing the Occurrence of Exoplanets and Brown Dwarfs at Wide Orbits Over the past decade, a growing number of deep imaging surveys have started to provide meaningful constraints on the population of extrasolar giant planets at large orbital separation. Primary targets for these surveys have been carefully selected based on their age, distance and spectral type, and often on their membership to young nearby associations where all stars share common kinematics, photometric and spectroscopic properties. The next step after the first detections of planet mass companions around most favorable targets is a wider statistical analysis of the frequency and properties of low mass companions as a function of stellar mass and orbital separation. In late 2009, we initiated a coordinated European Large Program using angular differential imaging in the H band (1.66 µm) with NaCo at the VLT. Our aim is to provide a comprehensive and statistically significant study of the occurrence of extrasolar giant planets and brown dwarfs at large (5-500 AU) orbital separation around ~150 young, nearby stars, a large fraction of which have never been observed at very deep contrast. The survey has now been completed and we present the data analysis and detection limits for the observed sample, for which we reach the planetary-mass domain at separations of >~ 30 AU on average. Then we present the results of the statistical analysis that has been performed over the 75 targets newly observed at high-contrast and the archive sample of ~60 stars observed previously in other deep imaging surveys. We discuss the details of the statistical analysis and the physical constraints that our survey provides for the frequency and formation scenario of planetary mass companions at large separation.!

1.05!Contributed Talk ! ! ✩✩✩✩✩Student Brendan Bowler University of Hawaii, USA Michael Liu, Evgenya Shkolnik, & Motohide Tamura The Planets Around Low-Mass Stars (PALMS) High-Contrast Imaging Survey Previous direct imaging planet surveys have primarily focused on intermediate- and high-mass stars, revealing a handful of giant planets. Yet M dwarfs, which present more favorable planet-contrasts and make up over 70% of all stars, have largely been neglected, so little is known about the population giant planets at moderate separations (10-100 AU) in this stellar mass regime. We present results from a high-contrast adaptive optics imaging survey targeting newly identified nearby (<35 pc) young (<300 Myr) M dwarfs with Keck II/NIRC2 and Subaru/HiCIAO. Our most interesting discovery is a young companion at the deuterium-burning limit with a projected separation of ~50 AU. Regardless of its origin, this low-mass object offers a rare opportunity to study the properties and evolution of planet-like atmospheres in detail. Our follow-up near-infrared spectroscopy reveal a mid-L spectral type, signs of intermediate-surface gravity, and intriguing evidence of dust retention at low temperatures, similar to the HR~8799 planets. In addition, we have also found four young brown dwarf companions spanning 30-70 Mjup; two of these are members of the AB~Dor young moving group, and another will yield a dynamical mass in the near future. With a sample size of roughly 80 single M dwarfs and a mass sensitivity of ~3 Mjup at 10 AU, this program represents the deepest and most extensive imaging search for planets around low-mass stars to date.!

18 Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets

1.06!Contributed Talk Anne-Lise Maire Paris Observatory - LUTH, France Julien Rameau, Anthony Boccaletti, Gael Chauvin, Anne-Marie Lagrange, & Silvano Desidera 1 Search for cool extrasolar giant planets combining coronagraphic, spectral and angular differential imaging Spectral differential imaging is part of the observing strategy of current and on-going high-contrast imaging instruments on ground-based telescopes. Spectral differential imaging (SDI) attenuates the signature of off-axis companions to the star, like angular differential imaging (ADI). However, the attenuation due to SDI has the particularity to be dependent on the spectral properties of the companions. To date, no study has investigated these effects in the details. Our team is addressing this problematic based on data from a high-contrast imaging survey of 16 stars combining the phase-mask coronagraph, the SDI and the ADI modes of VLT/NaCo. The observing strategy is similar to the strategy which will be employed in SPHERE and GPI. The prime objective of the survey is to search for cold (Teff < 1000-1300 K) giant planets at separations of 5-10 AU orbiting young and nearby stars (<200 Myr, <25 pc). The second objective is the assessment of sensitivity limits in SDI data, taking into account the photometric and astrometric biases induced by this technique. We did not detect any companions in the processed images. As for the estimation of the sensivity limits of SDI-processed images, we show that it requires a different analysis that for ADI-based surveys, as it measures a photometric difference between two spectral bands. In ADI, the detection limits are measured on contrast maps, which once corrected from various attenuations (ADI and/or coronagraph) are then converted into mass limits at 5 sigma according to a given evolutionary model. In SDI, this method is no longer valid, because the determination of the attenuation requires the knowledge of the spectral properties of unseen companions. We will present a method based on the flux predictions of evolutionary models to determine directly the minimal mass of a companion detectable at a given signal-to-noise ratio as a function of the separation. We compare the mass sensivity limits of the ADI processing alone and the combination of SDI and ADI. The gain in mass sensitivity provided by SDI depends critically on the observing conditions, especially on the shape of the point spread function. For the targets where the combination SDI+ADI improves the mass sensitivity limits with respect to ADI alone, the gain is greater in the region 0.5-1.3'' and can reach values of 20-35%.!

19 Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets

1.07!Poster ! ✩✩✩✩✩Student Vanessa Bailey University of Arizona, Steward Observatory, USA 1 Philip Hinz, Andrew Skemer, Denis Defrere, Simone Esposito, Enrico Pinna, Alfio Puglisi, & Timothy Rodigas The Large Binocular Telescope Interferometer and Adaptive Optics System: On-Sky Performance and Results Increasing spatial resolution and contrast capabilities will make possible new discoveries in the arena of direct exoplanet and exozodi detection. In light of this fact, the Large Binocular Telescope Interferometer (LBTI) has been engineered to sit at the combined focus of the Large Binocular Telescope's two 8.4m apertures. Both apertures are equipped with 672-actuator deformable secondary mirrors, the first of the next generation of "extreme" adaptive optics (AO) systems. Fed by these high-contrast AO systems, LBTI's 3-5um channel, LMIRCam, and its 8-13um channel, NOMIC, are now delivering simultaneous diffraction-limited direct and interferometric imaging. The LEECH L' direct imaging survey for giant exoplanets is already underway, with the HOSTS 10um nulling interferometry exozodi survey to begin this summer. We demonstrate that the stability and high Strehl ratio of the AO PSF, combined with the long observation wavelength, enable LMIRCam to achieve exceptional direct imaging performance on stars up to roughly 1Gyr in age. We describe how the precise wavefront control of the AO and phasing systems allow NOMIC to execute deep nulling interferometric observations of dust in the terrestrial zones around nearby stars, as a pathfinder for future terrestrial planet-finding missions. We present an overview of the LBTI + AO instrument suite and detail current on-sky performance.!

1.08!Poster Mariangela Bonavita INAF-OAPD, Italy Ernst De Mooij. Ray Jayawardhana, & Raffaele Gratton Quick-MESS: a fast statistical tool for Exoplanet Imaging Surveys Most of the exoplanets confirmed so far have been identified through indirect detection techniques. Such a large number of discoveries (over 850 confirmed companions and thousands more candidates) allowed for accurate statistical analyses to address questions related to the distribution of the planet properties, such as the mass, orbital period and eccentricity, as well as the relevance of the host star characteristics (mass, metallicity) on the final frequency and distribution of planetary systems.Since both the transit and the radial velocity techniques are biased towards planets in relatively close orbits, orbital separations larger than ~5 AU are currently not well sampled. Direct imaging surveys, which are typically more sensitive to planets at larger orbital separations can fill this gap. However, to predict the expected planet fractions, the distributions derived from the radial velocity and transit surveys need to be extrapolated. Several tools have been developed in the past few years for the statistical analysis of the exoplanet search surveys, mostly using a combination of Monte-Carlo simulations or a Bayesian approach.The main goal of these studies is to assess at what confidence planet distributions obtained from RV surveys can be extrapolated to estimate the planet distributions to the orbital separations where DI is more sensitive.In this talk we present a novel approach to the statistical analysis of Direct Imaging surveys, called Quick- MESS, where the standard Monte Carlo approach is replaced by a grid-based sampling of the orbital parameters. Quick-MESS uses the contrast curves for direct imaging surveys to assess for each target the probability that a planet of a given mass and semi-major axis can be detected. By using a grid-based approach Quick-MESS is typically more than an order of magnitude faster than tools based on Monte-Carlo sampling of the planet distribution. In addition, Quick-MESS is extremely flexible, enabling the study of a large range of parameter space for the mass and semi-major axes distributions without the need of re-simulating the planet population. In this talk we will present the main features of the code, its differences and advantages with respect to the classical Monte- Carlo tools, and some examples of its applications. !

20 Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets

1.09!Poster ! ✩✩✩✩✩Student Timothy Brandt Princeton University, USA Michael W. McElwain, Masayuki Kuzuhara, Joshua Schlieder, John P. Wisniewski, Edwin L. Turner, L. Abe, W. 1 Brandner, J. Carson, S. Egner, M. Feldt, T. Golota, M. Goto, C. A. Grady, O. Guyon, J. Hashimoto, Y. Hayano, M. Hayashi, S. Hayashi, T. Henning, K. W. Hodapp, M. Ishii, M. Iye, M. Janson, R. Kandori, G. R. Knapp, T. Kudo, N. Kusakabe, J. Kwon, T. Matsuo, S. Miyama, J.-I. Morino, A. Moro-Martin, T. Nishimura, T.-S. Pyo, E. Serabyn, H. Suto, R. Suzuki, M. Takami, N. Takato, H. Terada, C. Thalmann, D. Tomono, M. Watanabe, T. Yamada, H. Takami, T. Usuda, & M. Tamura The ACORNS-ADI Data Reduction Pipeline and its Application to Moving Group Targets from the SEEDS High-Contrast Imaging Survey I will present ACORNS-ADI, a new, open-source, parallelized software package to reduce high-contrast imaging data. ACORNS-ADI is written in python and implements several new algorithms, including a method to register saturated images, an adaptive trimmed mean for combining an image sequence that reduces noise by up to ~20%, and a robust and computationally fast method to compute the sensitivity of a high-contrast observation everywhere on the field of view without introducing artificial sources. These new algorithms offer significant speed and sensitivity improvements over our older IDL software. ACORNS-ADI currently works on data from the HiCIAO instrument on the Subaru telescope and NIRI on Gemini North, but can be easily extended to work on data from other instruments. ACORNS-ADI is freely available for download at http://www.github.com/t-brandt/acorns-adi .I will also present results from the moving groups category of the SEEDS direct-imaging survey. These results consist of observations of more than 60 nearby young stars, reduced with ACORNS-ADI. Nearby stars with reliable young ages are exceptionally valuable for direct-imaging surveys. Exoplanets' near-infrared luminosities depend strongly on their mass and age: these worlds cool and fade as they radiate away their initial heat of formation. The SEEDS moving group targets have reliable cluster ages from ~10 to ~200 Myr, and most have X-ray activity measurements and high-resolution spectroscopy from archival data or from our own follow-up program using the 3.5 meter Apache Point telescope. These targets present a large, uniformly reduced sample with reliable ages. We are using this sample as a core component of a large statistical analysis of exoplanet distributions and properties, which is currently underway.

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1.10!Poster Elodie Choquet Space Telescope Science Institute,USA Remi Soummer, Travis Barman, Christine Chen, John Debes, David Golimowski, James B. Hagan, Dean Hines,David Lafrenière,Bruce Macintosh,Christian Marois, Dimitri Mawet, Margaret Moerchen, Mamadou N'Diaye, Marshall Perrin, Laurent Pueyo, Jacqueline Radigan, Abhijith Rajan, & Glenn Schneider, An Archival Legacy Investigation of Circumstellar Environments (ALICE) using HST NICMOS Data The Archival Legacy Investigation of Circumstellar Environments (ALICE) is conducting a comprehensive and consistent reprocessing of HST-NICMOS coronagraphic survey data to search for point sources and disks using advanced PSF subtraction. The KLIP algorithm (Karhunen-Loève Image Projection) was developed for this project, and has proven very effective at processing the hundreds of selected archival images. This project has already been very successful with numerous detections of previously unseen point sources and several debris disks that we are currently following up by multiple avenues. We give an overview of the project including technical aspects (pipeline architecture), and preliminary scientific results with companion candidates, preliminary survey analysis, improved images of known disks, and first scattered light image of several disks (see abstract by Perrin et al., this meeting). ALICE will deliver high-level science products to the community through the MAST archive at STScI, with the goal to define a standard for such high-contrast imaging products that can be applicable to other projects including ground-based (e.g. Gemini Planet Imager), and future space instruments (e.g. JWST). !

21 Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets

1.11! Poster Laird Close University of Arizona USA 1 Jared Males, Kate Follette, Katie Morzinski, & MagAO Team Direct Imaging of Young Planets at H Alpha with SDI and the new MagAO System We report on a new technique to image directly the accretion signatures of young gas planets in transition disks. Young giant planets are thought to have an excess of H alpha emission that can be observed inside a dust cleared inner disk of transitional disks. However, high-contrast imaging in the visible (H alpha is at 0.656 microns) with AO is not possible with current facility AO systems. Yet we have recently demonstrated Visible AO on a large telescope (D=6.5m) for the first time (Close et al. 2013) with the new 585 element Magellan AO system (MagAO) and its VisAO camera. We can obtain deep 25 milliarcsec images at H alpha with MagAO in 0.7" seeding. A unique mode of the VisAO camera (Males at al. 2012) is its SDI mode (Simultaneous Differential Imager) that can image "in and out" of H alpha simultaneously. Enabling accurate PSF/continuum subtraction of the starlight revealing accreting planets. In this manner we can probe transition disks for faint H alpha emission signatures from forming/accreting planets. Here we report the first high-contrast images of transition disks in H alpha. We will note if any forming planets have been detected in our initial survey. !

1.12!Poster Thayne Currie University of Toronto, Canada Olivier Guyon, Frantz Martinache, Christoph Clergeon, Michael McElwain, & Christian Thalmann A New Frontier Frontier in Exoplanet Direct Imaging: First Results and On-Sky Performance of SCExAO We present the first on-sky results for the Subaru Coronagraphic Extreme Adaptive Optics imager (SCExAO), which is on track to be the first extreme-AO system capable of delivering better than 106 near-IR contrast at several diffraction beamwidths. We describe on-sky verification and performance of key Phase 1 SCExAO components: the PIAA coronagraph, the closed-loop coronagraphic low-order wavefront sensor (CLOWFS), and focal plane wavefront control (``speckle nulling”). In particular, despite poor seeing our speckle nulling algorithm blindly calibrates the brightest diffraction features and results in a significant, persistent contrast gain. We describe current testing of the high-order, Pyramid wavefront sensor which will yield > 90% Strehl ratio and, when combined with Phase 1 components, 10^6-10^7 contrast at small angular separations allowing us to image gas giant planets at solar system scales. Finally, we close by describing the suite of near-IR imagers to be coupled with SCExAO to obtain planet spectra and detect them at sub-diffraction limit separations.!

1.13!Poster Jacqueline Faherty Universidad de Chile, Chile Emily Rice, & Kelle Cruz The Brown Dwarf Kinematics Project: Characterizing Giant Exoplanet Analogs Young brown dwarfs and directly-imaged exoplanets have enticingly similar photometric and spectroscopic characteristics, indicating that their cool, low gravity atmospheres should be studied in concert. We have identified, confirmed, and characterized several new young M and L type brown dwarfs and compared them to directly- imaged planetary-mass companions and exoplanets like 2MASS 1207b and HR8799b. Similarities between the peculiar shaped H band and location on near-IR color magnitude diagrams provide important clues about how to extract physical properties of planets from current brown dwarf observations.!

22 Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets

1.14!Poster Scott Gaudi The Ohio State University, USA Jeremy Kasdin, & Wes Traub 1 The Science and Technology of an Exoplanet- and Disk-Exploration Coronagraph on a Potential WFIRST-AFTA-2.4-m Telescope The prospect of a coronagraph on the currently-studied WFIRST-AFTA-2.4-m telescope, which could be launched in the early 2020s, has excited the interest of exoplanet investigators. The possibility of including a coronagraph on this decadal-survey recommended mission was made possible by the gift of the 2.4-m telescopes to NASA, because the telescope size is large enough (a) to resolve and characterize cool giant planets around nearby stars, and (b) to discover warm and cold debris disks analogous to our zodiacal and Kuiper disks, if they are bright. We outline here the science that might be addressed by such a coronagraph, and some technology considerations. We also discuss the returns the other primary exoplanet science component of WFIRST, a microlensing survey of cold exoplanets.

1.15!Poster ! ✩✩✩✩✩Student Janis Hagelberg Geneva Observatory, Switzerland Damien Segransan, Stephane Udry, Guillaume Montagnier, & Jean-Luc Beuzit First results of the direct imaging campaign for stars with radial velocity drifts in the HARPS and CORALIE planet-search surveys Using radial velocity data from our two planet-search surveys, CORALIE and HARPS,spanning over more than a decade, we selected promising targets for direct imaging of substellar companions to solar-type stars. The observations are conducted on VLT/NACOusing the angular differential imaging technique. First results including two promising substellar candidates, will be discussed in the poster. An overview of the pipeline will also be presented.!

1.16!Poster Sasha Hinkley Caltech, USA Adam L. Kraus, Eric E. Mamajek, Laurent Pueyo, Jackie Faherty, Ben R. Oppenheimer, Michael J. Ireland, Lynne Hillenbrand, Emily Rice, Gautam Vasisht, Neil Zimmerman, Douglas Brenner, Charles A. Beichman, Richard Dekany, Jennifer E. Roberts, Ian R. Parry, Lewis C Roberts Jr., Justin R. Crepp, Rick Burruss, J. Kent Wallace, Eric Cady, Chengxing Zhai, Michael Shao Thomas Lockhart, Remi Soummer, Anand Sivaramakrishnan, Aaron Veicht, & Ricky Nilsson A Re-evaluation of Kappa Andromedae B: New Spectroscopy and Imaging from Keck and Palomar I will report some surprising new results on the "Super Jupiter" Kappa Andromedae B, a 12.8 Jupiter mass object orbiting its host star at 55 AU and initially detected using adaptive optics and coronagraphy at Subaru Observatory. The study I will present is based on an international observational effort using both Keck and Palomar Observatories dedicated to the detailed characterization of this companion. I will show the first near-infrared spectrum of Kappa Andromedae B obtained from Project 1640, the new exoplanet imaging platform at Palomar Observatory. Further, we use Keck aperture masking interferometry to study the close vicinity of the host star Kappa Andromedae A, placing constraints on its binary nature. This observational work is complemented by a comprehensive study of the age of the Kappa Andromedae system using Hertzprung-Russell diagram isochrone analysis. Our analysis of the age of this system combined with the Keck and Palomar observations has uncovered some surprising results about the mass of the companion, which I will present. !

23 Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets

1.17!Poster ! ✩✩✩✩✩Student Elsa Huby LESIA - Observatoire de Paris, France 1 Gaspard Duchêne, Franck Marchis, Guy Perrin, & Sylvestre Lacour FIRST - Fibered Imager foR a Single Telescope FIRST is an innovative instrument dedicated to high dynamic range imaging and high angular resolution. Its principle relies on the pupil remapping technique, which is a combination of both techniques of aperture masking and single-mode fiber spatial filtering, allowing the calibration of the telescope optical transfer function. A prototype of FIRST has been set up on the 3-m Shane telescope at Lick Observatory and since the first light in 2010, several observing runs have been conducted for the observation of binary systems. The first achievement has consisted in resolving the Capella binary system at the diffraction limit of the telescope in the visible wavelengths range (600-850nm). The spectral flux ratio between the two components has been measured with a spectral resolution of 300, and the derived effective temperatures are in agreement with previous measurements. These results are promising as for the future developments of instruments based on aperture masking / pupil remapping techniques in the context of exoplanetary systems detection. !

1.18!Poster Matthew Kenworthy Leiden Observatory, The Netherlands Sascha Quanz, Tiffany Meshkat, John Codona, Frans Snik, Michael Meyer, Markus Kasper, & Julien Girard Successes and Challenges of the APP Coronagraph The apodizing phase plate (APP) coronagraph has been used to image the exoplanet beta Pictoris b and the protoplanet candidate around HD 100546, and is currently in use in surveys with NaCo at the VLT. Its success is partially due to its tolerance to tip-tilt pointing errors in current AO systems. Currently the sensitivity of the coronagraph is limited by non-common path errors in the science camera systems and by its chromatic behaviour. We present the next generation of achromatic APP coronagraph designs and address how we will measure and minimise non-common path errors with Focal Plane Wavefront Sensing algorithms. !

1.19!Poster ! ✩✩✩✩✩Student Mihoko Konishi Osaka University, Japan Hiroshi Shibai, Taro Matsuo, Kodai Yamamoto, Jun Sudo, Matthias Samland, Misato Fukagawa, & Takahiro Sumi Estimation of Contaminants for Direct Imaging of Exoplanets: Constraint on the Stellar Distribution Model with both NIR and Deep Imaging Data There are some faint contaminants near the primary star in the direct imaging of exoplanets. Our final purpose is the statistical estimation of the rate of exoplanets out of the detected number of point sources by calculating the fraction of expected contamination due to background and foreground objects. There are no previous studies which constrain the stellar distribution model of our galaxy using both NIR and deep imaging data. In this study, we compared the number of detected stars with the number of the contaminants predicted from our model. We used the observation results of two target areas; the Pleiades open cluster and the GOODS-South field observed with HST (Windhorst et al. 2011). The Pleiades direct imaging data was obtained for the search of exoplanets in the context of the SEEDS project (Strategic Exploration of Exoplanets and Disks with Subaru). As for the contaminants, we focused on late-type main-sequence field stars. We employed the stellar distribution models composed of a thin disk, thick disk and halo to predict the number of contaminants for every sub-spectral type from K2 to T7.As the result, we find that the number of faint stars observed differs from the predicted results employing the parameters of the conventional galactic models. We thus estimate the galactic model parameters in correspondence to the results of the observations. This implies two things. Firstly, we note that based on the results of the Pleiades observations we cannot distinguish between the thin disk and the thick disk. Secondly, we find from the observations of the GOODS-South field, that the number of M-type stars in the halo is smaller than conventionally assumed. In the future, we will constrain the model further with other deep imaging data to allow for better statistical estimation of the occurrence rate of exoplanets. !

24 Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets

1.20!Poster ! Michael Liu University of Hawaii, USA Eric Nielsen, Zahed Wahhaj, Beth Biller, Tom Hayward, Laird Close, Mark Chun, Christ Ftaclas, Douglas Toomey & 1 The Gemini NICI Planet-Finding Campaign Team The Gemini NICI Planet-Finding Campaign We have completed a deep 250-star observing campaign to directly image and characterize young (<~1 Gyr) extrasolar planets using theNear-Infrared Coronagraphic Imager (NICI) on the Gemini-South 8.1-meter telescope. NICI is the first instrument designed from the outset for high-contrast imaging on a large telescope, comprising a high-performance adaptive optics (AO) system with a simultaneous dual-channel coronagraphic imager. In combination with state-of-the-artAO observing and data analysis, the NICI Campaign achieves about 2magnitudes better contrast compared to any previous ground-based or space-based planet-finding efforts. We describe the Campaign's design,on-sky performance, and results, including spectroscopic and astrometric characterization of individual interesting discoveries and the strongest statistical results to date on the companion frequency in order to test current models of gas-giant planet formation at >5-10 AU in semi-major axis. Overall, the NICI Planet-Finding Campaign represents the largest and most sensitive imaging survey completed to date for young brown dwarfs and gas-giant planets around other stars. Finally, based on our results, we provide some perspectives on future large exoplanet imaging campaigns with next-generation instruments.

! 1.21! Poster Bruce Macintosh Lawrence Livermore National Laboratory, USA Bruce Macintosh & The Gemini Planet Imager instrument and science team Integration and laboratory performance of the Gemini Planet Imager The Gemini Planet Imager (GPI) is one of the next-generation dedicate instruments for direct imaging, spectroscopy, and polarimetry of extrasolar planets and circumstellar disks. It combines advanced adaptive optics, coronagraphy, precision wavefront sensing, and a integral field spectrometer / polarimeter. GPI is now completing final integration and end-to-end testing at UC Santa Cruz. GPI will ship to Chile in mid-2013 for first light before the end of the year. I will present the status and measured laboratory performance with simulated aberrations. This testing shows that GPI should be an order of magnitude more sensitive than current facilities.

1.22! Poster Jérome Maire Dunlap Institute for Astronomy and Astrophysics, Canada Jonathan Gagné, David Lafreniére, James R. Graham, René, Doyon High-fidelity photometry and astrometry of high-contrast imaged companions using LOCI processing. Direct imaging and spectroscopy of exoplanets is a key element for understanding planet formation and migration. Such direct detections and characterizations remains technologically challenging, since a very high contrast ratio and small angular separation are involved, and futhermore speckle noise limits the high-contrast imaging performance.We further discuss a speckle subtraction and suppression technique that fully takes advantage of spectral and time-domain information on quasi-static speckles to measure the highest-fidelity photometry as well as accurate astrometry of detected companions.!

25 Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets

1.23! Poster ! ✩✩✩✩✩Student Jared Males Steward Observatory, University of Arizona, USA 1 Katie Morzinski, Laird Close, Derek Kopon, Kate Follette, Simone Esposito, Alfio Puglisi, Armando Riccardi, Enrico Pinna, Marco Xompero, Runa Briguglio, Philip Hinz, Timothy Rodigas, & Ya-Lin Wu High Contrast Imaging of an Exoplanet with the Magellan VisAO Camera The Magellan Adaptive Optics (MagAO) system saw first light in November 2012 at Las Campanas Observatory on the 6.5m Clay telescope. Here we present an introduction to MagAO's visible wavelength diffraction limited imager, VisAO. VisAO delivers Strehl ratios greater than 30% from 0.62 microns (r') through 1 micron, where Strehl is even higher, and achieved resolutions as small as 20 milli-arcseconds. We took advantage of the excellent performance of MagAO/VisAO to conduct high contrast observations of an exoplanet in the optical. With VisAO, we are, for the first time, able to begin characterizing exoplanet atmospheres in the optical from the ground.

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1.24! Poster Christian Marois National Research Council of Canada Carlos Correia, Jean-Pierre Veran, & Thane Currie TLOCI, The Next Evolution in Exoplanet/Disk High-Contrast Imaging Exoplanet/Disk imaging requires high level of stellar flux subtraction. The “angular differential imaging” observing technique and the least square LOCI algorithm have now become the standard in single band imaging. With the development of new high-order high-contrast adaptive optics integral field unit (GPI, SPHERE, P1640, …), the image subtraction least square algorithm needs to be modified to allow the optimal use of polychromatic images, same band/ field rotated images and archive data. A new algorithm, TLOCI (for Template LOCI), is presented to achieve this task by “maximizing a companion signal-to-noise ratio” instead of the original LOCI “minimizing of the noise”. The TLOCI technique uses an input spectrum and template PSFs to optimize the reference image least square coefficients to minimize the flux contamination via self-subtraction (thus maximizing its throughput wavelength per wavelength) of any specific planet or disk in the image, while trying to maximize the noise subtraction. A covariance matrix inversion conditioning is used to perform the optimization. The new algorithm has been developed using a simple data set, but laboratory GPI data are also presented as a proof of concept. I will present the TLOCI algorithm, will show typical planet/disk detections and will discuss the planet spectrum recovery challenges.

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1.25!Poster Dimitri Mawet European Southern Observatory, Chile Julien Milli, Olivier Absil, Pierre Baudoz, Anthony Boccaletti, Gael Chauvin, Christian Delacroix, Julien Girard, Anne- Marie Lagrange, et al. Ultra-deep companion search around Beta Pictoris down to 1.75 AU with the newly commissioned L'-band vector vortex coronagraph on VLT/NACO High contrast imaging has thoroughly combed through the limited parameter space accessible with first-generation ground-based adaptive optics instruments and the HST. Only a few objects were discovered, and many non- detections reported and statistically interpreted. The field is now in need of a technological breakthrough. We aim at opening a new parameter space with first-generation systems such as NACO at the Very Large Telescope, by providing ground-breaking inner working angle (IWA) capabilities in the L' band. This mid-infrared wavelength range is a sweet spot for high contrast coronagraphy since the planets-to-star brightness ratio is favorable, while Strehl ratio is naturally higher. An annular groove phase mask (AGPM) vector vortex coronagraph optimized for the L' band, made out of diamond subwavelength gratings has been manufactured and qualified in the lab. The AGPM enables high contrast imaging at very small IWA (here 0".09), potentially being the key to a new parameter space. Here we present the results of the installation and successful commissioning of an L'-band AGPM on VLT/NACO. During a recent science verification run, we imaged the inner regions of Beta Pictoris down to the previously unexplored projected radius of 1.75 AU with unprecedented point source sensitivity. The disk was also clearly resolved down to its inner truncation (see Milli et al., this conference).The new NACO mode is an opportunity to

26 Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets introduce a more rigorous framework for deriving detection limits at very small angles, which is also relevant for SPHERE and GPI and every high contrast imaging instrument with small IWA ambitions. Indeed, classical tools assuming Gaussian statistics, perfectly valid at large separations, loose significance close to the center simply 1 because the sample size decreases dramatically (fewer resolution elements at a given radius). Moreover, the probability density function (PDF) of speckle noise and associated confidence level for detection depend on radius. ADI was shown to transform speckles-modified Rician PDF into quasi-Gaussian PDF at large separations, but it is expected that this property of ADI does not hold true at small angles. Finally, the flux attenuation induced by ADI, potentially significant at small angles, does not scale linearly with the companion brightness, which makes its calibration more difficult. !

1.26!Poster ! ✩✩✩✩✩Student Kyle Mede The University of Tokyo, Japan Yasuhiro Takahashi, Masa Hayashi, Norio Narita, & Motohide Tamura. Solving For The Orbital Elements Of Binary Systems Using Markov Chain Monte Carlo Simulations Through the search for extrasolar planets, surveys are finding many planets exist in systems with multiple stars. The existence of a companion star to a planet hosting primary further complicates the evolution of the planet's orbit. In order to investigate the possible evolution mechanisms, the orbits of the stellar companions need to be accurately determined first. The commonly used radial velocity technique is only capable of detecting companions at separations under about 20AU. The orbits of these systems are normally determined with a least-squares reduction of the well known radial velocity equations, with an accuracy determined by how well the radial velocity curve is known. Now with the advancement of high-contrast instruments, such as HiCIAO on the Subaru telescope, direct imaging out to about 1000AU is possible. Multiple works by Liu et al. over the past 5 years has shown that Markov Chain Monte Carlo (MCMC) simulations can produce more constrained orbital parameter predictions than the methods of the past. We are in the process of developing a similar MCMC simulator that utilizes both of these observing methods to provide three dimensions of data to compare the models to. This new 3D simulator should be able to more accurately constrain the orbital parameters of binary systems than more simple 2D or 1D versions. Once complete, we hope this simulator may be used to help understand the effects on planetary orbit evolution in multiple star systems.!

1.27!Poster Dino Mesa INAF - Osservatorio Astronomico di Padova, Italy Raffaele Gratton, Riccardo Claudi, Silvano Desidera, Enrico Giro, Alice Zurlo, Anne Costilla, Arthur Vigan, Claire Moutou, Jean-Luc Beuzit, & Kjetil Dohlen Performances test on the SPHERE-IFS Until now, just a few extrasolar planets (~30 out of 860) have been found through the direct imaging method. This number should greatly improve when the next generation of High Contrast Instruments like Gemini Planet Imager (GPI) at Gemini South Telescope or SPHERE at VLT will became operative at the end of this year. In particular, the Integral Field Spectrograph (IFS), one of the SPHERE subsystems, should allow a first characterization of the spectral type of the found extrasolar planets.Here we present the results of the last performance tests that we have done on the IFS instrument at the Institut de Planetologie et d'Astrophysique de Grenoble (IPAG) in condition as similar as possible to the ones that we will find at the telescope. We have found that we should be able to reach contrast down to 5x10^(-7) and make astrometry at sub-mas with the instrument in the actual conditions. A number of critical issues have been identified. The resolution of these problems could allow to further improve the performance of the instrument.!

27 Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets

1.28!Poster ! ✩✩✩✩✩Student Tiffany Meshkat Leiden Observatory, Netherlands 1 Matthew Kenworthy, Sascha Quanz, & Adam Amara, Testing Optimized Principal Component Analysis on Coronagraphic Images of the Fomalhaut System We present the results of a study to optimize the principal component analysis (PCA) algorithm for planet detection, a new algorithm to complement ADI and LOCI for increasing the contrast achievable next to a bright star. We apply PCA to the Kenworthy et al. (2013) Fomalhaut VLT NACO/APP NB4.05 data set. We do not detect any companions, with a model dependent upper mass limit of 10-18 Mjup from 4-10 AU. PCA achieves a better contrast curve than the LOCI algorithm for the Fomalhaut coronagraphic data. I will also discuss several modifications made to the PCA code and which of those proved the most effective at maximizing the signal-to-noise from a planet very close to its parent star.!

1.29!Poster Stanimir Metchev Stony Brook University, United States Matthew Wahl, Rahul Patel, & Eugene Serabyn Debris Disk Science with the Palomar ExAO system: First Results I will present first results from using the PALM-3000 adaptive optics system and imaging camera on the Palomar 5 m telescope to survey the inner reaches of nearby circumstellar debris disks. June 2012 observations of the HD 141569A debris disk obtained with the JPL-built vortex coronagraph resolved the disk to unprecedentedly small (0.3") angular separations, indicating that the previously suggested clearing extends inwards to at least 35 AU. An on-going disk imaging survey will resolve scattered light from asteroid belt-temperature material around the nearest debris disk-host stars.!

1.30!Poster ! ✩✩✩✩✩Student Max Millar-Blanchaer University of Toronto, Canada Sloane Wiktorowicz, Marshall Perrin, James Graham, Sandrine Thomas, Daren Dillon, Jerome Maire, Michael P. Fitzgerald, Naru Sadakuni, Bruce A Macintosh, & Stephen J Goodsell Polarimetry with the Gemini Planet Imager: Instrument characterization and Future Science The Gemini Planet Imager (GPI) is a high contrast coronagraph designed to directly image exoplanets and circumstellar disks. GPI includes a polarimetry mode designed to characterize dust grains and enhance the contrast of scattered, polarized light by a factor of 100. Reflections and birefringence of optics within the optical train induce a polarization signature that needs to be measured a priori and calibrated out during data reduction. Here we report on the results of an extensive laboratory characterization campaign of the polarimetry mode. The linear instrumental polarization has been measured in 4 GPI passbands and found to be between at 3.5 +/- 0.3% at 1.0 micron and 1.1 +/- 0.3% at 2.0 microns. Modulation efficiency has been measured to be 94% at 1.0 micron increasing to 97% at 2.0 microns. Stability has been shown to better than 0.6% over timescales of ~ 3 months and over cool down cycles. The tests show that GPI passes all polarimetry design requirements and will be able to measure circumstellar disk linear polarization to 1% accuracy. Using these calibrations we present simulated observations of debris disks of potential early science targets.

28 Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets

1.31!Poster ! ✩✩✩✩✩Student Caroline Morley UC Santa Cruz, USA Caroline Morley, Mark Marley, Jonathan Fortney, & Roxana Lupu 1 Water Clouds and Imaging of the Coolest Giant Planets A major frontier in the fields of directly imaged planets is finding and characterizing the coolest known objects. For planets with effective temperatures below about 450 K, it has long been known that water clouds will form and shape the infrared spectra of these objects. However, no previous modeling studies have systematically shown the effect that water clouds will have on the spectra of these cold planetary-mass objects. Within 1-2 years, GPI and SPHERE will be able to directly image and characterize planets down to ~300 K, so the time is right to better understand cool atmospheres dominated by water clouds. Cold brown dwarfs will also contain water clouds and they provide a test-bed for our new generation of cloudy atmosphere models. The newly-proposed spectral type Y includes brown dwarfs cooler than about 500 K, many of which will have water clouds. Over a dozen Y dwarfs have now been discovered (e.g. Cushing et al. 2011, Kirkpatrick et al. 2012) and are beginning to be characterized (Leggett et al. 2013, Marsh et al. 2013); followup studies by various groups aim to measure their spectra, monitor them for variability, and measure their parallaxes. The models presented here will allow us to determine the physical properties of the Y dwarfs and allow us to compare the brown dwarf population to directly-imaged planets as they are discovered. Here we present a study of clouds in objects that bridge the gap between brown dwarfs and solar system planets, with effective temperatures from 200 to 500 K. We present results for both planetary- mass objects and for Y dwarfs and compare models to available Y dwarf spectra to test their validity. We make predictions for the spectra, colors, and magnitudes of young giant planets and the Y dwarf population. We also predict the level of variability expected in the near- and mid-infrared. References Cushing, M. C. et al. 2011, ApJ, 743, 50 Kirkpatrick, J. D. et al. 2012, ApJ, 753, 156Leggett, S.K., et al. 2013, ApJ, 763, 130 Marsh, K. A., et al. 2013, ApJ, 762, 119!

1.32!Poster Eric Nielsen IfA/Hawaii, United States Michael Liu, Zahed Wahhaj, Beth Biller, Thomas Hayward, Laird Close, Mark Chun, Christ Ftaclas, Douglas Toomey & The Gemini NICI Planet-Finding Campaign Team. Ages and Planets of Young B and A Stars For direct imaging studies, accurate ages for B and A-type stars are crucial for planning search programs and interpreting the results,both for detections and non-detections. Likewise, ages are needed to trace debris disk evolution as a function of time. B and A stars are exciting targets for direct imaging surveys as they include the planet hosts Beta Pic, HR 8799, and Fomalhaut, while RV results also indicate a higher planet frequency for high- mass stars. We show that the traditional method for determining ages for these stars, which assigns Pleiades-ages to all stars at the bottom of the color-magnitude diagram, produces systematically young ages for A stars, especially at the lowest masses. We present a new Bayesian inference technique to produce more accurate posterior probability distributions for ages of B and A stars that incorporates priors based on the age, mass, and metallicity distribution of the solar neighborhood. By applying this method to the 70 B and A stars in the Gemini NICI Planet-Finding Campaign we set strong upper limits on the fraction of high-mass stars that can host wide- separationgiant planets.! In particular, we find that fewer than 10% of high- mass! stars can host a planet like HR 8799 b, at 95% confidence. Finally, we! discuss how applying our Bayesian technique to the planet host kappa And can provide constraints on the age of the system and the nature of super- Jupiter candidate kappa And b.!

29 Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets

1.33!Poster Matthew Penny The Ohio State University, USA 1 & Scott Gaudi Exploring exoplanetary systems beyond 1AU with WFIRST WFIRST (the Wide Field InfraRed Survey Telescope) will be NASA's next flagship astrophysics mission after JWST. Its primary instrument will be a large-format high-resolution near-infrared imager and slitless spectrometer. A primary goal of WFIRST will be to perform a high-cadence microlensing survey of the Galactic bulge to search for low-mass exoplanets beyond the ice line. This poster highlights some of the expected results of the WFIRST exoplanet survey. For example, at Earth-mass, the survey will probe the abundance of planets from less than 1 AU outwards, including free-floating planets. In its peak sensitivity range of ~2-5 AU, WFIRST will be sensitive to planets with masses lower than Mercury. Overall, WFIRST is expected to detect several thousand bound planets, as well as several thousand free-floating planets.!

1.34!Poster ! ✩✩✩✩✩Student Julien Rameau Institut d'Astrophysique et de Planétologie de Grenoble, CNRS, France Philippe Delorme, Gael Chauvin, Anne-Marie Lagrange, Hubert Klahr, Christoph Mordasini, Julien H. Girard, & Mickael Bonnefoy VLT/NaCo study of wide-orbit giant planets around the head and the tail of the young stellar mass distribution Radial velocity and transit are currently the most productive techniques to detect giant planets (GPs). Since 1995, more than 800 GPs have been detected at short periods (< 10yrs; < 5 AU). This large number of detections enables to study the population as a whole. Several statistical analysis enabled to derive the frequency of giant planets as a function of their mass, their semi-major axis and the host properties (spectral type, multiplicity, metallicity). They confirm that planets are not rare (50 % for telluric planets; 10 % for giant ones) at short periods. The planet-metallicity correlation, the multiplicity, the host-star mass correlation, and the density measurement of planetary interiors suggest a formation by a core-accretion mechanism for GPs. At longer periods (>10yrs; >5 AU), the situation is less clear. To explore this parameter space, direct imaging is the unique viable technique but it is, however, very challenging. The discovery of a few planetary mass companions at wide orbits with a low mass-ratio (q ~ 0.2–0.02) around solar to very low-mass stars suggest a stellar-like formation origin. More recently, the discoveries of giant planets around the young and dusty early-type stars HR 8799, Fomalhaut, and β Pictoris at smaller physical separations (‚⧠110 AU) and higher-mass ratio (q ~ 0.002) strengthen a formation within the circumstellar disk either by core accretion (close to the star) or gravitational instability farther away (> 20 AU). Disentangling between these two processes may be however complicated for individual systems as dynamical interactions (planet-planet scattering or planet-disk tides) may have removed the planets from their birth place. Detailed statistical analysis of the planet properties around a large number of targets are needed to compare the relative efficiency of core accretion and gravitational instability.In this context, I will present the results of two three- year surveys of young and nearby stars to search for wide orbit giant planets. On the one hand, we focus on early- type, massive, and dusty stars, namely β Pictoris analogs. On the other hand, we observe late type and very low mass stars, i.e., M dwarfs. I will first discuss the interest of these two classes of targets. I will also present our observing strategies with VLT/NaCo to improve the detection performances to low mass GPs as close as possible to their host-star. Third, I will show the statistical outputs (occurrence, distribution) as well as individual detections of new planetary mass objects. Using these results, I will compare the observed frequency of giant planets between these two classes of parent stars. I will also discuss the implication on GP formation using predictions of the core- accretion scenario and constraints from gravitational instability for both target samples. I will finally present the expected detection capabilities with forthcoming planet finders such as SPHERE or GPI for both classes of objects, and show how they will help us constraining giant planet formation processes in a much better way.Note: If the first session is dedicated to latest improvements in AO (technical session), then this proposed talk should be placed in the session dedicated to the characterization of exoplanetary systems.

30 Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets

1.35!Poster Graeme Salter University of New South Wales,Australia Chris Tinney, Rob Wittenmyer, James Jenkins, Hugh Jones, & Simon O'Toole 1 Direct Imaging Of Long Period Radial Velocity Targets With NICI We are finally entering an era where radial velocity and direct imaging parameter spaces are starting to overlap. Radial velocity measurements provide us with a minimum mass for an orbiting companion (the mass as a function of the inclination of the system). By following up these long period radial velocity detections with direct imaging we can determine whether a trend seen is due to an orbiting planet at low inclination of an orbiting brown dwarf at high inclination. In the event of a non-detection we are still able to put a limit on the maximum mass of the orbiting body. The Anglo-Australian Planet Search (AAPS) is one of the longest baseline radial velocity planet searches in existence, amongst its targets are many that show long period trends in the data. I will present our direct imaging survey of these objects with our results to date. ADI Observations have been made using NICI (Near Infrared Coronagraphic Imager) on Gemini South and analysed using an in house, LOCI-like, post processing.

1.36!Poster Dmitry Savransky Lawrence Livermore National Laboratory, USA Bruce Macintosh, James Graham, & James McBride. Campaign Scheduling and Analysis for the Gemini Planet Imager The Gemini Planet Image (GPI) is a new, high-contrast, exoplanet-imaging, facility instrument for the Gemini South observatory, which is currently undergoing final testing and is scheduled to begin science observations by 2014. The GPI Exoplanet Srvey has been awarded 890 hours to image and spectrally and polarimetrically characterize young, giant planets from a target list of 600 stars of spectral types A-M located within 100 parsecs of the solar system. As part of the instrument validation and in preparation for the survey, we have developed a framework for simulating GPI observations and generating end-to-end survey simulations. Along with a discussion of the scientific goals of the survey, we present new extensions to this modeling and the latest simulations results. We present the expected survey results for planetary radius distributions consistent with the latest Kepler findings and show the ability of the survey to constrain numerical fits to the planetary mass function over the observed range of orbital separations. We also discuss systematic methods for scheduling the surveys to ensure that the population of discovered planets is useful in constraining formation models and possibly distinguishing between gravitational collapse and core accretion as the primary formation mechanism.!

1.37!Poster Andy Skemer University of Arizona, USA Daniel Apai, Vanessa Bailey, Beth Biller, Mickael Bonnefoy, Wolfgang Brandner, Esther Buenzli, Laird Close, Justin Crepp, Denis Defrere, Silvano Desidera, Josh Eisner, Simone Esposito, Jonathan Fortney, Thomas Henning, Phil Hinz, Karl-Heinz Hofmann, Jarron Leisenring, Jared Males, Rafael Millan-Gabet, Katie Morzinski, Ilaria Pascucci, Jenny Patience, George Rieke, Dieter Schertl, Josh Schlieder, Mike Skrutskie, Kate Su, Gerd Weigelt, & Chick Woodward LEECH: A Large Direct Imaging Survey with the LBT We will present early results from LEECH (LBTI Exozodi Exoplanet Common Hunt), a 100 night direct imaging program that began in February 2013 at the LBT. While most direct imaging planet searches work in the near- infrared (H-band; ~1.6 Œºm), LEECH observes in the mid-infrared (Lʼ; ~3.8 μm) where cool, low-mass planets emit most of their light, and adaptive optics performance is superb.By looking at a sample of relatively old, very nearby stars (0.1-2 Gyr, <30 pc), LEECH will complement young star surveys (GPI, SPHERE, Project 1640, SEEDS) by discovering a sample of directly imaged planets that are intermediate in age between young planet discoveries and field brown dwarfs. This will directly constrain giant-planet evolution, and help to disentangle the effects of youth and gravity on exoplanet atmospheres. In a parallel LBTI exozodi survey, we will search these same stars for exozodiacal dust (tenuous inner debris disks). Combined with RV, Spitzer and Herschel data (which exist for most of our targets), we will create a census of giant planets and debris disks for the nearest stars, correlating the presence of "signpost" debris disks with extrasolar planets.

31 Session 1: High-Contrast AO Imaging and Direct Imaging of Exoplanets

1.38!Poster ! ✩✩✩✩✩Student Kimberly Ward-Duong Arizona State University, USA 1 Jenny Patience, Robert De Rosa, Abhijith Rajan, Philip Hinz, Andrew Skemer, Katie Morzinski, & Laird Close A Direct Imaging Study to Search for and to Characterize Planetary Mass Companions We present results from two parallel programs to search for new substellar companions to nearby, young M-stars and to characterize the atmospheres of known planetary mass and temperature substellar companions. For the M-star survey, we analyzed high angular resolution archival data on systems within 50pc, including a subset with well- determined young ages based on measurements of several age indicators. The results include stellar and substellar companion candidates, which we are pursuing with follow-up second epoch images. The characterization component of the project involves using Large Binocular Telescope LMIRCam and MMT ARIES direct imaging and spectroscopy data to investigate the atmospheres of known young substellar companions with masses overlapping the planetary regime. These companions exhibit unusually red infrared colors in common with the imaged planetary companions to HR 8799. The young ages of these systems (< 400 Myr) make them important analogs to directly imaged planets, and allow us to explore the atmospheric properties of low mass, low surface gravity objects. The LBT measurements with different mid-IR filters are particularly sensitive to the effects of clouds, chemistry, and metallicity, which enable detailed tests of theoretical atmosphere models. By combining MMT infrared spectra with the L-band LBT data, we have comprehensive wavelength coverage of the bulk of the emergent flux from these young substellar objects. The long-term goal of the study is to use the IR to mid-IR spectra and photometry of the targets to define an empirical sequence of young object atmospheres spanning the brown dwarf/planet mass transition. These atmospheric studies represent the most analogous comparison to the atmospheres of young imaged planets, and provide a means to fundamentally test evolutionary models, enhancing our understanding of the overall substellar population.!

1.39!Poster ! ✩✩✩✩✩Student Schuyler Wolff Johns Hopkins University, USA Marshall Perrin, Karl Stapelfeldt, Gaspard Duchene, John Krist, Caer McCabe, Francois Menard, Deborah Padgett, & Christophe Pinte Resolved Scattered Light Images of the Edge-On Protoplanetary Disk ESO Halpha 569 We present detailed models of the edge-on protoplanetary disk ESO HŒ± 569 in the Chamaeleon I star forming region from resolved scattered light images from HST and its complete spectral energy distribution. Data was obtained as part of an HST campaign to catalogue edge-on disks around young stars in nearby star forming regions (PI: Karl Stapelfeldt). We confirm that this object is an optically thick edge-on disk around a young star with an outer radius of 125 AU. Using full radiative transfer models, we probe the distribution of dust grains and overall shape of the disk (inclination, scale height, dust mass, maximum particle size, inner radius, flaring exponent and surface/volume density exponent). The spectral energy distribution can place constraints on the mass and distribution of grain sizes within a disk, while the scattered light images place constraints on the geometry of the disk. Additionally, we present a comparison with previously studied edge-on disks to place this system in the big picture of disk evolution.!

1.40!Poster ! ✩✩✩✩✩Student Alice Zurlo LAM/INAF, FRANCE Arthur Vigan, Dino Mesa, Claire Moutou, Raffaele Gratton, Kjetil Dohlenand, & the SPHERE team. Performances and limitations of the SPHERE sub-instruments IRDIS and IFS! Next year the new instrument SPHERE will begin science operations at the Very Large Telecope (ESO). This instrument will be dedicated to the search for exoplanet through the direct imaging techniques, with the new generation extreme adaptive optics. In this talk, we present the performances of both focal instruments IRDIS (dual- band imager camera) and IFS (integral field spectrograph). All the results have been obtained with tests in laboratory, simulating the observing conditions in Paranal.We tested several configurations using both instruments together and simulating long coronographic exposures on a star, looking for possible instrumental ghosts, checking the performances of the adaptive optics system and reducing data with the consortium pipeline. The contrast one can reach with IRDIS is of the order of 10^-6 at 1 arcsec separation from the central star, while IFS achieves deeper levels at close separations, with a contrast of ~ 5*10^-7 at 0.5 arcsec. In this presentation, we will focus on the performances and limitations of the current instrument in the IRDIS-IFS observing modes, as they are at the end of the integration phase in Grenoble. !

32 Session 2: Transformative Interferometry & Protoplanetary Disk Imaging

2.01!Invited Review Talk Sean Andrews Harvard-Smithsonian Center for Astrophysics, USA Observing the Hallmarks of Evolution and Planet Formation in Circumstellar Disks Some of the fundamental processes involved in the evolution of circumstellar disks and the assembly of planetary systems are just now becoming accessible to astronomical observations. The new promise of observational work in the field of planet formation makes for a very dynamic research scenario, which is certain to be amplified in the coming years as the revolutionary ALMA facility ramps up to full operations. To highlight some of the new directions being explored in these fields, I will describe how we are using high angular resolution measurements at millimeter/ 2 radio wavelengths to study crucial aspects of the formation and early evolution of planetary systems, including: the gas and dust structures of protoplanetary disks, the growth and migration of disk solids, and the interactions between a young planetary system and its natal, gas-rich disk. !

33 Session 2: Transformative Interferometry & Protoplanetary Disk Imaging

2.02!Contributed Talk ! ✩✩✩✩✩Student Nienke van der Marel Leiden Observatory, The Netherlands Ewine van Dishoeck, Simon Bruderer, Til Birnstiel, Paola Pinilla, Cornelis Dullemond, Tim van Kempen, Markus Schmalz, Joanna Brown, Gregory Herczeg, Geoffrey Mathews, & Vincent Geers Triggered planet formation in action Resolved gas and dust images of a transitional disk and its cavity Planet formation and clearing of protoplanetary disks is one of the long standing problems in disk evolution theory. The best test of clearing scenarios is observing systems that are most likely to be actively forming planets: the 2 transitional disks with large inner dust cavities. We present the first results of our ALMA Cycle 0 program using Band 9, imaging the Herbig Ae star Oph IRS 48 in CO 6--5, C17O 6--5 and the submillimeter continuum in the extended configuration. The resulting ~0.2” spatial resolution completely resolves the cavity of this disk in the gas and the dust. The huge leap in sensitivity provided by ALMA at high frequencies allows a large dynamic range of gas masses inside the dust cavity to be tested. The gas cavity of IRS 48 is only half as large as the dust cavity and the gas surface density inside this gas cavity is at least two orders of magnitude lower than the gas in the surrounding ring. On the other hand, the continuum emission reveals an unexpected huge asymmetry and steep edges in the dust distribution along the ring suggestive of dust trapping. We will discuss the implications of the combined gas and dust distribution for planet formation at a very early stage. This is the first transitional disk with spatially resolved gas inside the cavity, demonstrating the superb capabilities of the Band 9 receivers.!

2.03!Contributed Talk ! ✩✩✩✩✩Student Fabien Anthonioz IPAG,France François Menard, Christophe Pinte, Jean-Baptiste Lebouquin, Jean-Philippe Berger, Myriam Benisty, Wing-Fai Thi, & The PIONIER Collaboration The VLTI/PIONIER survey of T Tauri disks of the southern Hemisphere Studying the inner regions of protoplanetary disks (1-10 AU) is of utmost importance to understand the formation of planets and the accretion process feeding the forming central star.Herbig AeBe stars are bright enough and they have been observed previously by interferometers. The data for the fainter T Tauri stars is much more sparse. Also, previous observations of T Tauri stars were generally limited to a single baseline. In this contribution we will present the results of our ongoing survey at the VLTI. We have used the PIONIER combiner that allows the simultaneous use of 4 telescopes at ESO/VLTI, yielding 6 baselines and 3 independent closure phases at once. PIONIER's integrated optics technology makes it a very sensitive instrument and we have observed 22 T Tauri stars to this date, the largest such survey so far for T Tauri stars .Our results clearly show the very significant contribution of an extended component to the interferometric signal. We will show that the extended component is different from source to source and that the data with several baselines offer a way to improve our knowledge of the disk geometry and/or composition. We will present a more detailed case study to show how the extended component can be associated convincingly to scattered light. These results validate an earlier study by Pinte et al. (2008). These results show that the dust inner radii of T Tauri disks now appear to be in better agreement with the expected position of the dust sublimation radius, contrarily to previously claims. We will conclude this contribution by presenting plans for extending the current survey with both wavelength and baseline coverage to further study the disk geometry. !

34 Session 2: Transformative Interferometry & Protoplanetary Disk Imaging

2.04!Contributed Talk Chunhua Qi Harvard-Smithsonian Center for Astrophysics, USA Karin Oberg, & David Wilner Observational Signatures of the CO Snow Line in Protoplanetary Disks The condensation front (snow line) of planet-forming volatiles in protoplanetary disks plays an important role in the process of planet formation. CO is believed to condense out on dust grains in the disk midplane when the temperature is lower than ~20K and its snow line may boost planet formation in the outer disk by providing extra solid masses (Dodson-Robinson et al. 2009) and inducing planet traps (Masset et al. 2006; Hasegawa & Pudritz 2011), and affect the elemental make-up of the forming gas-giants (Oberg et al. 2011). Localizing the CO snow line 2 directly from millimeter CO data is challenging since CO is expected to remain abundant in the warm atmosphere above the disk midplane, also exterior to the CO snow line. Here we present the evidence of the CO snow line in protoplanetary disks through observations of CO isotopologues and other trace species like N2H+.Using the Submillimeter Array observations of multi-transition, multi-isotope, spatially resolved CO line data, we have constrained the location of the CO snow line in the disk of the Herbig Ae star HD 163296 (Qi et al. 2011). The temperature structure of the disk has been constrained by optically thick multiple CO lines and detailed analysis of the optically thinner 13CO emission reveals a significant column density reduction at around 165 AU that cannot be explained by the overall disk column distribution as traced by the dust. This is interpreted as the result of CO freeze-out and the location as the CO snow line.Another approach to constrain the CO snow line location is to identify trace species that are only present where CO has begun to freeze out (Qi et al. 2013). Here we present first results of this new method to chemically image the CO snow line in the disk around the T Tauri star TW Hya, using high spatial and spectral resolution ALMA observations of N2H+, a species present in large abundance only where CO is highly depleted from the gas-phase. We show that the N2H+ emission presents a large ring, with an inner rim radius that matches model predictions of the location of the CO snow line. This chemical imaging approach has a tremendous potential to constrain the location of the CO snow line in large samples of disks and will enhance our understanding of the formation of different planetary systems. References:Dodson-Robinson et al. 2009, Icarus, 200, 672 Hasegawa, Y. et al. 2011, MNRAS, 417, 1236 Masset, F.S., et al. 2006, ApJ, 642, 478 Oberg, K. I., 2011, ApJL, 743, L16Qi, C., et al. 2011, ApJ, 740, 84Qi, C., et al, 2013, ApJ, 765, 34! 2

2.05!Contributed Talk! Karl Stapelfeldt NASA Goddard Space Flight Center, USA Gaspard Duchene, John Krist, Caer-Eve McCabe, Francois Menard, Deborah Padgett, & Marshall Perrin HST Imaging of New Edge-on Circumstellar Disks in Nearby Star-forming Regions Edge-on, optically thick circumstellar disks have been imaged at subarcsecond resolution around about a dozen nearby young stellar objects (YSOs). In these systems the central star is occulted from direct view, bright star image artifacts are absent,and the disk reflected light is clearly seen. Modeling of priorHST images of edge-on YSO disks has yielded constraints on their outer radii, vertical scale heights, masses, and dust properties.Edge-on disks have been systematically undercounted to date:while 10% of young stars should statistically be occulted by their disk, the observed frequency is < 2%. Thus there is a significant potential for discovering and imaging new examples.The Spitzer Space Telescope has provided the first good spectral energy distributions for the previously known edge-on disks, finding a characteristic double-peak morphology and showing the sources to be strongly underluminous at wavelengths < 3 microns. Using these as templates, we have identified a number of new edge- on disk candidates among YSOs cataloged in Spitzer legacy surveys of nearby molecular clouds.We report on the results of our HST Cycle 19 program to image the best Spitzer-selected edge-on disk candidates. Ten are well- resolved with radii ranging from 30-300 AU, eight for the first time and six showing highly collimated jets. Outstanding individual sources include one showing remarkably little dust lane chromaticity(consistent with evolved grains), a highly flattened disk with a small scale height (suggestive of dust settling), and an asymmetric disk with a misaligned jet which likely traces tidal perturbations in a binary system. Follow-up work to obtain ancillary data and perform scattered light modeling of the best targets is now being pursued.The results of this program will guide a new round of searches for these rare but important snapshots of protoplanetary disk evolution.!

35 Session 2: Transformative Interferometry & Protoplanetary Disk Imaging

2.06!Contributed Talk ! ✩✩✩✩✩Student Jonathan Menu Institute of Astronomy, KU Leuven, Belgium Roy van Boekel, Thomas Henning, Myriam Benisty, Claire Chandler, & Christoffel Waelkens TW Hydrae: multi-wavelength interferometry of a transitional disk For over a decade, the structure of the inner "hole" in the transitional disk of TW Hydrae has been a subject of strong debate. A grasp into the proposed models for the inner-disk region includes a gapped disk with a tenuous inner dust population, a disk gap with an additional dust ring inside, or even a self-luminous companion within the central hole. Of particular interest are the different scales for the inner gap inferred from SED modelling and mm- 2 observations (~4 AU) on the one hand, and mid-infrared interferometry (~0.5 AU) on the other hand. An important question is whether this might indicate a spatial separation in dust populations, which is also seen in the outer disk of TW Hya.To probe the innermost region of the protoplanetary disk, observations at the highest possible spatial resolution are required. We present new near- and mid-infrared (VLTI/PIONIER and VLTI/MIDI) and millimeter (EVLA) interferometric data of TW Hya. On the basis of the new and archival data, we investigate the shortcomings of existing models, both on the inner-disk and the outer-disk scale.In a step towards a better understanding of the TW Hya disk structure, we develop a detailed radiative transfer model from optical to mm-wavelengths. To explore the vast parameter space involved in the parametrized disk model, a genetic fitting algorithm is used to iteratively refine model parameters. This process also reveals interesting degeneracies between parameters, even for this extended data set. Models with a homogeneous dust population from sub-micron to mm-sized grains do not reproduce the observations, instead a spatial separation between small and large grains is found. Multi-scale structures reproduce the observations qualitatively, and quantitative constraints on the inner-disk geometry can be made.!

2.07!Contributed Talk ! ✩✩✩✩✩Student Timothy Rodigas Steward Observatory, University of Arizona, USA Phil Hinz, Andy Skemer, Glenn Schneider, John Debes, Thayne Currie, Jarron Leisenring, Josh Eisner, Jared Males, Kate Follette, & Vanessa Bailey High-Contrast LBT AO Images of Debris Disks at 2-4 microns Several massive exoplanets have recently been imaged around massive stars. In some systems, such as Beta Pic, both a planet and the star's debris disk are detected. Lacking planet detections, understanding a debris disk's morphology, dust grain sizes, and composition can indirectly tell us about the properties of any hidden planets. Spatially resolved images of debris disks at 2-4 microns can help provide this information.We are conducting a high-contrast 2-4 micron imaging survey of bright debris disks using the Large Binocular Telescope (LBT). In this talk, I will show new LBT adaptive optics (AO) images of the edge-on debris disks around the F star HD 15115 (Rodigas et al. 2012, ApJ) and the A star HD 32297 (Rodigas et al. 2013, in prep.). The images were acquired using just a single primary mirror of the LBT, with exceptional AO correction (200-400 modes). For HD 15115, we obtained Ks (2.15 microns) and L' (3.8 microns) images of the disk, both new detections at these wavelengths. These high-contrast images reveal for the first time that the disk is bowed, most likely due to viewing geometry and forward-scattering grains. The overall gray disk color reveals that the dust grains are primarily 1-10 microns in size--a surprise given the disk's formerly blue colors from HST at shorter wavelengths. I will also present evidence for a disk gap near 45 AU, possibly due to dynamical sculpting by an (undetected) planet. For HD 32297, we obtained 3 hours of AO images of the disk at L' (detected at this wavelength for the first time). We detect the disk at high S/N from ~ 0.2-1" (20-110 AU) from the star. I will present ongoing dust grain modeling for this system using 1-4 micron spatially-resolved images, including archival HST data, which we use to constrain the typical dust grain composition and size. I will also present limits on planets in the system and compare these results to other debris disks that are known to harbor planets. This program demonstrates the exceptional ability of the LBT AO system, which can provide spatially-resolved information on targets (disks and planets) that were previously undetectable from the ground.!

36 Session 2: Transformative Interferometry & Protoplanetary Disk Imaging

2.08!Poster! Joanna Brown Harvard-Smithsonian Center for Astrophysics, USA SMA imaging of Herbig Ae/Be disks The physical processes driving the evolution of protoplanetary disks are not well understand. Herbig Ae/Be disks trace star formation around 2-10 solar mass stars, intermediate between high and low mass stars, and likely have different dominant evolutionary processes. An evolutionary sequence from flared to self shadowed disks has been proposed based on SEDs. We have observed a sample of 11 Herbig Ae/Be disks with the Submillimeter Array (SMA), including spatially resolving the majority, to determine if the evolutionary markers in the infrared are 2 reflected by changes in the bulk disk material visible in the millimeter. Herbig Ae/Be stars are relatively rare and the sample studied with millimeter interferometers is even smaller. This survey represents a significant expansion in the total sample, and in particular the self-shadowed group II sources.!

2.09!Poster! James Di Francesco National Research Council of Canada, Canada Rita Mann, Doug Johnstone, Jonathan Williams, Sean Andrews, & Luca Ricci ALMA Cycle 0 Observations of Proplyds in Orion Protoplanetary disks, or "proplyds," are the sites where new solar systems are born. While disk studies to date have focused on regions like Taurus and Ophiuchus for their proximity, stars rarely form in such isolated environments. In fact, there is clear evidence that our own Sun formed near a clustered OB association like Orion. To understand how planets form, it is imperative that we study disk properties in regions representative of their origins. For this reason, we have observed 41 proplyds in Orion with ALMA, to study fundamental disk properties in a massive star forming region. Even in just its Cycle 0 "Early Science" phase, ALMA is uniquely capable of imaging dust and gas emission from the Orion proplyds with its combination of high frequency, sensitivity, resolution, and spatial filtering properties. These 345 GHz continuum and line observations provide the first detailed view into how the clustered environment and UV radiation affect disk properties and evolution. Ultimately, these data will allow us to assess the potential to form solar system analogues in massive star forming regions.!

2.10 !Poster Sally Dodson-Robinson University of Texas, USA Mo "Emma" Yu, & Karen Willacy Probing planet nurseries with rare isotopologues of CO The properties of planet-forming midplanes of protostellar disks remain largely unprobed by observations due to the high optical depths of common molecular lines. However, rotational emission lines from rare isotopologues may have optical depth near unity in the vertical direction, so that the lines are strong enough to be detected, yet remain transparent enough to trace the disk midplane. We have computed chemical models of protostellar disks including different C and O isotopes and detailed photochemical reactions. The CO condensation front is in the giant planet- forming region, within 20 AU of the star. We show that the optical depths of low-order rotational lines of C17O are around unity, which suggests that it may be possible to see into the disk midplane using C17O. In lower-mass disks, the slightly more abundant C18O is a possible midplane probe. ALMA observations would provide estimates of the disk midplane temperature if CO ice line were spatially resolved. With our computed C17O/H2 abundance ratio, we would also be able to measure disk surface densities from the fluxes of low-order C17O transitions.!

37 Session 2: Transformative Interferometry & Protoplanetary Disk Imaging

2.11 !Poster Gaspard Duchene University of California, Berkeley, USA Karl Stapelfeldt, Andrea Isella, Marshal Perrin, Francois Menard, Deborah Padgett, & Christophe Pinte Imaging and modeling SSTTau J042021+281349, a new prototypical edge-on protoplanetary disk We present new high-resolution observations and panchromatic modeling of SSTTau J042021+281349, a 350AU- radius edge-on protoplanetary disk located in the Taurus star-forming region. This object is part of a larger Hubble Space Telescope program to image new Spitzer-selected candidate edge-on disks. The unique orientation of edge- 2 on protoplanetary disks enables detailed analyses of their vertical structure as well as of their dust properties. We have gathered high-resolution visible and near-infrared scattered light images of the system with the Hubble Space Telescope and adaptive optics system on the Keck II telescope, as well as high-resolution millimeter thermal emission maps with CARMA. Our analysis aims at reproducing simultaneously all of these datasets, as well as the Spitzer- and Herschel-populated spectral energy distribution of the system, simultaneously constraining the disk geometry and constituent dust properties. Compared to the well-known HH 30 edge-on protoplanetary disk, the SSTTau J042021+281349 system is particularly remarkable because of its spectacular bipolar jet and the extremely high degree of lateral symmetry of the disk. Indeed, this system is arguably a "cleaner" prototype for this category of disks. In addition, the apparent achromaticity of dust opacity from the visible to the near-infrared in the SSTTau J042021+281349 disk suggests that it is in an advanced stage of dust evolution. We build on similar analyses conducted on other edge-on disks to place this object in the overall scheme of disk evolution.!

2.12 !Poster ! ✩✩✩✩✩Student Antonio Garufi ETH Zurich, Switzerland Henning Avenhaus, Sascha Quanz, Hans Martin Schmid, Carsten Dominik, Sebastian Wolf, Esther Buenzli, & Michael Meyer On the structural diversity of circumstellar disks with polarimetric imaging By using Polarimetric Differential Imaging (PDI) with ground-based 8m telescopes and adaptive optics, we can study protoplanetary disks with unprecedented contrast, spatial resolution, and inner working angle. We present VLT/NACO PDI observations in H and Ks band of a number of young, intermediate-mass stars. The images reveal very complex, asymmetric, and diverse structures (bright rings, dust-depleted cavities, spiral arms) that suggest on- going dynamic processes. Particular attention is paid on the inner (about 10 to 50 AU) regions of these disks. ! 2.13 !Poster Jean-François Gonzalez Centre de Recherche Astrophysique de Lyon, France Christophe Pinte, Sarah T. Maddison, & François Ménard Planet Gaps in the Dust Layer of 3D Protoplanetary Disks: Observability with ALMA The Atacama Large Millimeter/submillimeter Array (ALMA) will have the necessary resolution to observe a planetary gap created by a Jupiter-mass planet in a protoplanetary disk. We ran full 3D, two-fluid Smoothed Particle Hydrodynamics (SPH) simulations of a planet embedded in a gas+dust T Tauri disk for different planet masses and grain sizes. The gas+dust dynamics, where aerodynamic drag least to the vertical settling and radial migration of grains, is consistently treated. The resulting dust distributions are passed to the Monte Carlo radiative transfer code MCFOST to construct synthetic images in the ALMA wavebands. We then use the ALMA simulator to produce images that include thermal and phase noise for a range of angular resolutions, wavelengths, and integration times, as well as for different inclinations, declinations and distances. We also produce images which assume that gas and dust are well mixed with a gas-to-dust ratio of 100 to compare with previous ALMA predictions, all made under this hypothesis.Our findings clearly demonstrate the importance of correctly incorporating the dust dynamics. We show that the gap carved by a 1 M_J planet orbiting at 40 AU is visible with a much higher contrast than the well-mixed assumption would predict. In the case of a 5 M_J planet, we clearly see a deficit in dust emission in the inner disk, and point out the risk of interpreting the resulting image as that of a transition disk with an inner hole if observed in unfavorable conditions. Planet signatures are fainter in more distant disks but declination or inclination to the line-of-sight have little effect on ALMA's ability to resolve the gaps. Signposts of planets in disks should therefore be routinely seen by ALMA in nearby star-forming regions. We present optimized observing parameters to detect them.!

38 Session 2: Transformative Interferometry & Protoplanetary Disk Imaging

2.14 !Poster ! ✩✩✩✩✩Student Jacques Kluska IPAG, France Fabien Malbet, Jean-Philippe Berger, Bernard Lazareff, Jean-Baptiste Le Bouquin, Christophe Pinte, Eric Thiébaut, Fabien Baron, Myriam Benisty, Carsten Dominik, Andrea Isella, Attila Juhasz, Stefan Kraus, Régis, Lachaume, François Menard, Rafaël Millan-Gabet, John Monnier, Férreol Soulez, & Wing-Fai Thi First aperture synthesis imaging survey of Herbig AeBe stars with PIONIER on the VLTI The close environment of Herbig stars is being revealed step by step and appears to be quite complex. Many physical phenomena could interplay : the dust sublimation causing a puffed-up inner rim, a dusty halo, a dusty wind 2 or an inner gaseous component. To investigate more deeply these regions, getting images at the first Astronomical Unit scale is crucial. This has become possible with near infrared instruments on the VLTI. We have developed a new imaging method specific to young stellar objects where, in a similar way as for coronography, we suppress numerically the stellar component from the image to reveal the environment using the spectral differences between these two components. We present the result of this method on the first imaging survey of Herbig stars made by PIONIER on the VLTI. The differences between the targets are being discussed.!

2.15 !Poster Sylvestre Lacour Observatoire de Paris, France The gap of transition disk imaged with aperture masking I will present a technical-oriented talk about aperture masking. I will describe the technique, its advantages, and its shortcomings. I will focus my talk on the numerous observations of transition disks (Herbigs as well as T Tauri stars) and I will show why such a technique is critical for the study of these objects in the context of understanding planetary formation. Finally, I will put into context the recent papers on the subject, highlighting the risk of over- interpreting the data in the light of incomplete spatial information.!

2.16 !Poster ! ✩✩✩✩✩Student Katherine Rosenfeld Harvard-Smithsonian Center for Astrophysics, USA Sean Andrews, David Wilner, Joel Kastner, & Melissa McClure The Structure of an Evolved Protoplanetary Disk Observational evidence of circumstellar disk evolution may provide insight into the process of planet formation. We present sensitive, sub-arcsecond resolution Submillimeter Array observations of a nearby protoplanetary disk and identify several signatures of profound evolution. We study the structure of this disk by simultaneously modeling the spectral energy distribution, continuum visibilities, and spectral line emission of CO and its main isotopologues. We suggest that the disk structure we derive is likely the result of dynamical interactions with a low-mass companion, although photoevaporation may also play a secondary role.!

2.17!Poster! Nikoletta Sipos ETH Zurich, Switzerland & Ágnes Kóspál The inner disks of eruptive young stars EX Lupi-type objects (EXors) form a spectacular class of pre-main sequence stars. They show sporadic brightenings of several magnitudes attributed to the episodic increase in the accretion rate of the circumstellar matter onto the young star. It is supposed that during the early evolution of a Sun-like star these eruptive phases represent an important period of building up stellar mass, and outbursts also affect the circumstellar environment. As the inner disk plays a crucial role during the onset of the outburst, we examined the quiescent properties of the circumstellar environment of EXors. We found that in case of three out of eight EXors the SEDs show no or very weak excess at NIR-MIR wavelengths. This might be indicative of inner disk clearing. A detailed modeling of the sources revealed that the inner regions of the circumstellar disks had to go through significant evolution, either dust is removed from the inner disks up to a couple times of the sublimation radius or is very flattened. This result is particularly interesting because it means that 30% of the EXors show a reduced NIR flux and also accretion rates an order of magnitude higher than what is typical in T Tauri stars for certain periods of time.!

39 Session 3: Building Planets in Protoplanetary Disks: Earliest Evidence

3.01!Invited Review Talk Zoë Leinhardt Bristol, UK The Story of Planets: Anchoring Numerics to Reality Building a complete coherent model of planet formation has proven difficult. There are gaps in the observational record, difficult physical processes that we have yet to fully understand, such as planetesimal formation, and an extensive list of observationally determined constraints that the model must fulfil. For example, the diversity of extrasolar planets detected to date is staggering -- from single hot-Jupiters to multiple planet systems with several tightly packed super-Earths. In addition, the characteristics of the host stars are broad from single solar-mass stars to tight binaries and low mass, low metalicity stars. Even more surprising, perhaps, is the frequency of detection and thus, the implied efficiency of the planet formation process. Any theoretical model must not just be able to explain how planets form but must also explain the frequency and diversity of planetary systems. So why is planet formation so prolific? What parameters determine the type of planetary system that will result? How important are the initial parameters of the protoplanetary disk, such as composition, versus stochastic effects, such as 3 gravitational scattering events, that occur during the evolution of the planetary system? Current observations of extrasolar planets provide snapshots in time of the earliest and latest stages of planet formation but do not show the evolution between the two. It is at this point that we must rely on numerical models to evolve proto-planetary disks into planets. But how can we validate the results of our numerical simulations if the middle stages of planet formation are effectively invisible? Collisions are a core component of planet formation. Planetesimals, the building blocks of planets, collide with one another as they grow and evolve into planets or planetary cores and are viscously stirred by larger protoplanets and fully-formed planets. The range of impact parameters encountered during growth from planetesimals to planets span multiple collision outcome regimes: cratering, merging, disruption, and hit-and-run events. Most of these collisions produce significant debris and dust. If we have a good understanding of the production of collisional debris we can use it as an indirect tracer of on- going planetary evolution even if the planets themselves are not directly detectable.

In this talk I will show how numerical simulations of planet formation including realistic collision modelling can be used to predict, and be constrained by, observations.

40 Session 3: Building Planets in Protoplanetary Disks: Earliest Evidence

3.02!Contributed Talk! Aake Nordlund Niels Bohr Institute, Univ. of Copenhagen, Denmark Troels Haugbølle, & Paolo Padoan Zooming in on Proto-Planetary Disks We use the adaptive mesh refinement computer code RAMSES to model the formation of protoplanetary disks in realistic star formation environments, with resolution scaling over 30 powers of two (about 9 powers of ten), covering a range from outer scales of about 50 pc to inner scales of about 0.01 AU. The simulations are done in three steps, with the first step covering 16 powers of two, following individual star formation in a 50 pc GMC model. In the 2nd step, the neighborhoods of stars with a final system mass of about two solar masses are followed during the accretion process, with a smallest mesh size of 2.5 AU, sufficient to follow the development of the large scale structure of their accretion disks. Finally, a selection of these disks are studied over shorter time intervals, with cell sizes ranging down to 0.01 AU, sufficient to resolve the vertical structure of a significant radius fraction of the disks.The purpose of this procedure is to characterize the typical properties of accretion disks around solar mass protostars, with as few free parameters as possible, and to gather a statistical sample of such conditions, to quantify the extent of statistical variation of properties. This is a vast improvement over models where initial and 3 boundary conditions have to be chosen arbitrarily. Here, the initial and boundary conditions follow instead from the statistical properties of the interstellar medium, which are reasonably well established, as per for example the “Larson relations” and the “B-n” relation, which provide typical values for the velocity and magnetic field RMS values on different scales.As a byproduct of this type of modeling, which starts out from a supernova driven interstellar medium, we can follow the transport of short-lived radioactive nuclides (SLRs), from the time of ejection from supernovae and until they become part of the proto-planetary disks. As shown in a recent paper (arXiv: astro- ph/1302.0843) the transport time is on average short enough to be consistent with initial abundance of 26Al in the Solar System derived from cosmochemistry. Of particular interest is to characterize the amount of variation with time of the SLR abundance during the life time of PP-disks surrounding solar mass stars.

3.03!Contributed Talk! Eugene Chiang UC Berkeley, USA & Ji-Ming, Shi Planetesimal Formation On the long road from dust to planets there are planetesimals. I will review theories of planetesimal formation, including (a) the classic scenario of gravitational instability of a dust-rich midplane, (b) the streaming instability, and (c) particle-particle sticking.!

41 Session 3: Building Planets in Protoplanetary Disks: Earliest Evidence

3.04 !Contributed Talk Catherine Espaillat Harvard-Smithsonian Center for Astrophysics, USA A Herschel View of Dust Evolution in Protoplanetary Disks The details of how protoplanetary disks evolve from initially well-mixed distributions of gas and dust to systems composed mostly of rocky planets and gas giants like our own solar system is a fundamental question in astronomy. It is widely accepted that the first step in planet formation is dust grain growth and settling to the disk midplane. Submillimeter wavelength observations offer us unique access to the disk midplane. I will present the first results from a Herschel SPIRE FTS submillimeter survey of ~150 disks in nearby star-forming regions. By modeling Spitzer IRS spectra and Herschel SPIRE FTS spectra, I will show how we can simultaneously measure the size of the smaller dust in the upper layers of the inner disk and the size of larger dust in the disk midplane, which are intricately related to each other via dust grain settling. I will present evidence for significant dust grain growth and settling in young, ~1 Myr old objects as well as evidence for lower gas-to-dust mass ratios than typically assumed for disks. These results provide constraints for theoretical modeling of dust evolution in disks and indicate 3 a path for further study utilizing ALMA.!

3.05!Contributed Talk! Neal Evans University of Texas at Austin, USA & The DIGIT Team The DIGIT Key Program on Herschel: Mineralogy and Gas in Disks I will present results from the Herschel Key Project, Dust, Ice, and Gasin Time (DIGIT) for protoplanetary disks. We have detected the solid-state feature of forsterite at 69 microns in a number of disks. We also have found CO and water in some disks around Herbig Ae/Be stars. In addition,we have studied a number of transitional disks with evidence for gaps cleared by planets.!

3.06!Contributed Talk! Mayra Osorio Instituto de Astrofisica de Andalucia, Spain Guillem Anglada, Jose M. Torrelles, Carlos Carrasco, Luis F. Rodriguez, Paola D'Alessio, Nuria Calvet, Jose F. Gomez, Juan Mayen, & Carolina Duran Substructure and Signs of Planet Formation in the Disk of HD 169142 We present subarcsecond 7 mm continuum observations and detailed modeling of the disk surrounding the nearby Herbig AeBe star HD 169142. Our modeling of the SED and millimeter intensity profiles indicates that the system is in an advanced stage of evolution, in which it is likely that infall and outflow processes have almost halted, and the dust particles have begun to coagulate and settle towards the disk mid-plane to eventually form planetesimals.Our high angular resolution (~0.15") VLA observations reveal a region of enhanced 7 mm emission with internal substructure, with several local emission peaks at radii 20-40 AU. We interpret these features as signs of planetary formation, and we speculate that the observed emission peaks could be tracing possible protoplanetary seeds.!

42 Session 3: Building Planets in Protoplanetary Disks: Earliest Evidence

3.07 !Poster ! ✩✩✩✩✩Student Yukako Aimi Osaka University, Japan Misato Fukagawa, Tomonori Yasuda, Takuya Yamashita, Koji Kawabata, Makoto Uemura, Akira Arai, Mahito Sasada, Takashi Ohsugi, Michitoshi Yoshida, & Hiroshi Shibai Simultaneous Visible and Near-Infrared Variability of Classical T Tauri Stars Many of T Tauri stars (TTs) are surrounded by protoplanetary disks, in which planetary systems are thought to form. Observational study of disk spatial structure can therefore advance our understanding of planet formation processes. Magnitude variation of TTs is one of the useful diagnostics since it can be attributed to the temporal change of disk structure. On the other hand, variability is also expected due to cool spots and/or hot spots on the surface of the star, thus it is important to distinguish the causes of the observed variability. In order to discuss the multiple causes including the connection with disk structure, we examined the amplitude, period, and wavelength dependence of the variability using the simultaneous visible and near-infrared photometry. Our sample consisted of 23 TTs (22 classical T Tauri stars, 1 weak-lined T Tauri star) and 4 Herbig Ae/Be stars. The observations were carried out from November 2007 to February 2008 with TRISPEC mounted on the KANATA telescope of Hiroshima University. The photometric data were obtained with the V, J, Ks filters at the same time. The magnitudes were 3 measured by aperture photometry relative to the comparison stars located in the same field of view (7.0ʻx7.0ʼ). The photometric accuracy was about 0.03 mag in the three bands. We detected the significant variability for all the targets in V, J, and Ks bands. The amplitudes ranged as 0.05 - 3.14 mag in V, 0.09 - 1.58 mag in J, 0.09 - 0.75 mag in Ks, and there can be seen the overall tendency that the stars became redder when they were dimmer in V ( J ). In general, such variability may have been caused by cool or hot spots, occultation by the disk, and variation of thermal radiation at the dust sublimation zone of the disk. Based on the color-magnitude relations obtained between V, J, and Ks bands, it is suggested that the stellar spots are not the only cause of the variability for most of our targets. In addition, 7 stars show the larger total-to-selective extinctions (RV > 3.1) than that in the interstellar medium, implying grain growth in these systems.!

3.08 !Poster Mary Barsony SETI Institute, USA Karl Haisch Jr., & Ken Marsh Disks around Young Brown Dwarfs and Free-Floating Planetary Mass Objects We have refined a novel method of identifying the pre-main-sequence population of nearby star-forming regions,unbiased with respect to the presence or absence of disks, and capable of distinguishing faint background objects from cloud members. We have tested this method against spectroscopically identified cloud members in the central core of the IC 348 cluster with excellent agreement in identifying and characterizing the embedded cloud population, and distinguishing it from background stars. Using this method, we have discovered ~1000 new low mass,brown dwarf, and planetary mass object candidates in the central core of the Rho Oph cloud, of which 80% show the near-infrared excess indicative of the presence of disks. In the central core of the somewhat older IC 348 cluster in Perseus,we have discovered an order of magnitude (47 vs. 5) more brown dwarf and planetary mass object candidates than other workers. We find a much lower disk fraction in IC 348than in the Rho Oph core, consistent with the evolution of inner disks in the more massive, young stellar object (YSO), populations.Our results show that disk dispersal times are similar across the planetary, brown dwarf, and low-mass YSO mass regimes, and provide a large, new set of ALMA targets to investigate the formation of not only planetary, but extrasolar moon-systems.!

43 Session 3: Building Planets in Protoplanetary Disks: Earliest Evidence

3.09!Poster ! ✩✩✩✩✩Student William Best Institute for Astronomy, University of Hawaii, USA & Jonathan Williams Probing the Gas Content of Protoplanetary Disks Protoplanetary disks are natural consequences of star formation. Dust grows and aggregates in the cold, dense interiors of disks, which become the birthplaces for planets. Rocky cores that grow massive enough will accrete gas from the disk and become giant planets, but disks lose most of their mass within a few million years, significantly constraining the timescale for giant planet development. While observed properties of the dust in disks have been successfully modeled, the mass, structure and evolution of the gas in disks remain elusive, due to the invisibility of cold molecular hydrogen. To study the gas, we are observing CO isotopologue (12CO, 13CO, C18O) emission from disks in Taurus, and developing a grid of new parametric models to interpret the observations. The goals are to quantify the effects of freeze-out and dissociation, and ultimately find a robust diagnostic of the gas mass.! 3

3.10 !Poster ! ✩✩✩✩✩Student Hannah Broekhoven-Fiene University of Victoria, Canada & Brenda Matthews A First Look at the Disk Population in the Auriga/California Giant Molecular Cloud The Auriga-California Molecular Cloud (AMC) is a giant molecular cloud in the nearby Gould Belt of star-forming regions. Its membership in the Gould Belt was only recently identified; therefore, it is relatively unstudied compared to other well-known local clouds. Although it has a comparable mass and size to the Orion Molecular Cloud, it is forming far fewer stars. In fact the star formation in the AMC resembles more closely that of low-mass star-forming regions such as Taurus and Perseus. We use observations of the AMC with Spitzer, Herschel and SCUBA-2 to probe the disk population and compare it to the number of protostellar and starless cores in the cloud. We further use these data to constrain the age of the cloud and its star formation history. Comparison of our Spitzer results to the disk and YSO populations in Orion, Taurus and Perseus reveals that there is a high number of Class I and flat sources relative to Class II sources in the AMC, which suggests that the AMC is a relatively unevolved cloud in the Gould Belt. Finally, we describe our plans to search for evidence of grain growth in AMC disks using ALMA and the Jansky VLA (for which some time has been allocated).!

3.11 !Poster ! ✩✩✩✩✩Student Christian Clanton The Ohio State University, USA Ice Lines in Circumbinary Protoplanetary Disks I examine the position of the ice line in circumbinary disks heated by steady mass accretion and stellar irradiation and compare with the critical semi-major axis, interior to which planetary orbits are unstable. There is a critical binary separation, dependent on the binary parameters and disk properties, for which the ice line lies within the critical semi-major axis for a given binary system. For an equal mass binary comprised of 1 M_Sun components, this critical separation is approximately 1.04 AU, and scales weakly with mass accretion rate and Rosseland mean opacity (proportional to [Mdot * kappa_R]^(2/9)). Assuming a steady mass accretion rate of Mdot ~ 10^-8 M_Sun/yr and a Rosseland mean opacity of kappa_R ~ 1 cm^2/g, I show that greater than 80% of all binary systems with total masses M_tot <~ 4.0 M_Sun have ice lines that lie interior to the critical semi-major axis. This suggests that rocky planets should not form in these systems, a prediction which can be tested by looking for planets around binaries with separations larger than the critical separation with Kepler (difficult) and with microlensing. !

44 Session 3: Building Planets in Protoplanetary Disks: Earliest Evidence

3.12!Poster ! ✩✩✩✩✩Student Maria de Juan Ovelar Leiden Observatory, Netherlands Michiel Min, Carsten Domink, Christian Thalmann, Paola Pinilla, Myriam Benisty, & Tiel Birnstiel Imaging diagnostics for transition discs Transition discs are circumstellar discs where, we believe, planet formation takes place. The most characteristic observable features of these objects are gaps of a few tens of AUs in the imaged sub-millimitre emission of the disc, and the lack of the typical 10–20 μm silicate feature in the spectral energy distribution (SED). The commonly accepted interpretation of these observations is that a fraction of the material in the disc is cleared out by a forming planet. Recent observations have, however, revealed discrepancies between the sub-mm and near-infrared polarimetric images of the structure of some of these discs. In this contribution, we aim to explain these discrepancies by analysing imaging observations of such systems with different ground based facilities. We simulate observations of the emitted and scattered light from these discs with VLT/SPHERE-ZIMPOL, Subaru/ HiCIAO, VLT/VISIR and ALMA. We use the 2-D hydrodynamical and dust evolution models of transition discs presented by Pinilla et. al. (2012) to derive the gas and dust distribution in a disc hosting a planet of different masses (Mp = [1,9,15] Mjup) after 3 Myr of evolution. By means of the Monte-Carlo radiative transfer code MCMax, 3 we compute the emitted and scattered flux of the models in different wavelengths. We then simulate observations of these full resolution images taking into account the characteristics of each particular instrument. The presence of the planet generates pressure bumps in the gas distribution of the disc that cause large grains to accumulate while small grains are allowed into inner regions. This spatial differentiation of the grain sizes explains the discrepancies in the observations since different wavelengths and observing techniques trace different parts of the dust size distribution. The characteristics of the dust distribution strongly depend on the mass and position of the planet. Taking advantage of this effect, we show that the combination of visible/near-infrared polarimetric and sub-mm images is an excellent strategy to constrain such properties of the planet.!

3.13 !Poster ! ✩✩✩✩✩Student Julien Faure CEA / Saclay, FRANCE Sébastien Fromang, & Henrik Latter Dynamics of the inner edge of the dead zone in protoplanatary disks The inner boundary betwenn a MRI active and a dead zone has recently been suggested to be a promising site for planet formation: (Dzyurkevich et.al 2010; Lyra and Mac Low 2012.We model the complex interplay between turbulence and temperature to study the edge dynamics and test if those properties hold where more realistic conditions are considered.!

3.14 !Poster ! ✩✩✩✩✩Student Katherine Follette University of Arizona, USA Laird Close, Jared Males, Derek Kopon, Katie Morzinski, Alfio Puglisi, Simone Esposito, Enrico Pinna, Armando Riccardi, Marco Xompero, Runa Briguglio, Ya-Lin Wu, TJ Rodigas, Phil Hinz, Alan Uomoto, & Tyson Hare Directly Probing the Column Density Profile in an Optically Thin Disk: Visible Light Adaptive Optics Imaging of the Orion 218-354 Silhouette Disk We present the first ground-based adaptive optics images of a disk in silhouette. This disk, Orion 218-354, is seen in silhouette against the bright nebular background of Orion and was resolved using the new Magellan Adaptive Secondary AO system and its VisAO camera in Simultaneous Differential Imaging (SDI) mode. This mode allows for simultaneous acquisition of a target on and off of a given spectral line, in this case H-alpha. The continuum (”off” H-alpha) image provides a synchronous PSF, allowing for robust PSF subtraction. PSF subtraction of Orion 218-354 reveals a disk ~1” (400 AU) in radius, with the degree of absorption increasing steadily towards the center of the disk. By virtue of the central star being unsaturated, these data probe inward to a much smaller radius than previous HST images. Our data present a much different picture than previous observers had hypothesized, namely that the disk is optically thin and therefore somewhat evolved. The radial brightness profile provides a direct probe of the extinction at H-alpha and translates simply to a column density, giving a robust estimate of the radial mass profile of the disk. In addition to being among the first high-resolution AO images taken in the optical on a large telescope, these data reveal the power of SDI imaging to reveal disk structure.!

45 Session 3: Building Planets in Protoplanetary Disks: Earliest Evidence

3.15!Poster! Antonio Hales NRAO/ALMA, USA Simon Casassus, M. Hughes, I. De Gregorio-Monsalvo, F. Ménard, B. Dent, D. Wilner, B. Montesinos, Carlos Eiroa, Aina Palau, Jose Maria Torrelles, S. Pérez, D. Mardones, G. Garay, & N. Phillips A gas-rich disk around DX Cha DX Cha (HD 104237) is a southern, optically bright Herbig Ae star with an infrared excess, part of a small stellar group younger than 5 Myr. We used the APEX and ASTE submillimeter telescopes in Chile to search for continuum and gas emission around this system. Using LABOCA in APEX we detect strong continuum emission around HD104237-A and also around HD104237-E. Our ASTE spectrum detects a double-peaked 12CO(3-2) line profile towards the system, typical of a rotating disk. The new sub-mm data is input into MCFOST to produce a disk model that fits the entire SED. The model reproduces well the observed CO line profile, constraining the diskʼs geometry. !

3 3.16 !Poster Marc Joos CEA Saclay, France Patrick Hennebelle, Andrea Ciardi, & Sebastien Fromang Protostellar disks formation The understanding of disks formation and their early stages evolution is crucial to understand planets formation. Prestellar collapse leads to the formation of a protostar as well as the possible build-up of a disk. However, most previous studies, limited to cases where the magnetic field and the rotation axis of the cloud are aligned, have found that even a relatively weak magnetic field may prevent the early formation of massive disks and their fragmentation. Moreover, very few studies investigated the combined effects of magnetic field and turbulence.We perform three-dimensional, adaptive mesh, numerical simulations of magnetically supercritical collapsing dense cores in both non-turbulent and turbulent environment, using the magneto-hydrodynamic code Ramses. At variance with earlier analyses, we show that the transport of angular momentum acts less efficiently in collapsing cores with non-aligned rotation and magnetic field. We also show that the turbulence is responsible for a misalignment between the rotation axis and the magnetic field and can diffuse out the magnetic field of the inner regions efficiently. The magnetic braking is therefore reduced, and massive disks can be built. If the disks are massive enough and the magnetization not too strong, fragmentation can occur.The early formation of massive disks and their fragmentation can take place at moderate magnetic intensities if the rotation axis is tilted or in a turbulent environment, because of misalignment and turbulent diffusion.!

3.17 !Poster Naibi Marinas University of Florida, USA Elizabeth A. Lada, Paula Teixeira, & Charles Lada Lifetimes of Protoplanetary Disks in Very Young Clusters Stars are born deeply embedded in large clouds of dust and gas and are hidden visually from our view. As the material around thestars disperses, these early systems can be characterized using infrared observations thus providing a window into the initial conditions of stellar and circumstellar disk formation and evolution. We will presents results from a study of disk fractions in very young(1 Myr or younger) embedded clusters. We use near-IR photometry and spectroscopy of cluster members from FLAMINGOS to systematically derive spectral types and characterize the stellar population. Stellar parameters are then correlated with excess emission from disks using mid-IR Spitzer IRAC data. We investigate the dependence of early disk fractions on stellar mass and cluster environment, which help us improve theories of planet formation by characterizing the early distribution of disks from which planets form. !

46 Session 3: Building Planets in Protoplanetary Disks: Earliest Evidence

3.18 !Poster Rebecca Martin University of Colorado, Boulder, USA & Stephen Lubow Outbursts on to Young Stars and Planets Understanding angular momentum transport in accretion discs is fundamental to explaining the formation of systems on all scales, from satellite systems, to planetary systems. Turbulence, driven by the magneto-rotational instability (MRI), transports angular momentum outwards allowing accretion on to the central object. However, the MRI may be suppressed by a low ionisation fraction and dead zones can form at the disc midplane. Dead zones are regions with no turbulence that prevent the free flow of material through the disc. Material accumulates in the dead zone and the disc becomes gravo-magneto unstable. Accretion on to the central object occurs in outbursts involving a large fraction of the disc mass. We explain the outbursts as transitions between steady state solutions, one that is fully turbulent and a second that is self-gravitating. Outbursts have been observed in young stellar objects such as FU Orionis systems and we find they should also occur in circumplanetary discs around planets forming from a circumstellar disc. In the late stages of disc evolution, the presence of a dead zone also has important implications for the formation of planets and satellites.! 3

3.19 !Poster Héloïse Meheut CEA Saclay, France Planetesimal formation in large scale vortices Rossby waves are well known in meteorology as a formation mechanism for cyclones, but they have also strong astrophysical impact. The physical mechanisms they involve are especially interesting in differentially rotating disks where they can destabilize the whole disk. I will describe how this Rossby wave instability can help planetesimal formation in protoplanetary disks, by forming large scale vortices and finally concentrating solids in their center. Historically, the Rossby wave instability has mainly been studied in 2D disks with no vertical stratification. I will present full 3D studies of this instability and show how taking into account the vertical stratification of these disks helped solving the puzzle of planetesimals formation. I will then discuss the possibility to detect these vortices in protoplanetary disks.!

3.20 !Poster Farzana Meru ETH Zurich, Switzerland Marina Galvagni, Pascale Garaud, & Christoph Olczak Grain growth in T Tauri and Brown Dwarf discs We perform coagulation and fragmentation simulations to understand the growth of grains in T Tauri and brown dwarf discs. We present a new physically motivated approach to determining the collision velocities of dust particles by combining analytical and numerical techniques. This approach uses a probability distribution function for the collision velocities. Most importantly, the key development is that it separates the deterministic (i.e. directional) and stochastic (i.e. non-directional) velocities. By applying this technique to T Tauri disc conditions, growth to larger sizes is possible compared to previous studies - up to a few tens of metres and metre-sizes at distances of 1AU and 30AU from the central star, respectively. In addition, we also find that growth to large sizes in brown dwarf discs is possible and crucially, we find that if brown dwarf discs are scaled-down versions of T Tauri discs, growth proceeds in similar ways in both discs. This potentially explains the recent observational results whereby growth to millimetre sizes has been detected in brown dwarf discs (e.g. Ricci et al. 2012, 2013). Furthermore, it potentially solves an important problem raised by observations of T Tauri and brown dwarf discs: growing dust aggregates while still maintaining a population of smaller-sized aggregates that are also detected at infrared wavelengths.!

47 Session 3: Building Planets in Protoplanetary Disks: Earliest Evidence

3.21!Poster ! ✩✩✩✩✩Student Henry Ngo California Institute of Technology, USA Marti, Duncan, & Harold Levison LIPAD Simulations of Giant Planet Core Formation Gas giant planet cores must reach a critical mass (about 10 Earth masses) to initiate runaway accretion of their gaseous envelopes from the solar nebula. Observations of stellar disks show that the gas disk lifetime is only 1-10 Myr. The formation of a massive core on such a short timescale is a major challenge for the core accretion model of planet formation. In this work, we seek to determine the dynamical processes that could allow for planetary cores to grow this quickly.We have performed numerical simulations of giant planet core formation from a disk of planetesimals using a new Lagrangian integrator ("LIPAD") by Levison, Duncan, and Thommes, AJ, 2012. Unlike other numerical integrators, LIPAD allows planetesimals to grow or fragment in size due to interactions with each other. Thus, entire planets or planetary cores can grow from a planetesimal disk. Our work is the first time this type of integrator has been used to study planet formation in the outer Solar System. In this first set of simulations, we ignore the (somewhat uncertain) effects of Type I migration associated with gas disk tides.Starting with only a disk 3 of kilometre-sized planetesimals, our simulations show that core accretion can be responsible for generating planetary embryos that are ~10^5 km in size (many Earth masses). We also observe the stages of runaway and oligarchic growth, as predicted by core accretion theory. This is an improvement on previous integrators, where planetary embryos must be seeded instead of arising naturally from a planetesimal disk.Our results show that dust sized particles, created by collisional grinding of planetesimals, can enhance embryo growth rates. However, these dust particles can also become locked in mean motion resonances with the embryos. This drives the entire system towards the central star. We also show that outward embryo migration driven by planetesimal scattering is an important dynamical process to ensure the survival of the embryos. Finally, our work investigates the relationship between gas disk parameters and the resulting embryo sizes.Overall, we show that while our simulations routinely generate embryos with masses of a few Earth masses, it remains a challenge for any core accretion simulation to reach the critical value of 10 Earth masses within the gas disk lifetime. However, these simulations do show that core accretion can be responsible for forming the super-Earth sized planets found in extrasolar systems.

3.22 !Poster Chris Ormel UC Berkeley, USA Jiming Shi, & Andrew Youdin The importance of small particle accretion during planet formation Traditionally, it has been thought that bodies in the 100m to 100km size range -- referred to as planetesimals -- are the building blocks out of which rocky planets and the cores of gas giants form. In this classical picture of planet formation, protoplanets form out of planetesimals by processes like runaway and oligarchic growth, where after they accreted the remainder planetesimals at large gravitational focusing factors. However, I will present several observational and theoretical arguments that challenge the planetesimal-dominated scenario. Instead, I will argue that particles in the millimeter-to-meter size range are the most likely building blocks to form planets.Small particles couple strongly to the gas, which acts to dissipate energy during a gravitational encounter. In turn,a protoplanet gravitationally perturbs the gas flow in its vicinity. Therefore, the particle-planet interaction and accretion behavior is an interplay of aerodynamic and gravito-hydrodynamical effects. I will present recent analytical and numerical results, which solve for the gas flow in the vicinity of (small) protoplanets and discuss the accretion potential as function of particle and planet size. I will show that small particles can be excellent building blocks to form protoplanets quickly, especially in the outer disk, and sketch the conditions that must be fulfilled to render it an efficient process. !

48 Session 3: Building Planets in Protoplanetary Disks: Earliest Evidence

3.23!Poster! Mar Sierra ESA , Spain Catarina Alves, & Bruno Merin A deep Herschel PACS imaging survey of transitional disks The defining characteristic of transitional disks is a reduced opacity in the inner disk, indicating the onset of the disk dissipation phase and thought to represent an intermediate evolutionary state between primordial and debris disks. They constitute the last stage where gas and dust are available to form planets, and therefore their study is of extreme value in understanding planet formation including the formation of our own Solar System.We used PACS photometer to characterise the disk structure and geometry for a sample of transitional disks, to study possible correlations of the disk parameters with their host star and environment. By combining Herschel data with complementary diagnostics (accretion rates, dust masses, multiplicity) we try to determine the likely causes for disk clearing, to ultimately learn about the processes of disk evolution leading to planet formation.! 3

3.24!Poster! Jacob Simon JILA, University of Colorado, USA Xuening Bai, James Stone, Philip Armitage, & Kris Beckwith Turbulence in Protoplanetary Disks We study the nature of turbulence in protoplanetary disks driven by the magnetorotational instability in order to understand the conditions under which planets first begin to form. In particular, we present a series of high resolution gas dynamics simulations that are focused on several radial regions in a model protoplanetary disk. Close to the star where the gas is fully ionized, strong features named "zonal flows" appear in the gas pressure; these features could potentially trap small dust particles for long periods of time, playing a significant role in early planet formation processes. At larger disk radii where the ionization levels are lower, there exist "dead" regions (also important for planet formation) where the MRI is inefficient at producing significant levels of turbulence. By applying representative ionization models to our simulations, we show that beyond a few tens of AU, the geometry and strength of the global magnetic field plays an important role in setting the level of turbulence and the properties of the dead regions. !

3.25!Poster! Susan Terebey Cal State Los Angeles, USA Isella Andrea Isella, & Christopher De Vries Determining protostar masses: L1527 in Taurus Protostar masses have been difficult to determine, in part due to the complex nature of protostar environments. We report on a pilot study to determine the mass of the L1527 protostar using CARMA interferometer data. The velocity channel maps are compared with a model that incorporates 1) LVG radiative transfer, 2) TSC collapse envelope and outflow cavity, and 3) a CARMA interferometer simulation. The models are able to reproduce observed C18O (2-1) channel maps quite well, and are sensitive to the gravity field of the infalling gas. The best-fit protostar mass is 0.24 ± 0.04 Msol. The results confirm the low-mass nature of this class 0 source. !

49 Session 3: Building Planets in Protoplanetary Disks: Earliest Evidence

3.26!Poster Matthijs van der Wiel Institute for Space Imaging Science, University of Lethbridge, Canada David Naylor, Giambattista Aresu, & Göran Olofsson gas signatures of Herbig Ae/Be disks probed with Herschel-SPIRE spectroscopy We present Herschel-SPIRE far-infrared spectroscopy of 14 protoplanetary disk systems around Herbig Ae/Be stars, focussing on the five objects that show detectable spectral line signal in the uninterrupted 447-1545 GHz (671-194 micron) spectra: T Tau, AB Aur, HD100546, HD97048 and HD163296. We specifically highlight the detections of (a) six H2O lines toward T Tau, including both ground-state transitions, and (b) a bright N+ fine- structure emission line toward HD163296.Since our observations are unresolved spatially (beam 17" to 42") as well as spectrally (spectral resolution 1.2 GHz, R=400 to 1300), we rely on models to determine how much of the observed line emission may originate from the protoplanetary disk, rather than from a jet/outflow or a remnant envelope. If any part of the cold water vapour toward T Tau can be assigned to the disk, this would be the third ever protoplanetary disk with cold water gas detected. The N+ emission toward HD163296 is 4 to 5 orders of magnitude brighter than predictions by current disk chemo-physical radiative transfer codes, even when invoking X-ray 3 luminosities that are much higher than appropriate for this star. We believe the majority of the N+ far-infrared emission is likely to stem from the jets of HD163296, which are known to emit X-ray photons.In addition, for each of the five targets, we detect at least 8 of the 10 CO transitions and one or both of the fine-structure lines of atomic carbon. The total of >40 lines in the T Tau spectrum include ladders of HCO+, 13CO and C18O, providing a detailed probe of gas temperatures in the ~50-500 K range. !

3.27!Poster! Chao-Chin Yang Lund Observatory, Sweden & Johansen Anders Large-scale Planetesimal Formation by Streaming Instability It has been a long standing problem in core accretion scenario of planet formation for meter/decimeter-sized solid objects to remain in the gaseous protoplanetary disks due to constant head wind. One of the promising mechanisms to overcome this meter-barrier is the streaming instability, in which viscous interaction between solids and gas can concentrate the solids to the extent that gravitational collapse takes over to produce Ceres-sized planetesimals. Systemic study of this mechanism seems warranted to explore the preferable conditions and the properties of the resulting solid concentration. We conduct the largest-scale simulations of this kind to date, up to 1.6 disk scale heights horizontally and 0.4 disk scale heights vertically. We demonstrate that streaming instability remains robust on large scale and we might have captured enough dynamical range of its nonlinear saturation.!

50 Session 4: Co-evolution of Disks and Planetary Systems

4.01!Invited Review Talk! Richard Alexander University of Leicester, UK Planet formation in evolving protoplanetary discs In this talk I will attempt to summarize our knowledge of planet formation in evolving, dispersing protoplanetary discs. I will first review the physics of disc evolution and dispersal, and show how for most of the disc lifetime evolution is driven by the competition between disc accretion and photoevaporation by high-energy radiation. I will also discuss the observations that we use to test these models, and the major uncertainties that remain. I will then move on to consider planet formation and migration in discs, and discuss how observations of both discs and planets can be used to inform our understanding of these processes. Finally I will discuss the transition disc phenomenon, reviewing the various theoretical models of transitional discs and the prospects for detecting young, forming planets. I will conclude by presenting a schematic picture of how planet-forming discs evolve, and highlighting key areas for future work.!

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51 Session 4: Co-evolution of Disks and Planetary Systems

4.02!Contributed Talk! John Carpenter Caltech, USA Luca Ricci, & Andrea Isella ALMA Observations of Low-mass Stars in the Upper Scorpius OB Association The observed lifetime of circumstellar accretion disks around young stars places empirical constraints on the timescale to form planetary systems. Current observational constraints on the disk lifetime derive nearly exclusively from infrared observations. Because the infrared emission is optically thick, it only traces dust within about 1 AU of the star. Submillimeter continuum and spectral line observations with ALMA are key diagnostics of the outer disk where most of the disk mass resides and most planets form. We will present ALMA observations of 20 low-mass stars in the 5 Myr old Upper Scorpius OB association that are surrounded by disks. Upper Sco is the nearest OB association at this age, and thereby provides an opportunity to obtain sensitive measurements of the disk masses and sizes at a critical evolutionary stage when accretion disks are in the process of dissipating. By comparing the gas and dust properties of disks in Upper Sco with existing observations of 1-2 Myr stars in Taurus and Ophiuchus, we can gain insights on how the disks evolve around low-mass stars.!

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4.03!Contributed Talk! Ruth Murray-Clay Harvard-Smithsonian CfA, USA Clues to Disk Structure from the Distribution of Giant Planets The radial distribution of giant planets orbiting other stars exhibits a sharp increase at approximately 1 AU. Though this distance likely corresponds to the ice line at some times in the histories of some disks, it is well inside the ice line at ~3 AU inferred for the solar system at the time when asteroids formed. If the ice line is not at fault, why does the giant planet population increase at 1 AU? We suggest that the answer to this question may lie in the histories of protoplanetary disks.We propose a model for the structure of protoplanetary disks based on the history of infall from a protostellar cloud and demonstrate that this model can explain trends in the radial distribution of giant planets as a function of planet mass and stellar type.!

52 Session 4: Co-evolution of Disks and Planetary Systems

4.04!Contributed Talk! Yasuhiro Hasegawa ASIAA, Taiwan & Ralph Pudritz Disk inhomogeneities and the origins of planetary system architectures and observational properties The large number of recent high-resolution observations shows that protoplanetary disks have a various kind of “structures” in their properties. For example, SMA observations infer a radial discontinuous structure in the gas- phase CO column density. It is well recognized that this kind of structures, or “inhomogeneities”, in disks are the consequence of the mixture of a number of physical and chemical processes taking place in the disks. Here, we present a very comprehensive study of disk inhomogeneities in which we investigate how the disk inhomogeneities affect planet formation that proceeds in the disks. We demonstrate that disk inhomogeneities give rise to planet traps - specific sites in protoplanetary disks at which rapid type I migration is halted. We show that up to three traps (heat transitions, ice lines and dead zones) can exist in a single disc, and that they move differently as the disc accretion rate decreases with time. The interaction between giant planets growing in such traps may be a crucial ingredient for establishing planetary systems. We also demonstrate that the position of planet traps strongly depends on stellar masses and disc accretion rates. This indicates that host stars establish preferred scales of their planetary systems. We finally discuss the observational properties that can arise from disk inhomogeneities. It is important that such properties may be examined by ALMA observations.! 4

4.05!Contributed Talk! Grant Kennedy University of Cambridge, UK & Mark Wyatt The bright end of the exo-Zodi luminosity function and implications for disk evolution and exo-Earth detectability We present the first characterisation of the 12um warm dust ("exo-Zodi") luminosity function around Sun-like stars, focussing on the dustiest systems, which can be identified by the WISE mission. The dustiest old (>Gyr) systems BD+20 307 and HD 15407A are 1 in 10,000 occurrences, but warm dust is much more common around young (<120Myr) systems, with a 5% occurrence rate. These very different occurrence rates mean that warm dust around young and old stars does not share the same origin if it arises from an in situ process; if all stars only have initially massive asteroid belts they would not be visible at Gyr ages, and if systems like BD+20 307 arise due to random collisions during the main-sequence lifetime, these are too infrequent to explain the high disk occurrence rate for young stars. Using these models, we make predictions for the fraction of stars with exo-Zodi bright enough to cause problems for future exo-Earth imaging attempts. Our prediction should be strongly tested by the Large Binocular Telescope Interferometer, which will provide valuable constraints and input for more detailed evolution models. !

53 Session 4: Co-evolution of Disks and Planetary Systems

4.06!Contributed Talk! Michael Ireland Macquarie University and Australian Astronomical Observatory, Australia & Adam Kraus Orbital Motion and Multi-Wavelength Monitoring of LkCa15 b As part of a deep multi-year non-redundant aperture mask infrared imaging campaign observing transition disks, we present multi-epoch monitoring of the resolved emission seen within the disk gap of LkCa 15. Orbital motion of both the central source and extended lobes as presented in Kraus and Ireland (2012) is clearly detected at the level of 3-4 degrees/year, in both K and L'-bands. Based on these data as well as single-epoch H and M bands epochs, we present two models for the central source - thermal emission from a planet and scattering from an exoplanet Hill-sphere sized cloud of grains with a size distribution tailored to match observations. We also suggest strategies for discriminating between these models based on potential observations with ALMA, with polarized light and with high angular resolution emission line observations including H-alpha.!

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4.07 !Contributed Talk ! Paul Kalas UC Berkeley, USA James Graham, Michael Fitzgerald, & Mark Clampin HST/STIS imaging of Fomalhaut: New main belt structure and confirmation of Fomalhaut b's eccentric orbit High contrast imaging observations with the Hubble Space Telescope show that the nearby star Fomalhaut is surrounded by a dusty debris belt and a candidate planet, Fomalhaut b, located just inside the edge of the belt. Fomalhaut b has unexpected characteristics, such as a relatively blue spectrum, leading to hypotheses that the detected object is a low-mass planet hosting a giant planetary dust ring or cloud seen in reflected light. Here we present new HST/STIS observations made in 2010 and 2012 that authenticate the existence of Fomalhaut b. An MCMC analysis of four epochs of astrometry spread over eight years indicate that the orbit has a~180 AU and e~0.8. In projection, Fomalhaut b crosses the main belt, with 90 per cent of allowed orbital planes lying within 36 degrees of the belt plane. Fomalhaut b's orbit is apsidally aligned with the main belt, and periapse is located approximately 30 AU south of the star. We also show the existence of a 50 AU wide azimuthal dust depletion in the dust belt. These new findings provide a revised picture of Fomalhaut as a dynamically complex system, where the orbit of Fomalhaut b and belt structure signify the presence of additional massive planets orbiting the star.

54 Session 4: Co-evolution of Disks and Planetary Systems

4.08!Poster Anthony Boccaletti LESIA, Paris Observatory, France A.-M. Lagrange, E. Pantin, J.C. Augereau, & S. Quanz The multiple spirals in the disk of HD100546 High contrast imaging is recognized as a mandatory tool to study disks morphology, test the presence of planets or signpost of planets and hence constrain the overall properties of these evolved disks, as a complement to SED fitting and thermal imaging in the mid IR. Among the protoplanetary disks in the solar vicinity for which the spatial resolution is fine enough to probe the distance where planetary formation may occur, the system HD 100546 has recently focused a lot of attention with the announcement by Quanz et al. (2013) of a candidate planet in formation. HD100546 is a young (5-10 Myr) Herbig Be star located at 97 pc and previously imaged with HST. STIS (Grady et al. 2001) and ACS (Ardila et al. 2007) in the visible have revealed a 2-arms spiral pattern located in the 150 - 250 AU region. Here, we report on the first near IR detection of this spiral pattern in the protoplanetary disk of HD 100546 using public data from NICI/Gemini. The data were obtained in the Ks band using a Lyot coronagraph and angular differential imaging. Owing to the gain in angular resolution, we were able to resolve the known spiral pattern as a multiple set of spirals to the south of the star while the northern structure is not detected suggesting a strong anisotropic scattering as already inferred from visible observations. We will present the morphology and photometry of the multiple spiral patterns as well as the limit of detection which bring an additional mass constraints to the candidate forming planet discovered by Quanz et al. (2013). Our measurements are able to draw conclusions on the origin of the spirals (gravitational perturbers or instabilities). 4 4.09 !Poster ! ✩✩✩✩✩Student Claire Davies University of St Andrews, UK & Jane Greaves Angular Mometum Evolution During Star and Planetary System Formation If all angular momentum contained within collapsing cores was conserved during star formation, proto-stars would reach break-up velocities before reaching the main-sequence. Therefore, methods by which proto-stars can lose angular momentum must exist. Stellar angular momentum can be transferred from star to disc via stellar magnetic field lines through a process called magnetic braking. Alternatively, the stellar angular momentum can be lost from the star-disc system completely via stellar or disc winds. The proportion of lost stellar angular momentum that is retained within the circumstellar disc is important to studies of planetary system formation. An increase in disc angular momentum may cause a reduction in the disc surface density, often used as an indicator of a disc's ability to form planets.We introduce the disc-to-star angular momentum ratio as an indication of the angular momentum retained within the disc and present results following it's evolution during the first ~1-5Myr using data available in the literature for nearby regions of star formation, namely the Orion Nebula Cluster, Taurus and IC 348. Our results, sensitive to the outer regions of the discs, show angular momentum ratio values between 10 and 400. We compare this to the solar system where the Jupiter-to-Sun angular momentum ratio is ~17. !

4.10!Poster ! ✩✩✩✩✩Student Ruobing Dong Princeton University, USA Roman Rafikov, Jun Hashimoto, Lee Hartmann, Barbara Whitney, Motohide Tamura, & the SEEDS collaboration A New View of Transitional Disks from the Subaru-Based SEEDS Direct Imaging Survey Transitional disks are protoplanetary disks that have depleted inner regions (i.e. cavities or gaps). Their existence was first suggested by their spectral energy distribution (SED), and has subsequently been confirmed by resolved observations of the cavities at various wavelengths. In the past few years, several ideas on the formation of transitional disks have been proposed, such as photoevaporation, grain growth and evolution, and maybe most excitingly, cavities or gaps opened by planet(s). Since 2010, Subaru has launched a major campaign -- the SEEDS project (Strategic Explorations of Exoplanets and Disks with Subaru) -- to directly image the polarized scattered light from a number of transitional disks at NIR wavelengths. The diffraction limited angular resolution (0.06", or about 8 AU at 140 pc, the typical distance to nearby star forming regions such as Taurus) and the small inner working angle (0.05"-0.1", or about 10 AU at 140 pc) in SEEDS enable us to well resolve the region where planets

55 Session 4: Co-evolution of Disks and Planetary Systems

are likely to form. Using radiative transfer simulations, we study the structure of transitional disks by simultaneously modeling the NIR Subaru images, the SED, and in some cases the sub-mm observations obtained either from literature or from the newly commissioned Atacama Large Millimeter Array (ALMA). We obtain physical disk+cavity structures, and constrain the spatial distribution of the dust grains, particularly inside the cavity and at the cavity edge. Interestingly, we find that in some cases cavities are not present in the scattered light. In such cases we present a new model to simultaneously account for all observations. Decoupling between the sub-um-sized and mm-sized grains inside the cavity, which are responsible for resolved observations at different wavelengths, is required. This may necessitate a mechanism, such as dust filtration, for differentiating the small and big dust in the cavity clearing process. For another group of transitional disks in which Subaru does reveal the cavities at NIR, we focus on whether grains at different sizes have the same spatial distribution or not (i.e. the cavity size and the depletion factor inside the cavity for different dust populations). In addition, spiral-arm-like structures have been identified in Subaru/SEEDS images of several transitional disks (with or without a NIR cavity), which might be signs of ongoing planet formation processes in these systems. With our modeling results, we comment on various transitional disk formation theories, and in particular, their possible planets origin.!

4.11 !Poster ! ✩✩✩✩✩Student Virginie Faramaz IPAG, France H. Beust, J-C Augereau, A. Bonsor, P. Thébault, B. Montesinos, A. Mora, C. Eiroa, J. Marschall, & the DUNES Team Planetary systems dynamics: eccentric patterns in debris disks & planetary migration in binary systems 4 In this poster, I present the highlights of two ongoing projects that deal with the dynamics of planetary systems: one project on eccentric debris disks and their ability to be long-lived, and a second project on planet migration in binary systems. Recent Herschel far-IR observations of the debris disk surrounding the 2-3 Gyr old star Zeta2 Reticuli, obtained part of the DUNES key program, reveal an asymmetric double-lobed circumstellar feature interpreted as a ring like structure seen almost edge-on with an elliptical shape and minimum eccentricity 0.3, extending from 70 to 120 AU. We question in this poster on the origin of the pericenter glow phenomenon in this system, and the ability to maintain the disk asymmetry over Gyrs. Through a modeling method combining analytical predictions, numerical N-body treatment and radiative transfer, we aim at constraining the orbital parameters of hypothetical perturbers that could induce a disk structure compatible with observational constraints. The synthetic images support the hypothesis that the observed double-lobe feature is the signature of an eccentric ring. We show that the structure cannot be produced by the binary companion, and favour the hypothesis of another, planetary mass companion orbiting at several tens of AU from its host star, and on a significantly eccentric orbit. However, recent studies suggest that since Zeta1 Reticuli is a wide binary companion, it could actually have played a part in this, by being responsible for exciting orbital eccentricity of planets around the primary. This is one of the numerous effects one can expect from a binary companion. Another one is the impact it may have on planetary systems evolution, and more specifically on planetary migration. We aim at using and/or modifying N-body codes to investigate the effect of a stellar binary companion on late stages of planetary systems evolution, i.e. on planetesimal driven migration. ! 4.12!Poster Pin-Gao Gu ASIAA, Taiwan & He-Feng Hsieh Asymmetric dust distribution in an eccentric protoplanetary disk as a signpost of a gas giant planet The presence of a cavity in a protoplanetary disk revealed by dust continuum emissions is sometime postulated as a signpost of an embedded gas giant planet. More peculiarly, dust emissions exterior to the cavity are often observed to be asymmetric. We explore the possibility of the asymmetry as a result of the asymmetric distribution of dust in an eccentric protoplanetary disk under the secular gravitational perturbation of an embedded massive gas giant planet. We find that the surface density of the dust well coupled to the disk gas is enhanced around the apocenter of the disk. In addition, the azimuthal distributions of particles of various sizes can deviate significantly due to different coupling to the gas. Overall, the asymmetric structure exhibits a phase correlation between the gas velocity field and dust density distribution. Therefore, our study potentially provides a reality check as to whether an asymmetric disk gap detected at sub-mm and cm wavelengths is a signpost of a massive gas giant planet.!

56 Session 4: Co-evolution of Disks and Planetary Systems

4.13!Poster ! ✩✩✩✩✩Student Taisiya Kopytova MPIA, Germany Vik, Joergens, Aurora Sicilia-Aguilar, Victoria Rodriguez-Ledesma, & Reinhard Mundt Photometry and High-Resolution Spectroscopy of CHXR 20: Origin of the Variability We investigate the nature of variability in a young (~ 2 Myr) pre-main sequence star CHXR 20 (K6, 0.9 M_solar).CHXR 20 is surrounded by a circumstellar disk and shows strong photometric variability in the near- infrared and optical bands.The light curve obtained from the WFI photometry shows an amplitude of 0.6 mag, with a detected period of variability of 6.96 days, which is consistent with previous studies.The radial velocity value measured using the FEROS spectra varies with an amplitude of 3.4 km/s peak-to-peak.Additionally, Ca II IR (8498 Å and 8662 Å) and H_alpha (6563 Å) emission lines are detected in the spectra.Based on line shape analysis, Ca II IR lines are attributed to chromospheric activity and the presence of in-falling material in the star-disk interface.The H$\alpha$ line shows a peculiar shape revealing one emission and two absorption components.This could be formed in the infall, wind and/or moving disk gas clumps, and/or caused by a companion.We test several scenarios for the origin of the variability of CHXR 20.We show that the near-infrared variability could appear due to variable extinction on the line-of-sight, while the optical variability could be caused by hot spots with the temperature 9000--10000 covering 20--30 % of the stellar conference. On the other hand, hot spots usually do not sustain a stable photometric variability as is observed for CHXR 20.More stable cool spots would not produce the amplitude of photometric variations as large as it is for CHXR 20.Neither cool, nor hot spots could cause the variability in the near-infrared.We argue that variable accretion can be excluded from the possible reasons explaining the variability.A companion eclipsing the primary remains one of the plausible scenarios.We estimate the mass m_2 sin i of the potential component as 15 M_J, with semi-major axis of 0.07 AU.Since CHXR 20 is still 4 surrounded by a disk, the scenario of a potential companion makes CHXR 20 a target of particular interest, potentially revealing one of the stages of planetary formation and evolution.Follow-up photometric and spectral observation will allow us to provide additional constraints to the physical model of CHXR 20.

4.14 !Poster Min-Kai Lin CITA, Canada & Ryan Cloutier Gravitational instability of planetary gaps and its effect on orbital migration It has been established that self-gravitating disk-satellite interaction can lead to the formation of a gravitationally unstable gap. This gravitational gap instability may significantly affect the orbital migration of gap-opening perturbers in massive disks. We demonstrate this through customized 2D hydrodynamic self-gravitating disk-planet simulations. We show that the development of global spiral arms associated with the unstable gap leads to strong co-orbital torques. In our disk models, such torques results in net outward migration of the planet, on a timescale of a few ten's of orbital periods. We find the unstable gap outer edge can suddenly trigger outward type III migration, even if there is an initially very little net migration. We find even partial gaps opened by Saturn-mass planets can be unstable, but in practice such planets may undergo rapid inward type III migration before they can open a gap. Thus the instability is only relevant for planet masses sufficiently large to induce gap instability early on (approximately Jovian for our disk models). We suggest that gravitational instability of planet gaps may be relevant to the formation of giant planets on wide orbits through disk fragmentation. !

57 Session 4: Co-evolution of Disks and Planetary Systems

4.15!Poster ! ✩✩✩✩✩Student Carlo Felice Manara ESO-Garching, Germany Leonardo Testi, & Antonella Natta A VLT/X-Shooter study of accretion and photoevaporation in Transitional Disks Transitional Disks (TDs) are considered to be a late evolutionary stage of optically thick massive disks when the inner regions are being evacuated and large holes appear in the IR spectral energy distribution (SED) and are seen in mm-interferometry observations. These holes are thought to be produced by processes of photoevaporation, grain growth, or planet formation. Still, none of these processes alone has been shown to be sufficient to explain all observations. Grain growth models explain the observed IR SEDs of TDs, but are unable to reproduce mm- observations. On the other hand, the possible detection of large mass accretion rates (Macc) in several TDs is at odds with photoevaporative model predictions, which expect a very fast depletion of the gas mass reservoir for accretion in the inner disk. Moreover, planet formation models, which need to include multiple accreting planets to perturb sufficiently the inner disk surface density, still cannot explain completely TDs with large inner hole sizes and high mass accretion rates. Finally, recent ALMA data detect a flow of gas from the outer to the inner disk across the hole, which could be associated with the presence of a planet.In this context, the combination of inner hole size (from mm-observations and IR SED fitting), mass accretion rate and wind properties is a powerful observational diagnostic of disk evolution models, but the current measurements of mass accretion rates for TDs are mostly based on secondary indicators (such as the 10% Halpha width), and very few data on the wind properties for these objects are available. For this reason, we are carrying out a detailed study of the accretion and wind properties of TDs with the VLT/X-Shooter spectrograph. This instrument, thanks to its simultaneous very large wavelength 4 coverage (300-2500 nm), high sensitivity, and medium resolution (R~10000), allow us to derive mass accretion rates from UV-excess fitting and from various emission lines, and to simultaneously detect forbidden lines emission to study the connected wind properties. Combining new and archival X-Shooter observations, we collected a sample of 20 TDs from different nearby star-forming regions. The sample includes objects with both small (<5-10 AU) and large (>15-20 AU) known inner hole size from the literature, and with previous estimated mass accretion rates. We checked their stellar parameters (Teff, Lstar, Av, Mstar) and derived their accretion properties (Lacc, Macc) in a self-consistent way, which makes use of the wide wavelength coverage of X-Shooter, and studied their wind properties by mean of different forbidden emission lines.I will present the results of this study, showing the correlation of the accretion properties with the other parameters, in particular to forbidden line emission and wind properties. I will then discuss the implications of my results in the context of the current proposed models for TDs formation. These results will be used as a benchmark for future theoretical works aiming at a better understanding of the collective properties of TDs.!

4.16!Poster! Erick Nagel Departamento de Astronomía, Universidad de Guanajuato, México Effect of a stellar companion on the modeling of HD 142527 infrared SED The discovery of a companion of the Herbig Ae/Be star HD 142527 motivates the study of the effect that produces on the SED. The main change on the system configuration is the formation of a gap in the disc, following the orbit of the secondary star. Due to this change, a wall forms (outer edge of the gap), which is frontally illuminated by stellar radiation.We present a model for the SED, taking into account all the components: a disc with two gaps (one produced by the stellar companion and the other by potential planets), three walls (two associated with the gaps and the other with dust sublimation), optically thin streams of material in the gaps and the stars.Our two main results are the following: a successful SED model can be constructed when it is included a companion star, and the optically thin material required to fit the spectrum is located in a halo as pointed out in some works,but also inside the gaps. The size of the modeled halo is smaller than the value found in a previous model of the system, being easier to explain the height above the midplane, where the material is located.!

58 Session 4: Co-evolution of Disks and Planetary Systems

4.17!Poster Jenny Patience ASU, USA Joanna Bulger, Herve Bouy, Jean-Louis Monin, Christophe Pinte, Francois Menard, Jin Koda, & C. Darren Dowell Co-evolution of Disks and Planetary Systems Disks are central ingredients for the formation of stars and planets, since they contain the material to fuel the accretion onto the central star, transport and regulate the angular momentum of the system, provide the energy for launching jets, and provide the birth sites of planets. Recent discoveries of trends in the population of exoplanets orbiting low mass stars have suggested intriguing differences compared to the planetary systems around more massive stars and observations of protoplanetary disks around low mass objects are required to investigate possible origins of the distinct populations. Analysis of the Kepler planet candidate statistics shows a steep increase in the occurrence of planets with the smallest radii as host star mass declines. By contrast, the frequency of Hot Jupiters around M-stars is lower than for higher mass stars. In Taurus, ~50% of all members have spectral types later than M3, and the existing submm/mm surveys are fundamentally incomplete and a biased view of the early stages of planet formation. As pre-Main Sequence stars contract onto the Main Sequence, their effective temperatures increase and the M4 limit in a star-forming region corresponds to ~M2 at an age of 1Gyr, comparable to the ~1-few Gyr stars in the Solar Neighborhood. Among the nearest stars, the majority are M-dwarfs, again highlighting the importance of understanding the environments of low mass stars to develop a comprehensive protoplanetary disk population study.With a combination of far-IR, submm and mm measurements from the PACS instrument onboard the Herschel Space Observatory, the SHARCII array at the CSO, and the MAMBO-II array at IRAM, we have observed a sample of 30 low mass stars and brown dwarfs in the Taurus star-forming regions, spanning the M2-M9 spectral types that encompass low mass stars and brown dwarfs. Of the 22 targets observed 4 with Herschel at 70um and 160um, 15 targets observed with SHARCII at 350μm and the 16 targets observed with MAMBO at 1.2mm, 21 are detected in at least one measurement, most for the first time at these wavelengths. The fluxes range from 2.8 mJy at 1.2mm for the brown dwarf CFHT Tau 6 to 2.6 Jy at 350μm for the low mass star IRAS04158. In conjunction with previously reported fluxes at other wavelengths, we have modeled the SEDs of these systems with the radiative transfer code MCFOST to estimate disk properties. For a complete study of disk emission across the stellar/substellar boundary, we have observed all Taurus members with spectral types of M4 and later with the PACS instrument on Herschel, and ALMA observations are approved for the systems with detected disk emission. !

4.18!Poster Elisabetta Rigliaco University of Arizona, USA Ilaria Pascucci, Uma Gorti, Suzan Edwards, & David Hollenbach The Origin of the [OI] Low-velocity Component from Young Stellar Objects The formation time, masses, and location of planets around young stellar objects are strongly impacted by the mechanisms that disperse protoplanetary disks and the timescale over which protoplanetary material is cleared out. Models of protoplanetary disk evolution suggest that viscous evolution and photoevaporation driven by the central star are the main disk dispersal mechanisms. Understanding which of them dominates, requires identifying diagnostics tracing these processes as disks evolve. Several diagnostics have been linked to photoevaporative flows from protoplanetary disks. These are low velocity components (LVC) in emission lines of [O I] 5577√Ö and 6300√Ö, [Ne II] 12.8μm and the CO ro-vibrational band at 4.7μm. In all cases the LVC are slightly blueshifted or centered on the stellar velocity. Here we re-examine the possibility that the [OI] LVC is a tracer of photoevaporative flows using high resolution profiles for ~40 T Tauri stars from a variety of sources (Mayall Echelle, UVES, FEROS and HIRES). We identify several problems with the interpretation of [OI] LVC arising in a X-rays driven photoevaporative flow: (1) The luminosity of the [OI] LVC is correlated with the disk accretion rate, which is in turn correlated with the FUV luminosity. (2) The ratios of [OI]6300/[OI]5577√Ö are much lower than expected for thermal excitation (such as X-ray heating). (3) The profile of the [OI] LVC does not have the same kinematic behavior as the LVC in CO and [Ne II] in stars for which we have all 3 tracers. (4) The FWHM of the [OI] LVC ranges from 20-70 km/s, and are much broader than predicted. These factors, in combination with the average blueshift of -5 km/sec, lead us to conclude that the [OI] LVC traces a region where OH is photodissociated by stellar far-ultraviolet photons, this region is unbound and may belong to a magnetically driven disk wind rather than a photoevaporative flow.!

59 Session 4: Co-evolution of Disks and Planetary Systems

4.19!Poster Raquel Salmeron The Australian National University, Australia Magnetocentrifugal jets and chondrule formation in weakly-ionized protostellar disks Protoplanetary discs are the analogues of the early solar system, and potential sites of current planet formation. Large-scale outflows accelerated from the disc surfaces are a promising mechanism for driving accretion in these systems. These outflows are thought to be driven by magnetic fields and are, in turn, likely to strongly affect the structure, evolution and planet-forming processes in the disc. It is also clear that the microphysical details of the gas and dust in the protostellar environment play a central role in the resulting macroscopic behaviour of the disk, and the accretion process as a whole. On the other hand, a record of the formation process of our own solar system is preserved in primitive meteorites, the ʻbuilding blocksʼ of the solar nebula. Preserved in these samples are a variety of objects that have experienced very high temperatures (~1700-2000 K). However, the preservation of presolar grains in meteorites, geochemical evidence for a poorly-mixed nebula, and astrophysical observations of forming stars suggest a cool protoplanetary disc, where temperatures are too low to produce this thermal processing. ‚Ä®I will examine the launching of outflows from the surfaces of protostellar disks under realistic fluid conditions, particularly pertaining to the field-matter diffusivity and the presence of dust grains mixed with the gas. I will present models that calculate the structure of the disk and its wind and show how the high-temperature meteorite components could have been thermally processed in a radially-extended, magnetocentrifugal wind accelerated from the surfaces of a protostellar disk. Processing at distances of about 1-3 AU can heat the precursors to their melting points and explain their basic properties, while retaining association with the colder 4 material of the Solar Nebula. !

4.20!Poster! Ana Uribe University of Chicago, USA & Arieh Konigl Effects of large scale, strong magnetic fields on planet migration The presence of magnetic fields in protoplanetary disks can have important consequences for planet migration. This has been shown in previous studies, either with a toroidal field, or with a turbulent magnetic field generated by the magneto-rotational instability. In the former case, a uniform toroidal field induces magnetic resonances in the disk which can alter the direction of migration. In the latter case, turbulent fields can lead to stochastic migration for low-mass planets and slowed or reversed migration for intermediate-mass planets. We therefore expect that the presence of large scale poloidal and toroidal magnetic fields can have important consequences for planet migration, especially if one considers the possibility of vertical transport of angular momentum. This is the case in disks that drive a wind through magneto-centrifugal acceleration. We study the migration of low-mass planets in such disks and show how the presence of a large scale magnetic field with multiple components affects the gravitational torques on the planet and the direction of migration.!

4.21!Poster! Alycia Weinberger Department of Terrestrial Magnetism, Carnegie Institute of Washington Alan Boss, Guillem Anglada-Escudé Astrometry in the Service of Planet Formation Studies: Disk Lifetimes in Nearby Star Forming Regions and a Planet Candidate around an Mature Brown Dwarf We present preliminary astrometric results aimed at understanding the lifetime of circumstellar disks and potential for planet formation. We have obtained parallaxes to about a dozen young stars in Chamaeleon I with disks in various evolutionary stages. As an average, this is the first definite distance measurement to Cha I and enables a new set of estimates for the ages of the stars. We are also performing the Carnegie Astrometric Planet Search program searching ~100 nearby late M, L, and T dwarfs for gas giant planets on wide orbits. We have our first candidate around a mature brown dwarf.

60 Session 5: Detailed Studies of Known Exoplanets and Exoplanet Systems

5.01!Invited Review Talk! Jonathan Fortney University of California, Santa Cruz, USA Highlights of Exoplanet Characterization In this talk I review exciting developments in the characterization of individual benchmark planets and planetary systems. Advances to be discussed include: Directly imaged planets with spectroscopy, including HR 8799. Transiting hot Jupiters such as HD 189733b with multi-color thermal emission phase curves. Systems of multiple low-mass low-density planets such at Kepler-11, where mass-loss processes sculpt and alter the nature of the planets. Close-in planets with HST spectroscopy, including the low-mass planet GJ 1214b. I will also highlight likely future advances.!

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61 Session 5: Detailed Studies of Known Exoplanets and Exoplanet Systems

5.02!Contributed Talk! Chris Tinney University of NSW / Australian Centre for Astrobiology, Australia A decade and a half of Anglo-Australian Planet Searching After 15 years of operation the AAPS has revealed a multitude of planetary systems, and its successes have pointed the way to a new generation of southern searches for habitable planets. I'll review our work on the frequency of Jupiter analogs, planet searches around M-dwarfs, transit search & R-M FOLLOW-up and plans to exploit our CYCLOPS fibre-feeds on a next generation spectrograph.!

5.03!Contributed Talk ! ✩✩✩✩✩Student Samantha Lawler University of British Columbia, Canada Brett Gladman, JJ Kavelaars, & Jean-Marc Petit The Debiased Kuiper Belt: Our Solar System as a Debris Disk The dust measured in debris disks traces the position of planetesimal belts. In our Solar System, we are also able to measure the largest planetesimals directly and can extrapolate down to make an estimate of the dust. The zodiacal dust from the asteroid belt is better constrained than the only rudimentary measurements of Kuiper belt dust. Dust models will thus be based on the current orbital distribution of the larger bodies which provide the collisional source. The orbital distribution of many Kuiper belt objects is strongly affected by dynamical interactions with Neptune, and the structure cannot be understood without taking this into account.We present the debiased Kuiper belt as measured by the Canada-France Ecliptic Plane Survey. This model includes the absolute populations for objects with diameters > 100 km, measured orbital distributions, and size distributions of the components of the Kuiper belt: the Classical belt (hot, stirred, and kernel components), the Scattering Disk, the 5 Detached Objects, and the resonant objects (1:1, 5:4, 4:3, 3:2 including Kozai subcomponent, 5:3, 7:4, 2:1, 7:3, 5:2, 3:1, and 5:1).Because a large fraction of known debris disks are consistent with dust at Kuiper belt distances from the host stars, the CFEPS Kuiper belt model provides an excellent starting point for a debris disk model, as the dynamical interactions with planets interior to the disk are well-understood and can be precisely modelled using orbital integrations.!

5.04 !Contributed Talk ! ✩✩✩✩✩Student Raphaëlle Haywood University of St Andrews, UK A. C. Cameron, D. Queloz, S.C.C. Barros, M. Deleuil, R. Fares, M. Gillon, A. Hatzes, A.F. Lanza, C. Lovis, C. Moutou, F. Pepe, D. Pollacco, A. Santerne, D. Segransan, & Y. Unruh Planets and Stellar Activity: Hide and Seek in the CoRoT-7 system Since the discovery of the transiting Super-Earth CoRoT-7b, several investigations have been made of the number and precise masses of planets present in the system, but they all yield different results, owing to the star's high level of activity.Radial velocity variations induced by stellar activity therefore need to be modelled and removed to allow a reliable detection of all planets in the system. We re-observed CoRoT-7 in January 2012 with both HARPS and the CoRoT satellite, so that we now have the benefit of simultaneous radial velocity and photometric data. We fitted the off-transit variations in the CoRoT lightcurve using a harmonic decomposition similar to that implemented in Queloz et al. (2009). This fit was then used to model the stellar radial velocity contribution, according to the methods described by Aigrain et al. (2011) and Lanza et al. (2010). This model was incorporated into a Monte Carlo Markov Chain in order to make a precise determination of the orbits of CoRoT-7b and CoRoT-7c. We also assess the evidence for the presence of one or two additional planetary companions.!

62 Session 5: Detailed Studies of Known Exoplanets and Exoplanet Systems

5.05!Contributed Talk! Mickaël Bonnefoy MPIA, Germany Anthony Boccaletti, Anne-Marie Lagrange, France Allard, Christoph Mordasini, Hervé Beust, Gaël Chauvin, J.H.V. Girard, Derek Homeier, Daniel Apai, Sylvestre Lacour, Daniel Rouan, & Hubert Klahr Properties of the young gas giant planet Beta Pictoris b In 2009, we imaged a gas giant planet orbiting at ~8 AU within the disk of the ~12 Myr old star Beta Pictoris. Beta Pictoris b offers the rare opportunity to study the physical and atmospheric properties of an exoplanet possibly formed by core-accretion. We obtained new photometric data on the planet at J (1.265 µm), H (1.66 µm), and Mʼ (4.78 µm) bands between 2011 and 2012 with NaCo at VLT. These new data enable to built the 1-5 µm spectral- energy distribution (SED) of the planet for the first time. I will detail how we used these new data to derive a spectral type estimate, the photometry, the atmospheric properties (dust content, Teff, log g) and the mass of Beta Pictoris b. I will also discuss how our current knowledge of Beta Pictoris b's properties can help to sketch the formation cond of the object (accretion steps, formation scenario,…).!

5.06!Contributed Talk! Leslie Rogers California Institute of Technology, USA Characterizing the Demographics of Exoplanet Bulk Compositions The Kepler Space Telescope has discovered thousands of sub-Saturn-sized transiting planet candidates. To determine the planet mass, the gravitational influence of the planet candidate must be observed, either through radial velocities (RVs) or transit timing variations (TTVs). Constraints on the planet interior structure are possible for the valuable subset of exoplanets with measurements for both the planet mass and the planet radius. The resulting planet average densities can be used for both a compositional interpretation of individual planets and a statistical 5 interpretation of the ensemble properties. Using planet interior structure models, we constrain the bulk compositions of the more than 50 known sub-Saturn-sized transiting planets with measured masses. Our model considers fully differentiated planets comprised of up to four layers: an iron core, a silicate mantle, a water mantle, and a gas envelope. We calculate the planet interior structure by integrating the coupled differential equations describing an evolving self-gravitating body, employing modern equations of state for the iron, silicates, water, and gas. For any individual planet, a wide range of compositions is consistent with the measured mass and radius. We consider the planets as an ensemble, and discuss how thermal evolution, mass loss, and observational biases sculpt the observed planet mass-radius-insolation distribution. Understanding these effects is crucial for constraining the demographics of small planet bulk compositions and for extracting signatures of the planet formation process from the accumulating census of transiting planets with dynamical confirmation.!

5.07!Contributed Talk! Katie Morzinski University of Arizona/Steward Observatory, USA Laird Close, Jared Males, Andy Skemer, Phil Hinz, Vanessa Bailey, T.J. Rodigas, Kate Follette, Derek Kopon, Ya- Lin Wu, Simone Esposito, Alfio Puglisi, Armando Riccardi, Enrico Pinna, Marco Xompero, & Runa Briguglio High-Contrast Imaging of an Exoplanet with Clio, the MagAO Infrared Camera The 6.5m Magellan Clay telescope's adaptive secondary AO system, MagAO, successfully completed its first commissioning run in Fall 2012, and its second commissioning run in Spring 2013. With a high actuator density and a sensitive pyramid WFS, MagAO achieves ~100 nm rms WFE on bright guide stars in good (0.5" V band seeing conditions) at Las Companas Observatory in Chile. MagAO's infrared camera, Clio, has a comprehensive suite of narrow and broad band filters that allow direct imaging of faint companions from 1-5 um. I will present first- light results from Clio, including images of a young nearby exoplanet in 5 infrared wavelengths.!

63 Session 5: Detailed Studies of Known Exoplanets and Exoplanet Systems

5.08!Contributed Talk! Valerio Nascimbeni Universita' di Padova, Italy Giampaolo Piotto, Isabella Pagano, Antonino Lanza, Gaetano Scandariato, Luigi Bedin, & Luca Borsato Unveiling an exoplanetary Neptunian atmosphere through multiband transit photometry The "effective" radius of a planet is a function of wavelength due to scattering and/or absorption processes, and we can exploit simultaneous multiband transit photometry to probe the atmospheric scale height and composition. We present new photometric data of the recently discovered "hot Uranus" GJ3470b, gathered with the LBC camera at LBT. Light curves of unprecedented accuracy (0.0011 mag in U and 0.00026 mag in a narrow band centered at 972 nm) allowed us to measure a larger planetary radius at shorter wavelengths, which we interpret as a signature of Rayleigh scattering by a large scale height He/H-dominated atmosphere. Further follow-up observations to confirm this result and probe the presence of specific atomic and molecular species is ongoing.!

5 5.09 !Contributed Talk ! ✩✩✩✩✩Student Joe Llama University of St Andrews, UK Moira Jardine, Aline Vidotto, Christiane Helling, & Kenny Wood The Shocking Variability of Exoplanet Transits Asymmetries in exoplanet transits are proving to be a useful tool for furthering our understanding of magnetic activity on both stars and planets outside our Solar System. Near-UV observations of the WASP-12 system have revealed asymmetries in the timing of the transit when compared with the optical light curve. A number of possible explanations have been suggested for this variation, including the presence of a magnetospheric bow shock arising from the interaction of the planet's magnetic field with the stellar wind from it's host star. Such observations provide the first method for directly detecting the presence of a magnetic field on exoplanets. The shape and size of such asymmetries is highly dependent on the structure of the host stars magnetic field at the time of observation. This implies we may observe highly varying near-UV transit light curves for the same system. These variations can then be used to learn about the geometry of the host star's magnetic field.For some systems, such as HD 189733, we have maps of the surface magnetic field of the star at various epochs. In this talk I will show how incorporating these maps into a stellar wind model, I can model the formation of a bow shock around the planet and hence demonstrate the variability of the near-UV transits.!

64 Session 5: Detailed Studies of Known Exoplanets and Exoplanet Systems

5.10 !Contributed Talk ! ✩✩✩✩✩Student Korey Haynes GMU/NASA GSFC, USA Evan Sinukoff, Nikku Madhusudhan, Adam Burrows, Drake Deming, & Avi Mandell Exoplanet Transit Spectroscopy of Hot Jupiters Using HST/WFC3 The Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST) provides the potential for spectroscopic characterization of molecular features in exoplanet atmospheres, a capability that has not existed in space since the demise of NICMOS on HST and the IRS on Spitzer. WFC3 is an optical/NIR camera with the capability for slitless grism spectroscopy, with wavelength coverage in the the IR spanning between 0.8 and 1.7 microns. Studies of exoplanets have focused on the G141 grism, the long-wavelength dispersion element on the infrared channel that covers the wavelength range 1.1 to 1.7 microns at a maximum resolving power of 130 (Dressel 2012). This region spans both the major bands of water between 1.3 and 1.5 microns as well as another water band at 1.15 microns, and bands of several other simple molecular species. Observations measuring flux within NIR water bands are impossible from the ground due to the extinction and variability caused by water vapor in the Earthʼs atmosphere; WFC3 therefore represents the only current platform for measuring absorption and/or emission from water in exoplanet atmospheres.We present analysis of transit spectroscopy of a number of extrasolar planets observed as part of a Large Program during the HST Cycle 18, including WASP-12 b, WASP-17 b, and WASP-19 b. WASP-12 b and WASP-19 b are two of the hottest exoplanets discovered to date, while WASP-17 b has a much lower equilibrium temperature but has one of the largest atmospheric radii of known transiting planets; measurement of molecular absorption in the atmospheres of these planets offers the chance to explore several outstanding questions regarding the atmospheric structure and composition of these highly irradiated, Jupiter-mass objects. We analyze the data for a single primary transit for each planet using a strategy similar in certain aspects to the techniques used by Berta et al. (2012), but we extend their methodology to allow us to correct for channel- or wavelength-dependent instrumental effects by utilizing the band-integrated time series and measurements of the drift of the spectrum on the detector over time. We achieve almost photon-limited results for individual spectral bins, but the uncertainties in the transit depth for each bin and especially for the band-integrated data are greatly hampered by the uneven sampling of the light curve imposed by the orbital phasing of HSTʼs observations. Our final transit spectra are consistent with the presence of a broad absorption feature at 1.4 microns most likely due to 5 water, but the amplitude of the absorption is less than expected based on previous observations with Spitzer, possibly due to hazes absorbing in the NIR. However, the degeneracy of models with different compositions and temperature structures combined with the low amplitude of any features in the data preclude our ability to place unambiguous constraints on the atmospheric composition without a comprehensive multi-wavelength analysis.

65 Session 5: Detailed Studies of Known Exoplanets and Exoplanet Systems

5.11 !Poster France Allard Centre de Recherche Astrophysique de Lyon, France Derek Homeier, & Bernd Freytag Imaged Planet Model Atmospheres Over recent years we have developed a cloud model to model very low mass stars and brown dwarfs. The models reproduce the stellar-substellar M-L-T transition. In this paper, we present the results of these PHOENIX static 1D BT-Settl models when applied to Extrasolar Giant Planets observed by imagery. Some planets have shown extreme red colors compared to those of brown dwarfs. The impact of a reduced gravity and enhanced elemental abundances on cloud formation is to increase both the cloud extension, the concentration, and the size of dust grains into the atmosphere. We find that when planets differ from low gravity brown dwarfs, they can be explained by an over-abundance of elements. We also present the advancement in simulating a global gas giant planets, including dust formation and rotation with the CO5BOLD code. !

5.12 !Poster ! ✩✩✩✩✩Student David Armstrong University Of Warwick, UK Don Pollacco, & David Martin Circumbinary Exoplanets: Detection and Abundance Circumbinary exoplanets are planets orbiting around a close binary star. They are strange objects, with their formation and evolution subject to gravitational torques, variations in insolation and other effects not found in planets around single stars. These can lead to rapid orbital precession, with precessional periods on the timescale 5 of only tens of planetary periods. This along with the motion of the binary stars presents complications to their detection. Here we focus on the transit detection method, where transit timing variations (TTVs) on the order of days in magnitude become evident. We describe newly derived and tested limits on the TTVs of such planets, and a new search algorithm developed with these limits. Moving forward, we apply this method to the Kepler dataset with the aim of finding observational constraints on the abundance of circumbinary exoplanets. Where the abundance differs from the single star case, this represents a new window on planet formation, opening up how different formation pathways react to this variable environment.As part of the way to this abundance, we present a new catalogue of binary spectral fits for the stars of the Kepler Eclipsing Binary Catalogue. This will be a useful resource for those working with the exceptionally precise Kepler data of these interesting objects.!

5.13 !Poster ! ✩✩✩✩✩Student Gaspar Bakos Princeton University, USA et alia Planets with HATNet I will review the current status of HATNet, a network of small,wide-field telescopes. HATNet has been operational for 8 years,leading to the discovery of 44 transiting extrasolar planets.Properties of these planets span a wide range; masses from that ofNeptune to 10 times that of Jupiter, periods from 1 day to more than 10days, mean densities from one tenth to ten times that of water, orbits from aligned to retrograde, equilibrium temperatures from 700K to2700K. These planets are all around bright stars with V<14, making them amenable for follow-up studies. I will highlight some of the recent advances, discoveries and scientific results, and will comment on future developments.!

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5.14 !Poster Jason W. Barnes University of Idaho, USA Julian van Eyken, Brian K. Jackson, David R. Ciardi, & Jonathan J. Fortney Spin-Orbit Misalignment and Rapid Nodal Precession of the First Planet Transiting a Pre-Main-Sequence Star Van Eyken et al. (2012) discovered an exoplanet candidate in a tight 10.76-hour orbit around a low-mass (0.34-0.44 M_Sun) pre-main-sequence star in Orion, PTFO-8-8695b. Ground-based lightcurves of transits in 2009 and 2010 show different transit depths, durations, and shapes between the two years. We will show that the lightcurve variations are consistent with a planet precessing around an oblate, rapidly-rotating star. Rapid stellar rotation induces gravity darkening in the stellar disk where the poles appear hotter and brighter than the equator. This non-uniformity of the stellar disk allows us to measure the planet's projected spin-orbit angle lambda as well as the obliquity of the stellar rotation pole in both 2009 and 2010. Using a theoretical framework for precession in the case where the stellar rotation and planetary orbit angular momenta have similar magnitudes, we will show two different precession scenarios that can explain the lightcurves and their variation. The two scenarios yield planet masses of 3.0 M_Jup and 3.6 M_Jup, consistent with a radial velocity upper limit of 5.5 M_Jup from van Eyken et al. (2012), and which correspond to precession periods of 292.6 days and 581.2 days respectively. The evidence for planetary precession and the resulting measured masses validate PTFO-8-8695b as the first transiting planet around a pre-main-sequence star. It is the lightest, coldest, and youngest star for which a star-planet spin-orbit alignment has been measured (69 degrees and 73 degrees respectively for each scenario). This spin-orbit misalignment for such a young, close-in planet lends credence to the Winn et al. (2010) suggestion that Hot Jupiters' spin-orbit alignments are initially isotropic.Our proposed precession scenario has many opportunities for independent observational confirmation. (1) Over the course of the precession, transits should disappear for several months. (2) The orbit inclination changes should cause differences in the amplitude of planet-induced radial velocity variations. (3) Rotational broadening of stellar absorption lines (v sin(i)) should change as the orientation of the stellar rotation pole varies. (4) The projected spin-orbit alignment should vary between -80 degrees and +70 degrees, as could be seen via the Rossiter-McLaughlin effect. (5) The shape of the lightcurves from transit photometry should continue to vary in a predictable way. And (6) the transit lightcurves should show 5 different shapes at different wavelengths.!

5.15 !Poster Jo Barstow University of Oxford, UK Suzanne Agrain, Patrick Irwin, Leigh Fletcher, Neil Bowles,& Jaemin Lee From spectra to atmospheres: solving the underconstrained retrieval problem for exoplanets Spectroscopic observations of transiting exoplanets have provided the first indications of atmospheric structure and composition on planets orbiting stars other than the Sun. A technique used with great success to translate spectroscopic observations of solar system planets into information about their atmospheres is optimal estimation retrieval, and it has recently been applied to exoplanet transit spectra. I show the effectiveness of the technique when combined with simulated observations from the proposed space telescope EChO, and also discuss the difficulty of constraining a complex system with limited number and quality of data, using the super-Earth GJ 1214b as an example.When a planet passes in front of its parent star as seen from the Earth, the resultant reduction in the amount of observed starlight varies as a function of wavelength, depending on the absorptive properties of the planetʼs atmosphere; alternatively, when it is eclipsed by its parent star, a difference measurement can yield the planetʼs emission and/or reflection spectrum. However, a lack of a priori knowledge about the planetʼs bulk composition, cloudiness and temperature can make it difficult to find a unique solution to the underconstrained retrieval problem. The NEMESIS radiative transfer and retrieval tool (Irwin et al. 2008) allows this process to be explored, and it has been used to constrain the properties of exoplanets such as HD 189733b (Lee et al. 2012) for which a range of spectroscopic data exist. I will discuss the process of optimal estimation retrieval for exoplanet atmospheres with the aid of two examples. I will present the results of recent studies investigating the retrievability of atmospheric properties from both primary (transmission) and secondary (eclipse) transit spectra using the proposed EChO space telescope (Barstow et al. 2013). NEMESIS is used to generate a range of synthetic spectra based on model hot Jupiters and hot Neptunes; noise of the expected level is added to these, and then they are

67 Session 5: Detailed Studies of Known Exoplanets and Exoplanet Systems

fed back into NEMESIS and the atmospheric state retrieved. The retrieved and input atmospheric states are then compared, and the accuracy of the retrieval for different cases is determined. Secondary transit geometry probes the same atmospheric properties as a direct disc-integrated spectrum of an exoplanet, as it effectively provides a dayside emission spectrum. The techniques and results described here could therefore very easily be applied to direct spectroscopic imaging studies, also to spectra of cool brown dwarfs, and we find that EChO spectra should provide a good constraint for hot Jupiter and Neptune atmospheric temperatures and compositions within the limits of our model. The warm super-Earth GJ 1214b provides an excellent example of the complexities involved in solving the degenerate retrieval problem. The spectrum of this planet is remarkably featureless, indicating that the atmosphere must have either a high molecular weight and small scale height, or a high cloud layer that masks gaseous absorption features. I present best-fit model atmospheres and spectra based on the available primary transit observations, which show that there is insufficient information in the spectrum to constrain the planetʼs atmosphere. Several model atmospheres provide an equally good fit to the data, and in particular it is impossible to place a limit on the abundance of water vapour in the atmosphere. The future observation of GJ 1214b in secondary transit with more sensitive instruments than those currently available may well be necessary to definitively distinguish between the water-rich and miniature Neptune scenarios for this fascinating planet. The retrieval method is an extremely useful tool for the interpretation of exoplanet spectra, but a lack of a priori knowledge and the paucity of data complicate the process. A combination of this and other methods, e.g. ab initio calculation methods based on equilibrium physics assumptions, is likely to be necessary if these problems are to be overcome. References:Irwin et al.,”The NEMESIS planetary atmosphere radiative transfer and retrieval tool” JQSRT (2008)Lee et al. “Optimal estimation retrievals of the atmospheric structure and composition of HD 189733b from secondary eclipse spectroscopy” MNRAS (2012)Barstow et al. “On the potential of the EChO mission to characterise gas giant atmospheres” MNRAS (2013)!

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5.16 !Poster ! ✩✩✩✩✩Student Jean-Loup Baudino LESIA, Observatoire de Paris, France Bruno Bezard, Anthony Boccaletti, Anne-Marie Lagrange, & Mickael Bonnefoy A radiative-convective equilibrium model for young giant exoplanets: Application to beta Pictoris b We developed a radiative-convective equilibrium model for young giant exoplanets. Input parameters are the planet's surface gravity, effective temperature and elemental composition. Under the additional assumption of thermochemical equilibrium, the model predicts the equilibrium temperature profile and mixing ratio profiles of the most important gases. Opacity sources include the H2-He collision-induced absorption and molecular lines from H2O, CO, CH4, NH3, VO, TiO, Na and K. Line opacity is modeled using k-correlated coefficients pre-calculated over a fixed pressure-temperature grid. Cloud absorption can be added above the expected condensation level (e.g. iron or silicates) with given scale height and optical depth at some reference wavelength. Scattering is not included at the present stage.Model predictions will be compared with the existing photometric measurements of Planet Beta Pictoris b in the J, H, K, L and M bands(Lagrange et al. 2009; Quanz et al. 2010; Bonnefoy et al. 2011, 2013).This model will be used to interpret future photometric and spectroscopic observations of exoplanets with SPHERE, mounted at the VLT with a first light expected in Summer 2013. !

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5.17 !Poster Daniel Bayliss The Australian National University, Australia Gaspar Bakos, Zoltan Csubry, Kaloyan Penev, Andres Jordan, Joel Hartman, Thomas Henning, Bob Noyes, Bence Beky, Vincent Suc, Balazs Csak, Markus Rabus, Maren Mohler, Istvan Papp, Pal Sari, Peter Conroy, George Zhou, Brian Schmidt, Luigi Mancini, Dimitar Sasselov, & Miguel de Val Borro Transiting Exoplanets from HATSouth HATSouth is the worldʼs first network of automated and homogeneous telescopes that is capable of year-round 24- hour monitoring of positions over an entire hemisphere of the sky. The goal of the network is to discover and characterize a large number of transiting exoplanets, reaching out to long periods and down to small planetary radii. HATSouth also probes a population of lower mass stars including m-dwarfs which are not monitored in shallower exoplanet transit surveys.HATSouth monitors extended areas on the sky, deriving high precision light curves for a large number of stars, searching for the signature of planetary transits, and confirming and characterizing planetary candidates with larger telescopes. The project employs six telescope units spread over three prime locations with large longitude separation in the southern hemisphere: Las Campanas Observatory (Chile), HESS site (Namibia), and Siding Spring Observatory (Australia). Each of the HATSouth units holds four 0.18 m diameter telescope tubes on a common mount producing a 64 sq. deg. field-of-view on the sky.We will present an overview of the HATSouth network, summarize operations over the first 2.5 years, and present the current HATSouth exoplanet discoveries to date, including the characterization of these exoplanetary systems.!

5.18!Poster ! ✩✩✩✩✩Student Thomas Beatty Ohio State University , USA Scott Gaudi, Jason Eastman, Jonathan Fortney, Heather Knutson, Joshua Pepper, Robert Siverd, & Keivan Stassun Space- and Ground-based Secondary Eclipses 5 of the Highly Irradiated Transiting Brown Dwarf KELT-1b The transiting brown dwarf KELT-1b provides us with a unique opportunity to investigate the relation between brown dwarfs and exoplanets. It is a 27 Jupiter-mass object on a short 1.2 day orbit around a bright (V=10.8) F5V star. KELT-1b allows us to study a brown dwarf where we know the mass, radius and age -- in an environment similar to hot Jupiters and around a star bright enough to allow for precision follow-up observations. KELT-1b is also specifically interesting because it is substantially inflated as compared to models for brown dwarfs at the age of the KELT-1 system. This is the first instance of an inflated brown dwarf, and whether the inflation mechanism is related to that of hot Jupiters or low-mass stars is unclear. We observed secondary eclipses of KELT-1b at 3.6um and 4.5um using the Spitzer Space Telescope and in z-band using ground-based telescopes. While we do not detect the secondary from the ground, we strongly detect the 3 .6um and 4.5um eclipses. †We report on the results of these observations and their implications.!

5.19 !Poster ! ✩✩✩✩✩Student Kimberly Bott University of New South Wales, Australia Lucyna Kedziora-Chudczer, & Jeremy Bailey A VSTAR Model of the Hot Jupiter HD 189733b Past analysis of HD 189733b's atmosphere has been a cause for some debate, with conflicting findings regarding water and sodium abundances and the presence of a high altitude haze. I will present our modeling of HD 189733b's cloud structure and atmospheric composition using VSTAR (Versatile Software for Transfer of Atmospheric Radiation ). Since the effective temperature of the planet is expected to be approximately 5000K, newly available high-temperature spectral line lists are used. Our result will be compared to previous findings and an assessment of the practicality of a model-focused approach to exoplanet spectral analysis will be made.

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69 Session 5: Detailed Studies of Known Exoplanets and Exoplanet Systems

5.20!Poster Duncan Christie University of Virginia, USA Zhi-Yun Li & Phil Arras H-Alpha Absorption in Transiting Exoplanet Atmospheres While Lyman-alpha absorption provides a probe of the hydrogen content of an exoplanet atmosphere, the recent observation of H-alpha absorption by the atmosphere of HD189733b provides an opportunity to probe the thermal structure of the atomic hydrogen. With this in mind, I will discuss the relative importance of the various creation and destruction pathways for n=2 hydrogen -- collisional excitation, photoionization, radiative recombination, as well as radiative transitions -- and present a spherically-symmetric, hydrostatic model of the atmosphere of HD189733b capable of reproducing the observed absorption signal. Additionally, I will address the role of stellar Lyman-alpha in setting the n=2 abundance and its influence on the Lyman-alpha cooling rate. !

5.21!Poster René Doyon Université de Montréal, Canada M. E. Naud, E. Artigau, L. Malo, L Albert, D. Lafrenière, & J. Gagné Discovery of a planetary mass compagnon around a young low-mass star We present the discovery of planetary-mass companion found 2000AU from a M3 star, member of the young (50-120 Myr) AB Doradus moving group. It was identified through an ongoing survey with GMOS at Gemini-South, via its distinctively red i-z color. The comoving status of this object was confirmed by 2 epochs of WIRCam/CFHT J- 5 band images. The NIR photometry and WISE colors suggest an early-to-mid T bound companion. A NIR spectrum, taken with GNIRS at Gemini-North, confirms a mid-T spectral type. With an estimated temperature between 900K and 1200 K, models predict a mass between 7 and 12 MJup for this object. The benchmark character of this planetary-mass object lies in its well-constrained age and in its very wide separation, that allows in-depth studies that can help validating models and understanding similar but closer-in companions such as the ones that will be uncovered by next-generation planet finders.

5.22 !Poster Keigo Enya ISAS/JAXA, Japan Characterization of exoplanet atmosphere with a space infrared telescope Monitor observation of transiting exoplanets is one of important method for characterization of exoplanet atmosphere. There are many absorption features of exoplanet atmospheres in the infrared wavelength region. For the characterization of transiting exoplanets by spectroscopic monitoring, stability of the observation is essential because the spectral features of exoplanets are derived as the difference between the transit-in and the transit-out. Therefore, a space infrared telescope is useful tool. This poster presents a conceptual design for a spectrometer designed specifically for characterizing transiting exoplanets with space infrared telescopes. The design adopting cross-dispersion is intended to be simple, compact, highly stable, and has capability of simultaneous coverage over a wide wavelength region with high throughput. Typical wavelength coverage and spectral resolving power of a spectrometer made of such dispersers are 1-13 micron and ~ hundred, respectively. The effect of defocusing is evaluated. Variations in the design, and comparison with spatially-resolved observation are discussed briefly.!

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5.23!Poster Francesca Faedi University of Warwick, UK Yilen Gomez Maqueo Chew, Luca Fossati, Don Pollacco, Amy McQuillan, Mike Goad, Leslie Hebb, William J. Chaplin, & Suzane Aigrain The SOAPS project: Spin-Orbit Alignment of Planetary Systems The wealth of information rendered by Kepler planet candidates is indispensable for statistically significant studies of distinct planet populations, in both single and multiple systems. Empirical evidences suggest that Kepler's planet population shows different physical properties as compared to exoplanets detected from the ground. The SOAPS project, aims to shed light on Kepler's planets formation, their migration and architecture. By measuring vsini accurately for Kepler hosts with rotation periods measured from their high-precision light curves, we will assess the alignment of the planetary orbit with respect to the stellar spin axis. This degree of alignment traces the formation history and evolution of the planetary systems, and thus, allows to distinguish between different proposed migration theories. SOAPS will increase by a factor of 2 the number of spin-orbit alignment measurements pushing the parameters space down to the SuperEarth domain. I will present and discuss our results of the first Subaru/HDS observations.!

5.24!Poster ! ✩✩✩✩✩Student Eric Gaidos University of Hawaii at Manoa, USA & Andrew W. Mann A Palatable Planetary Porridge: 5 Candidate Planets in the Habitable Zones of Kepler Stars The Kepler mission's primary objective is the discovery of Earth-size transiting planets in "habitable zones" where stellar irradiance maintains a temperate climate on an Earth-like planet. Robust estimates of planet radius and irradiance require accurate stellar parameters, but most Kepler systems are faint, making spectroscopy difficult and prioritization of targets desirable. The parameters of2035 host stars are estimated by a Bayesian comparison of photometry with synthetic photometry from the Dartmouth Stellar Evolution models and priors for stellar mass, age, metallicity, distance, and planet transit duration. This produces probability density functions for the radius and stellar irradiance of 2738 candidate or confirmed planets. The probability pHZ that the irradiance falls between the wet runaway greenhouse and carbon dioxide condensation limits - the canonical boundaries for the habitable zone - is calculated. Sixty-two planets have pHZ > 0.5 and a most probable stellar irradiance within habitable zone limits, and fourteen of these have radii less than twice the Earth. A similar analysis of >120,000 dwarf stars in the Kepler target catalog returns the probability that a planet in the habitable zone of each star would transit and be detected. These probabilities are used in a binomial likelihood calculation to estimate the fraction of Kepler dwarf stars with planets greater than two Earth radii in the habitable zone (0.33). Based on a planet radius distribution found by others, we find that the fraction of dwarf stars with Earth-size planets in the habitable zone is 0.46, with a 95% confidence interval of 0.31-0.64. The objects most resembling Earth in terms of radius and irradiance are KOIs 2626.01 and 3010.01, which orbit late K- or early M-type dwarfs. However, in the absence of parallaxes, irradiance estimates are extremely sensitive to the effective temperatures assigned a star, and accurate temperature assignments to such very cool dwarfs are problematic. We present a new calibration of visible- wavelength spectroscopy accurate to 60 K based on nearby dwarfs for which radii and luminosities are independently known and hence effective temperatures are available. We apply this to Kepler late K- and M-type dwarfs, re-assess the irradiance of their planets, and re-estimate the fraction of these stars with planets in the habitable zone. Parallaxes from the upcoming Gaia mission will reduce uncertainties in radius and irradiance by more than a factor of five and permit even more definitive assignments of transiting planets to the habitable zones of Kepler stars.!

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5.25!Poster! Yilen Gómez Maqueo Chew Vanderbilt/Warwick, USA/UK Francesca Faedi, Leslie Hebb, Phillip Cargile, Luan Ghezzi, Amanda Doyle, Susana Barros, Sergio Sousa, Andrew Collier Cameron, Don Pollacco, Nuno Santos, Barry Smalley, & Keivan Stassun The HoSTS Project: Homogeneous Study of Transiting Systems The Homogeneous Study of Transiting Systems (HoSTS) will derive a consistent and homogeneous set of both the stellar and planetary physical properties for the entire sample of bright transiting planetary systems with confirmed planetary masses and measured radii. Our resulting catalogs of the fundamental properties of these bright planets and their host stars will enable us to explore empirical correlations that will lead to a better understanding of planetary formation and evolution, e.g., core-size versus stellar metallicity. We present our pilot study of the planet hosting star WASP-13, and some of our preliminary results on the larger sample. !

5.26!Poster Philip Gregory University of British Columbia, Physics and Astronomy Dept., Canada Samantha Lawler, & Brett Gladman Additional Keplerian Signals in the HARPS data for Gliese 667C from a Bayesian Re-analysis A re-analysis of Gliese 667C HARPS precision radial velocity data was carried out with a Bayesian multi-planet Kepler periodogram (from 0 to 7 planets) based on a fusion Markov chain Monte Carlo algorithm. The most probable number of signals detected is 6 with aBayesian false alarm probability of 0.012. The residuals are shown to be consistent with white noise. The 6 signals detected include two previously reported with periods of 7.2 and 28.1 days, plus additional periods of 30.8, 38.8 , 53.2, and 91.3 days. The existence of the additional Keplerian signals suggest the possibility of further planets although it is also possible that digging deeper with a more 5 powerful statistical algorithm might have uncovered new spectral artifacts of the measurement system or of the star's surface activity. In particular,the 53 day signal is probably the second harmonic of the stellar rotation period and is likely the result of surface activity.N-body simulations are underway to determine which of the remaining signals are consistent with a stable planetary system. At present,starting from the MCMC derived parameter sets we have not found a long term (10^7 yr) stable 5 planet system consistent with the data. If we assume the 30.8 d period is a spectral artifact, we are able to identify a long term stable system with periods of 7.2,28.1, 38.8, and 91.3 d. The corresponding M sin i values are 5.4,4.8, 2.4, and 5.4 ME and the semi-major axes inferred for the 28 and38.8 d signals place them in the central region of the habitable zone.Further analysis is underway to define the probability bubble of stable orbits corresponding to this candidate 4 planet system.!

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5.27!Poster Leslie Hebb University of Washington, USA Suzanne Hawley, Eric Agol, & Woody Austin Observing Starspots on Kepler Transiting Planet Host Stars We recently completed the development of an eclipse mapping code designed to derive the evolution of the stellar surface brightness using time series photometry of a transiting planet host star which shows starspot features during transit events. The program uses a Monte Carlo Markov Chain sampling technique to solve for the optimal starspot configuration that reproduces the observed short cadence Kepler light curve of a transiting planet candidate. Unlike other programs designed to model starspot crossing events, our program models both the in and out of transit data to provide a consistent picture of the overall starspot configuration. Here, we apply our code to our test target, Kepler-17. Our goal is to derive the decay timescale for starspot groups on Kepler-17 which is a solar analog with twice the rotation period as the Sun. This analysis constraints the flux transport timescale, an important parameter in dynamo models, which has not yet been measured for stars other than the Sun.!

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5.28!Poster Tobias C Hinse Korea Astronomy & Space Science Institute (KASI), South Korea Dynamics & synthetic modeling of the light-travel time effect of circumbinary extrasolar planets In recent years several single and multi-body extrasolar planets (aka circumbinary companions) have been announced to orbit short-period eclipsing binaries from measuring the time of mid-eclipses. A dynamical analysis of these systems reveal that the derived best-fit orbital elements result in unstable orbits on short time scales. Here, we present results from modelling synthetic timing data set of stable circumbinary planetary systems and discuss their implications.!

5.29!Poster ! ✩✩✩✩✩Student John Hodgson II California State University, Northridge, USA Damian Christian, Dennis Bodewits, & Suzanne Hawley Using exoplanet systems with highly elliptical orbits to search for star-planet interactions We have undertaken a study to determine if the orbital geometry of the exoplanets affects the activity of their host star by studying a sample of planetary systems known to contain massive planets on short period, highly elliptical orbits. While recent studies in the optical, UV, and X-Ray have shown enhanced chromospheric activity for stars hosting exoplanets with orbital semi-major axes less than 0.1 AU [1, 2, 3, 4], it is not yet clear whether this activity is driven by magnetic or tidal interaction. We are probing the dependence of star-planet interactions on the orbital geometry of the planetary systems by analyzing the Ca II H & K emission lines for variability phased with the exoplanet's orbit. We have obtained high resolution spectra of several systems with the McDonald 2.1m Sandiford echelle spectrograph and ARCES on the APO 3.5m. We shall describe our methodology and then review our results on how orbital geometry can be used to study how planets may affect the activity of their host stars.References[1] Krejcova, T., & Budaj, J., 2012, A&A, 540, A82[2] Shkolnik, E., 2013, ApJ pre-print from arXiv: 1301.6192v1[3] Kashyap, V.L., Drake, J.J., & Saar, S.H., 2008, ApJ, 687, 1339[4] Poppenhaeger, K., Robrade, J., 5 & Schmitt, J.H., 2010, A&A, 5 1 5 , A98!

5.30!Poster Derek Homeier Ecole Normale Supérieure de Lyon, France France Allard, & Bernd Freytag Internally consistent 1D atmosphere models and local hydrodynamic simulations as a tool for exoplanet analysis Transit spectroscopy, and increasingly spectroscopic analysis of directly imaged planets, are becoming important tools for the study of atmospheric properties and composition of extrasolar planets, and by way of this providing the only directly accessible information on the overall composition and history of planets. However the direct retrieval of atmospheric parameters from observed data is typically challenged by the degeneracy of the vertical temperature and pressure profile and mixing ratios of a potentially large number of chemical constituents, that are to be constrained by only a few data points. I shall discuss the insight that internally consistent atmosphere models can provide in this situation, which are fundamentally based on the principles of energy and mass conservation and chemical and local thermodynamic equilibrium as employed in classical stellar atmosphere theory. In our models for ultracool stellar and brown dwarf atmospheres, departures from these constraints are enabled for certain key parameters and processes and calibrated by comparison with time-dependent radiative hydrodynamic simulations as well as tests on high resolution and high S/N observations. This grid of PHOENIX 1D model atmospheres, making use of dynamical properties inferred from CO5BOLD RHD simulations, has successfully reproduced the formation and disappearance of clouds in brown dwarfs, thus explaining the L-T transition, and the departures from chemical equilibrium found in cool brown dwarfs. When applied to low-gravity objects, our model can also explain the particular cloudiness of even cooler young exoplanets as well as some apparent peculiarities in their chemical composition. I will discuss the potential application of these models to an even wider range of both gas giant and

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super-Earth exoplanets together with the impact of different base (elemental) abundances and the possible relevance of large scale circulation on their atmospheric dynamics.! 5.31!Poster Jonti Horner University of New South Wales, Australia Robert Wittenmyer, Chris Tinney, Paul Robertson, Tobias Hinse, & Jonathan Marshall Dynamical Constraints on Multi-Planet Exoplanet Systems As a direct result of ongoing efforts to detect more exoplanetary systems, an ever-increasing number of multiple- planet systems are being announced. But how many of these systems are truly what they seem? In many cases, such systems are announced solely on the basis of orbital fits to observational data, and no attempt is made to see whether the proposed orbits are actually dynamically feasible. As a result, it is certain that "planetary systems" are being announced that involve planets moving on orbits that would be dynamically unstable on timescales of just a few hundred years. Here, we present the results of detailed dynamical simulations that investigate the orbital stability and evolution of a number of recently announced multi-planet exoplanetary systems. These simulations have enabled us to create highly detailed dynamical maps of those systems, allowing us to better constrain the orbits of the planets contained therein. In some cases, our results have even led to the very existence of the planets themselves being called into question. !

5.32!Poster ! ✩✩✩✩✩Student Xu Huang Department of Astrophysical Science, Princeton, USA Gaspar Bakos, & Joel Hartman On improving the yields of transiting planets in HATNet with Kepler data as a calibrator The HATNet project is a wide-field ground-based search for transiting planets around moderately bright stars. Like other wide-field ground-based transit surveys, HATNet is primarily sensitive to giant planets with orbital periods less than ~10 days. In an attempt to improve our yield of smaller and longer period planets we use the transiting planet candidates from the Kepler space mission that have been observed by HATNet to calibrate a new transit detection 5 pipeline. The Kepler field was observed by HATNet prior to the launch of the mission, resulting in the discovery of HAT-P-7b and HAT-P-11b. Now as a result of Kepler, we know the distribution of planet candidates far below the sensitivity threshold of HATNet. We select the bright Kepler candidates observed by HATNet with periods less than20 day and radii larger than that of Neptune. We search the HATNet light curves using a method that includes initial de-trending of the data, the reconstructive trend filtering algorithm (TFA) together with the Box Least Squares (BLS) method, and a phase space transit fitting method. The reconstructive TFA is an iterative noise filtering algorithm making use of the information obtained from BLS. We include possible transit signals as an additional template besides the typical sets of templates from stars in the same fields. The phase space transits fitting is specifically designed for the discontinuous data of ground-based light curves, aiming to separate the contribution to the signal from a single outlier from that of a real transit and then enhancing the signal-to-noise of the real transit by allowing for transit timing variation. The new pipeline yields robust detections for several of the Kepler candidates that were previously not selected by HATNet (for instance, KOI1347.01 with a period of 14.4 days). We estimate the potential future detections in other HATNet fields based on this result by assuming the underlying plant distribution implied by the Kepler data.!

5.33 !Poster ! ✩✩✩✩✩Student Marshall Johnson University of Texas at Austin, USA & William Cochran Doppler Tomographic Observations of KOI-13 b We present Doppler tomographic observations of the transiting planet KOI-13 b, a highly inflated hot Jupiter orbiting the Teff=8500 K primary of a hierarchical triple system. As the planet transits the rapidly rotating host star, it successively blocks regions of the stellar disk with different radial velocities, causing a “bump” in the spectral line shape, which we spectroscopically resolve. The manner in which this perturbation moves across the stellar line during the transit gives information on the relative alignment between the stellar spin and planetary orbital angular momentum vectors. This is a powerful statistical probe of planetary migration processes, as the expected spin-orbit misalignment distributions from dynamically cold migration (disk interactions) and dynamically hot migration (planet-planet scattering, Kozai cycles) are significantly different. Doppler tomography also promises to be a

74 Session 5: Detailed Studies of Known Exoplanets and Exoplanet Systems powerful technique for confirming transiting planet candidates around rapidly rotating stars like KOI-13 A, which are not amenable to radial velocity follow-up and thus are currently a poorly sampled region of parameter space. 5.34!Poster Daniel Jontof-Hutter NASA Ames Research Center, USA Jack Lissaauer, & The Kepler TTV Multiplanets Group Filling in the Mass-Radius Diagram for Super-earths and Sub-Neptunes The bounty of exoplanet discoveries has made the question of planet formation one of widespread interest and renewed urgency in astronomy. Characterizing exoplanets, their compositions and orbital configurations, is the first step to evaluating formation scenarios. To this end, the mass-radius relation for planets is crucial. Filling in the mass-radius diagram for super-earths and sub-neptunes will be particularly useful, since the solar system leaves a wide gap in planetary sizes and densities in this regime. The aim is to understand both the trends and the scatter in the mass-radius relation. Of particular interest are the multiplanet systems, where we may be able to compare density gradients to our solar system, as well as the minimum mass of material available during the formation epoch.Outside our solar system, there are few planets with known masses and radii, mostly hot jupiters whose radii are known from transit depths, and whose masses are determined from radial velocity spectroscopy (RV). In the absence of mass determinations via RV observations, transit timing variations (TTVs) offer a chance to probe perturbations between planets and hence measure planetary masses and orbital parameters. The advantage of TTVs for populating the mass-radius diagram is that the same observational sample of planetary candidates from Kepler have known or well-constrained planetary sizes, and thus planetary densities can be determined. Here we evaluate the strengths and limitations of the TTV method in yielding useful constraints on masses, radii, and orbital parameters beginning with the six planet system of Kepler-11 (Lissauer et al 2013), by fitting dynamical models to the transit timing data.Dynamical fits can test orbital parameters, including the eccentricity vectors, which, alongside the transit lightcurves can tightly constrain the stellar density, as well as the transit impact parameters and mutual orbital inclinations. In Lissauer et al (2013), we found that dynamical fits to the TTVs of Kepler-11, particularly Kepler-11 d, e and f, provided tight constraints on the planetary orbital parameters including the eccentricity vector e sin w, where w is the argument of periapse. These, alongside spectroscopic data on the host star permitted a substantial reduction in the uncertainty on the mass and radius of the star, and hence the planets too. In the absence of asteroseismology detections, dynamical models provide the tightest 5 constraints on stellar parameters.Although dynamical fits to TTV data can probe planets less massive than RV targets, measuring masses with TTVs is not without its difficulties. Firstly, exploring parameter space to find a best fit model is numerically expensive. Neglecting mutual inclinations, parameters include masses, orbital periods, phases and eccentricity vectors for each planet. These are modeled against Keplerʼs growing dataset of transit times, which already includes hundreds of transits for some planetary candidates. Furthermore, the Chi-square surface may be plagued by multiple local minima. To overcome this, a thorough exploration of initial parameters is required to increase confidence that the best local minimum is also the global best fit. Finally, there is a degeneracy between mass and eccentricity in the pairwise interactions of neighboring planets. In Lissauer et al (2013), we found that the innermost pair of planets at Kepler-11 are largely dynamically isolated from the others, and suffer from this degeneracy. This means that both masses and eccentricities for these planets are poorly constrained. It remains unclear just how many well-constrained mass determinations will be made from the Kepler sample, and how well the smaller planets, namely the super-earths or earths, will be characterized. To this end, we begin by presenting our results for Kepler-11, and follow up with measured radii and masses on a handful of additional systems, gleaning what constraints we can on densities and hence compositions. !

5.35!Poster Quinn Konopacky Dunlap Institute, Canada Carbon and Oxygen in the Spectrum of HR 8799c The field of exoplanet spectroscopy has grown tremendously in the last decade. With the discovery of gas giant planets at wide separations from their host stars via direct imaging, it is now possible to obtain exoplanet spectra with unprecedented spectral resolution. We present a medium resolution spectrum of the directly imaged exoplanet HR 8799c. This K band spectrum was obtained using the integral field spectrograph OSIRIS on the Keck II telescope. Our spectrum shows numerous, well-resolved molecular lines from water and carbon monoxide (CO). There is no clear evidence for methane absorption, in spite of a best fit temperature of ~1100 K. We find a best fit surface gravity log(g) ~ 4.0, consistent with the inferred young age for the system (~30 Myr), and a continuum morphology consistent with

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previously-inferred dust clouds. Using the water and CO lines, we are able to estimate the C/O ratio for this planet. We find a ratio slightly higher than stellar (~0.65), which provides hints about the planet's formation. 5.36!Poster Anne-Marie Lagrange IPAG, France G. Chauvin, H. Beust, M. Bonnefoy, A. Boccaletti, J. Milli, et al Orbit of beta Pictoris Young systems such as beta Pictoris are of great importance as they trace the formation and early evolution of planetary systems. They are also the only targets around which planets can be imaged today. We detected withNaCo a giant planet around beta Pictoris (Lagrange et al, 2009, A&A, 493, L21; 2010, Science, 329, 57), roughly along the dust disk position angle (PA), with a semi-major axis (sma) between 8 and 14 AU. Its observed L' luminosity indicated a 1700 K, 7-11 MJup mass planet according to "hot-start" models (Bara ffe et al, 2003, A&A, 402, 701). Follow-up observations at 4.05 microns (Quanz et al, 2010, ApJ, 722, L49) and at 2.18 microns (Bonnefoy et al, 2011, A&A, 258, L15) confirmed these values. Beta Pictoris b was also detected in archival NICI images (Boccaltti et al, 2013, AA, 551, L14). Recent NaCo images of impressive quality allowed us to reconstruct beta Pic b spectral energy distribution over the 1.26-4.78 micron range, and to constrain its physical properties (see Bonnefoy's et al talk).Thanks to its short period, beta Pictoris b orbit can be well constrained using direct imaging and radial velocity data. We will show the results of the analysis of its astrometric monitoring, and discuss the implications on several aspects that make the beta Pictoris system a very peculiar one, in particular, the connection with the disk, and the presence of falling evaporating exocomets.!

5.37!Poster Yoram Lithwick Northwestern University, USA 5 Wu Yanqin, & Xie Jiwei Planet Mass and Eccentricity from TTV Transit time variations (TTVs) can be used to infer the masses and eccentricities of exoplanets.We show how observed TTV's can be simply inverted to infer the planets' properties; we also show what degeneracies arise and how they may be removed.Applying our techniques to TTV's observed by Kepler, we determine the mass-radius relation for dozens of planets, and also show that most of these planets have very small eccentricities (<0.01). The small eccentricities suggest that many of these planets experienced substantial dissipation, and is consistent with our proposed mechanism of "resonant repulsion" to explain the pile-up of Kepler pairs just wide of resonances.We discuss the implications for the formation and evolution of Kepler-like planetary systems.!

5.38!Poster Cezary Migaszewski Torun Centre for Astronomy, Poland Mariusz Slonina, & Krzysztof Gozdziewski Photodynamical analysis of transits in multiple planet systems The Kepler mission is a breakthrough in the field of detecting low-mass extrasolar planets through the photometric technique. Because the parent stars are usually faint, the spectroscopic follow-up of Kepler candidates is either very difficult or basically impossible. Yet transiting planets in multiple systems might be confirmed by the dynamical approach, which makes use of the Transit Timing Variation effect. In this work, we consider the so called photo- dynamical analysis of such systems. This approach,announced in our recent paper (Migaszewski et al. 2012), is a refined,original variant of the TTV method combined with a quasi-global dynamical mapping of the phase space with the help of fast indicators. It relies onCPU-efficient direct fitting of the light curves. It enables us to determine true planetary masses as well as eccentricities and orbital angles. The method is robust, as we demonstrated on the example of Kepler-11 system that consists of 6 planets in the Earth-mass range. The physical and dynamical properties of this complex system are discussed. We show that the relative inclinations between orbits of planets b

76 Session 5: Detailed Studies of Known Exoplanets and Exoplanet Systems and c as well as d and e can be constrained by the new algorithm with the precision reaching 2 degrees, in spite of relatively narrow observational window. We confirm and improve the determination of masses of five inner planets in the discovery paper (Lissauer et al. 2011), as well as we show that the mass of the outermost planet g can be constrained to less than 30 Earth masses. We found a clear anti-correlation between mean densities of all six planets and their distances from the star. It might reflex the formation and early evolution of the system and it might be a common feature of the multiple systems in the Kepler sample. The determination of the initial condition of the system is accompanied by detailed analysis of its architecture through extensive use of the so called dynamical maps. The massive computations are conducted with our new CPU cluster framework relying on the Message Passing Interface technique. We found that the phase space of the Kepler-11 system exhibits a structure of the Arnold web and its dynamics are governed by a dense net of multiple mean motion resonances. We also consider other complex configurations similar to the Kepler-11 planetary system.!

5.39!Poster ! ✩✩✩✩✩Student Matthias Müller Leibniz-Institute for Astrophysics Potsdam (AIP), Germany Klaus Strassmeier, Ignasi Ribas, & Thorsten Carroll Ground-based Transmission Spectroscopy of Highly-Inflated Hot Jupiters Transmission spectroscopy of transiting planets is one of very few methods to probe the atmosphere of an extrasolar planet. Different chemical elements and compounds have already been found in the highest unbound atmospheric layers and also in lower regions by this technique. Furthermore, measurements have been made which can be interpreted as the Rayleigh scattering signatures from haze layers of condensed silicates. The detectability of an atmospheric signal increases with the brightness of the host star, the radius ratio of planet and star and the height of the planetary atmosphere. With more and more transiting planets found in the past years, also the number of planets favorable for transmission spectroscopy reached numbers which allow for a 5 comparative study of the atmosphere of Hot Jupiters. We conducted spectroscopic transit observations of a small sample of close-in gas giants with highly-inflated atmospheres using low-resolution multi-object spectrographs at the GranTeCan, the VLT and the LBT. We concentrated on the optical wavelength region covering the resonant lines of the alkali metals sodium and potassium and obtained simultaneously to the spectrum of the target also the spectra of one or multiple comparison stars. Here we present an overview of our observations and first results of planetary transmission spectra as planet-star radius ratio versus wavelength.!

5.40!Poster ! ✩✩✩✩✩Student Abhijith Rajan Arizona State University, USA Jenny Patience, Paul Wilson, Frederic Pont, & Robert De Rosa Searching for Photometric Variability across the L, T & Y Dwarf Sequence With the discovery of Y dwarfs by the WISE mission, the population of field brown dwarfs now extends to objects with temperatures comparable to those of Solar System planets. To investigate the atmospheres of these ultracool brown dwarfs with temperatures covering the range of transiting and directly imaged planets, we have monitored a sample of 83 L, T and Y brown dwarfs for infrared photometric variability. This survey was conducted in the J-band using both the SOFI camera on the 3.5 NTT and the SWIRC camera on the 6.5-m MMT. Each target was observed for a period ranging from 2.0 hours to 6.0 hours, covering a significant fraction of the expected rotation period. Breakup of the iron and silicate clouds into a patchy cloud layer has been suggested as an explanation of several large variables identified at the L/T transition, and a similar process with sulfide clouds may be manifest in T/Y transition objects; our data provides the first test of these patchy cloud scenarios across the entire brown dwarf spectral range. !

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5.41!Poster Paul Rimmer University of St Andrews, UK Catherine Walsh, & Christiane Helling Cosmic Rays, UV Photons, and Haze Formation in the Upper Atmospheres of Hot Jupiters Cosmic ray ionization has been found to be a dominant mechanism for the formation of ions in dense interstellar environments. Cosmic rays are further known to initiate the highly efficient ion-neutral chemistry within star forming regions. In this talk we explore the effect of both cosmic rays and UV photons on a model hot Jupiter atmosphere using a non-equlibrium chemical network that combines reactions from the UMIST Database for Astrochemistry, the KIDA database for interstellar and protoplanetary environments and three-body and combustion reactions from the NIST database and from various irradiated gas planet networks. The physical parameters for our model atmosphere are based on HD 189733 b (Effective Temperature of 1000 K, log g = 3.3, solar metallicity, at a distance 0.03 AU from a K dwarf). Cosmic rays ionize molecular hydrogen, forming H3+, which in turn leads to the formation of complex hydrocarbons, C2H2 and CnH radicals. These species are thought to be the building blocks of Polycyclic Aeromatic Hydrocarbons (PAHs) found in the atmospheric hazes of e.g. Titan. The active UV photochemistry high in our model hot Jupiter atmosphere tends to destroy these hydrocarbons, but on a time-scale sufficiently slow that PAH formation could already have taken place. PAHs have many more internal degrees of freedom than the simpler hydrocarbon species, and should therefore be able to survive UV photons far more effectively. In most cases, carbon-bearing species formed by cosmic rays are destroyed by UV photons (e.g. C2H2, C2H4, HC3N). Conversely, carbon-bearing species enhanced by an active photochemistry are depleted when cosmic ray ionization is significant (e.g. CN, HCN and CH4). Ammonia is an interesting exception to this trend, enhanced both by an active photochemistry and a high cosmic ray ionization rate. Our model predicts an ammonia mole fraction of ~10-5 within the haze of HD 189733 b. We will conclude this talk with a discussion of the practical benefits of applying techniques and networks from chemical modeling of star-forming regions to fully formed 5 planetary atmospheres. Methods like this will be a first step toward modeling the formation of a planetary atmosphere from protoplanetary materials.!

5.42!Poster ! ✩✩✩✩✩Student John Rostron University of Warwick, UK & Peter Wheatley Testing the effects of metallicity on the atmospheric chemistry of exoplanets Characterisation of highly-irradiated exoplanet atmospheres through secondary eclipse observations has revealed a dichotomy. While the thermal emission of some of these planets display spectral features in absorption, consistent with an atmospheric temperature that falls off with altitude, many others have signatures consistent with stratospheric temperature inversions. The mechanism driving this split is not well understood. Initial work suggested insolation levels were the key, but more recent observations have not been consistent with this, implying other factors are important. One possibility still being debated is that a planet's metallicity content has a significant effect on its temperature profile. We present a study of Spitzer secondary eclipse measurements of 6 systems, designed to test whether such a relation is supported by observations. The systems, discovered by the Wide Angle Search for Planets (WASP) project, cover a range of host star metallicities, and we search for evidence of a correlation between this property and the inverted/non-inverted nature of the temperature profiles. Each of our targets has been observed in at least 2 channels of Spitzer's Infrared Array Camera and we detect thermal emission signatures from each planet in each observed channel. Using these results we characterise the presence

78 Session 5: Detailed Studies of Known Exoplanets and Exoplanet Systems or absence of temperature inversions, however our sample does not provide compelling evidence for a correlation with host star metallicity.!

5.43!Poster Evgenya Shkolnik Lowell Observatory, USA & Travis Barman HAZMAT: Habitable Zones and M dwarf Activity across Time With the recent discoveries of several super-earths orbiting M dwarfs well within the habitable zone (HZ; 0.1 to 0.4 AU), and with many more HZ planets (and moons) to come, it is time to determine whether these planets can really be habitable. Having a planetary atmosphere is a necessary condition to habitability. If the highincident ultraviolet (UV) light from the M dwarf destroys the planet's atmosphere, the planet will be left a barren rock. To assess the true danger to habitability from the high-energy radiation of the parent M star we start by mapping the evolution of the near-UV (NUV) and far-UV (FUV) flux over critical planet formation and evolution time scales. For these we use NUV (1750-2750Å) and FUV (1350-1750Å) photometry from NASA's Galaxy Evolution Explorer (GALEX) of M dwarf members of clusters or young moving groups (YMG) of known age. Here we we present the UV drop with age of a sample of well-characterized members of YMGs and old-field stars, including TWA members at 10 Myr old, coinciding with the onset of terrestrial planet formation, to the several-Gyr-old GJ 667 C, which hosts a super-earth within its HZ. These data also provide much-needed constraints to M dwarf upper-atmosphere models, which are insufficient at predicting UV emission from M dwarfs. Our analysis will produce an empirically motivated chromospheric profile for the young and old M dwarfs, which can then be used to predict the extreme-UV (EUV) fluxes most critical to the evolution of a planetary atmosphere. Our HAZMAT program is the first comprehensive study of the UV history of M stars, and will ultimately tell us if a planet in the canonical HZ can indeed be habitable.

! 5.44!Poster! Alexis Smith Copernicus Astronomical Centre, Warsaw, Poland 5 Probing the atmospheres of giant planets with occultation measurements When a transiting planet is occulted by its host star, we can detect the emergent flux from the planet. Near-infrared measurements of the occultation depth yield the brightness temperature of the system at a particular wavelength, which can provide an estimate of the efficiency of the heat redistribution to the night-side of the planet. Measurements of the occultation depth at several wavelengths allow the construction of a spectral energy distribution for the planet and enable the atmospheric composition and structure (for instance whether or not the atmosphere has a thermal inversion or stratosphere) to be inferred.In addition to using the Spitzer Space Telescope to obtain occultations redwards of 3.6 microns, we have an ongoing programme using several ground-based telescopes at shorter wavelengths. These observations are often vital to limit the range of models which can describe the atmospheric structure and composition. Of particular interest is what determines whether a particular planet's atmosphere exhibits a thermal inversion. Various parameters have been proposed as key to this question, including insolation, stellar activity and stellar metallicity. By characterising the atmospheres of hot Jupiters occupying a range of parameter space, we aim to resolve this question. Here we present our latest observational results.!

5.45 !Poster ! ✩✩✩✩✩Student Johanna Teske University of Arizona, Steward Observatory, USA Simon Schuler, Katia Cunha, Verne Smith, & Caitlin Griffith C/O Ratios of Stars with Transiting Hot Jupiters: Connecting Stars to Planets A planet's C/O ratio reveals information about its formation and evolution, with a C/O>0.8 resulting in a carbon-rich composition versus the silicate-dominated composition of Earth (C/O_solar~0.5) In forming exoplanet systems, the predefined initial gas composition is to first order that of the host star; under this assumption the star and planet will

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show similar abundance signatures. However, close-in giant planets are thought to form in outer protoplanetary disk regions from icy planetesimals that coalesce to form a core, followed by gas accretion and inward migration. The C/O ratio of a planet can thus be altered during its formation process from that of the host star by the different chemical gradients within the protoplanetary disk. While most exoplanet models assume a solar chemical abundances and C/O ratio (~0.5), relaxing this leads to drastic differences in the partitioning of carbon and oxygen in the atmosphere and interior of the planet. Recent results suggest a C/O>1 in the atmosphere of one of the most highly irradiated exoplanets, WASP-12b; this is particularly peculiar given the host star's C/O~0.40, and introduces the possibility of a sample of carbon-rich exoplanets. It raises the question, "Are the atmospheres of exoplanets and their host stars comprised of the same material, and if not, what makes them different?" Here we present observations of the stellar C/O ratios for a sample of host stars of transiting exoplanets (whose atmospheres can be characterized by transit/eclipse observations) to investigate the connection between star and planet compositions.!

5.46!Poster Feng Tian Tsinghua University, China Kevin France, Jeffrey L. Linsky, Pablo J.D. Mauas, & Mariela C. Vieytes Atmospheric Oxygen Abundances as False Positive Biosignatures for Habitable M dwarf Exoplanets Searching for life around M dwarfs are considered the fast track to find a second Earth. However, the FUV and NUV spectra of M dwarfs are dramatically different from solar-type stars. For example, recent observations of six weakly active M dwarfs show that the ratios between the integrated energy fluxes in FUV and NUV wavelengths are at least 1000 times greater than that of the Sun. Photochemical simulations show that such low NUV flux and high FUV flux could raise the atmospheric concentrations of O2 and O3 to levels detectable by future TPF-like 5 missions. Thus the oxygen content in the atmosphere of M dwarf planets may not be a reliable biosignature. !

5.47!Poster ! ✩✩✩✩✩Student Trifon Trifonov Zentrum für Astronomie, Heidelberg University, Landessternwarte, Germany Sabine Reffert, & Andreas Quirrenbach Two massive planets around the K giant star eta Ceti We present evidence of a new planetary system around the K giant eta Ceti (HIP 5364, HD 6805, HR 334), based on 118 high precision optical radial velocities taken at Lick observatory since July 2000. Since October 2011, additional 6 near infrared Doppler measurements have been taken using the ESO CRIRES spectrograph (VLT, UT1). The analysis of the two data sets shows that the infrared radial velocities seem to follow the periodic Doppler behavior seen in the optical and thus confirm the planetary hypothesis. Assuming the mass of eta Ceti to be 1.7 solar masses, the best dynamical fit to the data is consistent with two massive planets (m_b sin(i) = 2.55 +/- 0.1 Jup. masses, m_c sin(i) = 3.26 +/- 0.2 Jup masses), with periods of P_b = 407 +/- 2 days, P_c = 740 +/- 4 days, and eccentricities of e_b = 0.11 +/- 0.05, e_c = 0.07 +/- 0.03. These masses and period ratios suggest possible strong interactions between the planets and thus a dynamical test is mandatory. We test a large variety of edge- on coplanar and inclined planetary configurations for stability, which are in good agreement with the derived radial velocities. In total we perform approximately 10000 dynamical integrations with typical time spans of 10^5 years and we summarize them in stability maps. In case stability is achieved we extend the test to at least 10^8 years to see whether the system remain stable in long term period. We found that in the case of a coplanar configuration there are several isolated stable solutions and two well defined stability regions. In certain orbital phase configurations with moderate eccentricities, the planets can be effectively trapped in a stable 2:1 mean motion resonance (MMR), stabilizing the system. A much larger non-resonant stable region exists in low eccentricity parameter space, although it appears to be much further from the best fit than the 2:1 resonant region. In all other cases the system is categorized as unstable or as chaotic. The most important conclusion from the non-coplanar inclined dynamical test is that the planets most likely have nearly circular orbits and are a factor of two more

80 Session 5: Detailed Studies of Known Exoplanets and Exoplanet Systems massive than their suggested minimum masses. Assuming larger inclinations and thus larger planetary masses leads to instability in all cases. This stability constraint of the inclination excludes the brown dwarf mass possibility of the two companions and strongly favors a planetary system.! 5.48!Poster ! ✩✩✩✩✩Student Simon Walker University of Warwick, UK Peter Wheatley, & Richard West Determining the population and evolution of hot Jupiters by quantifying WASP selection effects We have inverted the observed sample of WASP planets to the underlying population of hot Jupiters through a quantitative study of the selection biases in the WASP project. We find a clear pile up in the underlying population with orbital periods between 3 and 5 days, which is not apparent in the Kepler data due to the relatively low number of hot Jupiters detected. The WASP project is ideally suited for this analysis, with a sample of 326,000 bright and well sampled FGK stars, allowing us to discover the largest number of hot Jupiters. Our observed period pile up is a crucial constraint on models of hot Jupiter migration. The dynamical evolution of giant planets is likely to drive the evolution of most planetary systems.!

5.49!Poster Peter Wheatley University of Warwick, UK The Next Generation Transit Survey (NGTS) The Next Generation Transit Survey (NGTS) is a new ground-based sky survey designed to find transiting Neptunes and super-Earths. By covering at least sixteen times the sky area of Kepler we will find small planets around stars that are sufficiently bright for atmospheric characterization with facilities such as JWST, EChO and FINESSE. The bright host stars will also allow radial velocity confirmation and mass determination, providing the first statistical sample of super-Earth densities and bulk compositions. This sample will place key constraints on 5 models of small planet formation and evolution. I will describe the NGTS facility, which is being constructed at the ESO Paranal observatory during 2013, and present data from our prototype instruments as well as the results of quantitative simulations of our planet catch. These show the potential to measure masses and densities of thirty bright super-Earths and over two hundred Neptunes.

! 5.50!Poster Sloane Wiktorowicz UC Santa Cruz, USA & Gregory Laughlin Direct Detection of Spatially Unresolved Exoplanets with Polarimetry The detection of scattered light from exoplanets gives direct access to the structure and composition of their atmospheres. Currently, most spatially unresolved, scattered light experiments focus on nearly edge-on, transiting systems. The temporal changes that occur during planetary occultations are used to suppress systematic errors that would otherwise overwhelm the planetary signal. However, linear polarimetry also has the potential to detect scattered light from exoplanets. This is because the polarization state of light scattered by a planetary atmosphere distinguishes it from both the direct light from the host star and the Wien tail of thermal re-radiation from the planet. Scattered flux should be identifiable regardless of orbital inclination, because both degree and position angle of polarization are modulated continuously throughout the orbit. Orbital inclination, mean number of scattering events, and scattering particle size and index of refraction are discernable with polarimetry. The discovery of spherical droplets of sulfuric acid suspended in the Venusian atmosphere was made with multi-wavelength polarimetry 40 years ago, and technology has matured to the point where such discoveries are now possible around spatially unresolved exoplanets. We will report on the search for scattered light from known exoplanets in B band using the POLISH2 polarimeter on the Lick 3-m telescope. This instrument simultaneously measures all four Stokes parameters (I, Q, U, and V), and it achieves precision within 2.0 times the photon shot noise limit over an entire observing run. The POLISH2 polarimeter is therefore ideally suited for direct detection of spatially unresolved

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exoplanets. This work is supported by a NExScI Sagan Fellowship, UC Lab Fees Research Grant, and UCO/Lick Observatory.!

5.51!Poster Robert Wittenmyer University of New South Wales, Australia Songhu Wang, Jonathan Horner, Chris Tinney, Paul Butler, Hugh Jones, Brad Carter, Graeme Salter, Simon O'Toole, Jeremy Bailey, & Duncan Wright Forever alone? Testing single eccentric planetary systems for multiple companions Determining the orbital eccentricity of an extrasolar planet is critically important for understanding the system's dynamical environment and history. However, eccentricity remains the most poorly-determined orbital element due to irregular sampling of radial-velocity measurements. Some systems previously thought to contain a single, moderate-eccentricity planet have been shown, after further monitoring, to host two planets on nearly-circular orbits. We investigate published apparent single-planet systems to see if the available data can be better fit by two lower-eccentricity planets. We identify nine promising candidate systems and perform detailed dynamical tests to confirm the stability of the potential new multiple-planet systems. Finally, we compare the expected orbits of the single- and double-planet scenarios to better inform future observations of these interesting systems.!

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5.52!Poster! Ji-Wei Xie University of Toronto, Canada & Yanqin Wu Transit Timing Variation of Kepler Planets: Mean Motion Resonance and Multiplicity Transit Timing Variation (TTV) has recently become powerful in characterizing exoplanet systems (Xie 2012, Steffen et al.2013 and the references therein). A sinusoidal TTV is likely an evidence of planets near Mean Motion Resonance (Lithwick et al. 2012). In this work, we first measure the TTV for more than 2700 Kepler planet candidates (Burke et al. 2013).Many (about a few hundred) sinusoidal TTV are identified; some are in multiple transiting systems showing the expected interacting sinusoidal TTV pairs, while some are in single transiting systems with the TTV counter part being missed by Kepler. We then calculate the relative fractions of the sinusoidal TTV in systems with 1, 2, 3 and 4 or more transiting planets and compare them to different theoretical models, which finally shed light on the dynamical features of these thousands of planet candidates. !

82 Session 6: Debris Disks as Signposts of Planetary Systems!

6.01!Invited Review Talk Mark Wyatt Institute of Astronomy, Cambridge University, UK Debris discs as components of extrasolar planetary systems While planets are the most treasured outcome of the planet formation process, they are not the sole components of extrasolar planetary systems. Indeed, it is as common for a star to have a debris disc as it is to be known to have orbiting planets. These debris discs are made up of dust, planetesimals (and in a few cases also gas) which, as the name suggests, can be considered to be the left-over material that failed to form into planets. For a number of reasons, this debris is an important component of exoplanetary systems. From an observational point of view the fact that relatively small quantities of dust (an asteroid's worth) are easily detectable around nearby stars means that this phenomenon can provide unique information on the structure of the underlying planetary system that could not have been discovered using other techniques. For example, the debris likely traces regions of dynamical stability within the planetary system (i.e., it tells us where there are no planets), and its detailed structure can bear signatures of gravitational sculpting that can be used to pinpoint the perturbing planets and even to ascertain their evolutionary history. The existence (or not) of a debris disc, and how that correlates with other aspects of the system, such as the presence of planets, is also a testament to how planet formation processes played out. Moreover, at early stages the debris may have been dynamically relevant to the stability of the planetary system, and may bear witness to ongoing planet formation processes. This talk will give a broad overview of how the study of debris discs has influenced our understanding of exoplanetary systems, both from observational and theoretical perspectives.

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83 Session 6: Debris Disks as Signposts of Planetary Systems!

6.02!Contributed Talk ! ✩✩✩✩✩Student Meredith MacGregor Harvard University, USA A Resolved Millimeter Emission Belt in the AU Mic Debris Disk Imaging debris disks at millimeter wavelengths is important, because emission at these long wavelengths is dominated by large grains with dynamics similar to the population of dust-producing planetesimals. We have used the SMA and ALMA to make 1.3 millimeter observations of the debris disk surrounding the nearby (9.9 pc), ~10 Myr-old, M-type flare star AU Microscopii. We characterize the disk by implementing Monte Carlo Markov Chain methods to fit parametric models to the visibilities. The millimeter observations reveal a belt of dust emission that peaks at a radius of 40 AU. This outer size scale agrees with predictions for a reservoir of planetesimals (a "birth ring") based on the shape of the midplane scattered light profile. We do not find any significant asymmetries in the structure or the centroid position of the emission belt. The ALMA observations with a resolution of 0.6 arcsec (6 AU) also reveal a previously unknown central emission peak, ~6 times brighter than the stellar photosphere at these wavelengths. This central component remains unresolved and could be explained by stellar activity or an inner planetesimal belt located < 3 AU from the star and containing roughly 1% the mass of the outer belt. Future observations with higher angular resolution will be able to distinguish between these possibilities.References:MacGregor, M.A., Wilner, D.J., Rosenfeld, K.A., Andrews, S.M., Matthews, B., Hughes, A.M., Booth, M., Chiang, E., Graham, J.R., Kalas, P., Kennedy, G., Sibthorpe, B., 2013, ApJ, 762, L21Wilner, D.J., Andrews, S.M., MacGregor, M.A., Hughes, A.M., 2012, ApJ, 749, L27!

6.03!Contributed Talk! 6 Kate Su Steward Observatory, University of Arizona, USA Signpost of Multiple Planets in Debris Disks We will review the nearby debris disk structures revealed by multi-wavelength images from Spitzer and Herschel, and complemented with detailed spectral energy distribution modeling. Similar to the definition of habitable zones around stars, debris disk structures should be identified and characterized in terms of dust temperatures rather than physical distances so that the heating power of different spectral type of stars is taken into account and common features in disks can be discussed and compared directly. Common features, such as warm (~150 K) dust belts near the water-frost line and cold (~50 K) Kuiper belt analogs, give rise to our emerging understanding of the levels of order in debris disk structures and illuminate various processes about the formation and evolution of exoplanetary systems. In light of the disk structures in the debris disk twins (Vega and Fomalhaut), and the current limits on the masses of planetary objects, we suggest that the large gap between the warm and cold dust belts is the best signpost for multiple (low-mass) planets beyond the water-frost line.!

84 Session 6: Debris Disks as Signposts of Planetary Systems!

6.04!Contributed Talk! Jean-Charles Augereau Institut de Planétologie et d'Astrophysique de Grenoble, France J. Lebreton, R. van Lieshout, O. Absil, B. Mennesson, M. Kama, C. Dominik, A. Bonsor, H. Beust, D. Defrère, V. Faramaz, P. Hinz, Q. Kral, A.-M. Lagrange, W. Liu, & P. Thébault Detailed model of the exozodiacal disk of Fomalhaut and its origin The star Fomalhaut is famous for its cold debris belt at 140 AU imaged at optical to millimeter wavelengths, and for its potential planet which basic properties and orbital parameters are subject to debate. However, much less is known about the innermost regions of the Fomalhaut planetary system. Direct imaging with Spitzer and Herschel shows clear evidence for an infrared excess arising from within 20 AU radius of the star, but the large beams of these observatories prevent any further conclusion on the actual distribution of the hot and warm dust in the inner few AU.In this talk, we report on our current view of the exozodiacal dust disk of Fomalhaut based on resolved VLTI and Keck Interferometer Nuller observations, complemented by detailed radiative transfer modeling. The interferometric observations in the K- and N-bands reveal tiny - less than 1% - excesses within a field of view of ~5 AU that we attribute to exozodiacal dust. We developed a parametric exozodiacal disk model that incorporates a new treatment of the dust sublimation that accounts for the size-dependent removal timescale of the grains. We use a Bayesian inference method to extract the best fit parameters from a large grid of models.Our model of the Fomalhaut exozodi reproduces the interferometric data and the mid- to far-infrared photometric measurements from Spitzer and Herschel. It consists of two dust components: a hot exozodiacal ring of carbon-rich unbound grains at less than 0.2 AU, and an asteroid belt at about 2 AU that is protected from sublimation and has a larger mass. We propose a possible connection between the two dust populations and we speculate that most of the hot exozodis provide clues for the presence of an underlying population of asteroid belts that can remain otherwise elusive by current observatories. Finally, we will briefly discuss the origin of the dust production activity in the inner regions of Fomalhaut in the light of the new, very eccentric orbit for the imaged planet.!

6.05!Contributed Talk! Jonathan Marshall Universidad Autonoma de Madrid, Spain & the DUNES consortium Final Results of the Herschel Open Time Key Programme DUNES 6 The Herschel Open Time Key Programme Dust around Nearby Stars (DUNES) observed 133 nearby, Sun-like stars searching for evidence of excess emission at far-infrared wavelengths above that expected from the star. Detection of a such cold excesses can be interpreted as presence of circumstellar dust, the by-product of planetesimal formation around these stars, at a similar flux level to that predicted for the Solar systemʼs Edgeworth- Kuiper belt.Having completed the survey, we found an increased dust incidence with Herschel (20.2 ± 2%) compared to previous measurements (~ 12.1 ± 5%). We see no trend in the incidence of excess across the spectral types observed by DUNES, as has previously been reported for A-M stars. Around half of the discs exhibit extended emission, representing a vast improvement in the number of spatially resolved debris discs and thereby the quality of modeling that can be applied to constrain the physical properties of those systems. From an analysis of the debris disc parameters we identified weak trends suggesting a decrease of the mean black body disc radius from F-type to K-type stars, a correlation between the disc extent and stellar age, and an anti-correlation between the disc black body temperature with the stellar age. Some of the discs display peculiar SEDs with spectral indexes in the 70-160 μm range steeper than the Rayleigh-Jeans one, whilst not unheard of, it is typically seen at sub-mm wavelengths. Finally, some stars are associated with faint far-IR excesses attributed to a new class of cold discs. Although it cannot be excluded that these excesses are produced by coincidental alignment of background galaxies, statistical arguments suggest that at least some of them are true debris discs.In this talk we will present the key results of DUNES, beginning with a statistical summary of the whole survey. Specific attention will then be given to particular cases of interest in the survey, e.g. large, bright individual objects, those stars hosting exoplanets and the unusual ʻcold discʼ candidates identified in the survey.!

85 Session 6: Debris Disks as Signposts of Planetary Systems!

6.06!Contributed Talk! Neil Phillips Joint ALMA Observatory / ESO, Chile Bruce Sibthorpe, Grant Kennedy, Brenda Matthews, Jane Greaves, Mark Wyatt, & Wayne Holland Five Stars, Three Debris Discs and a Galaxy: Two Exceptional Debris Disc Systems We present analysis of Herschel, Spitzer and SCUBA-2 observations of two striking debris disc systems discovered during a study of nearby A-type star systems with Spitzer in support of the DEBRIS Herschel Key Programme. The first is a quadruple star system which contains two debris discs, one around the primary A-type star which appears radially truncated by a secondary spectroscopic binary pair, and another around a tertiary G-type star on a very wide orbit. This system is both a nice example of a debris disc shaped by interactions in a multiple star system, and of two co-eval debris discs which likely formed from the same primordial material. The second system is a single late A-type star, with no indicators of youth, which exhibits one of the most massive debris discs within 50 pc of the Sun (dust mass approximately 0.04 Earth masses, similar to the debris disc of beta Pictoris). The disc appears to be almost face-on, potentially making this an excellent candidate for ALMA imaging to determine the structure of the disc and look for interactions between the dust and planets. These systems highlight the benefit of surveys which are unbiased by previous detections, and surveys which consider star systems as a whole.!

6.07 !Poster ! ✩✩✩✩✩Student Nicholas Ballering University of Arizona Steward Observatory, USA George Rieke, Kate Su, & Edward Montiel A Trend Between Cold Debris Disk Temperature and Stellar Type: Implications for the Formation and Evolution of Wide-Orbit Planets Cold debris disks trace the limits of planet formation or migration in the outer regions of planetary systems, and thus have the potential to answer many of the outstanding questions in wide-orbit planet formation and evolution. We characterized 170 cold debris disks in the infrared excess spectral energy distributions of 546 main sequence stars observed by Spitzer IRS and MIPS. We found a trend between the temperature of the inner edges of cold 6 debris disks and the stellar type of the stars they orbit. This argues against the importance of strictly temperature- dependent processes (e.g. ice lines) in setting the dimensions of cold debris disks. Also, we found no evidence that delayed stirring causes the trend. The trend may result from outward planet migration that traces the extent of the primordial protoplanetary disk, or it may result from planet formation that halts at an orbital radius limited by the efficiency of core accretion.!

6.08!Poster ! ✩✩✩✩✩Student Sara Barber University of Oklahoma, USA Adam Patterson, Mukremin Kilic, Sandy Leggett, Patrick Dufour, Joshua Bloom, & Dan Starr The Frequency of Debris Disks at White Dwarfs We present near- and mid-infrared photometry and spectroscopy from PAIRITEL, IRTF, and Spitzer of a metallicity- unbiased sample of 117 cool, hydrogen-atmosphere white dwarfs from the Palomar-Green survey and find five with excess radiation in the infrared, translating to a 4.3% frequency of debris disks. This is slightly higher than, but consistent with the results of previous surveys. Using an initial-final mass relation, we apply this result to the progenitor stars of our sample and conclude that 1 – 7Mʼ stars have at least a 4.3% chance of hosting planets; an indirect probe of the intermediate-mass regime eluding conventional exoplanetary detection methods. Alternatively, we interpret this result as a limit on accretion timescales as a fraction of white dwarf cooling ages; white dwarfs accrete debris from several generations of disks for ~10Myr. The average total mass accreted by these stars ranges from that of 200km asteroids to Ceres-sized objects, indicating that white dwarfs accrete moons and dwarf planets as well as Solar System asteroid analogues.!

86 Session 6: Debris Disks as Signposts of Planetary Systems!

6.09 !Poster Amy Bonsor Institute de Planétologie et d'Astrohphysique de Grenoble, France Grant M. Kennedy, Justin R. Crepp, John A. Johnson,Mark C. Wyatt, Bruce Sibthorpe & Kate Y. L. Su The Population of Debris Discs Orbiting Subgiants (ʻretired' A stars) Whilst debris discs orbiting main-sequence stars are well studied, very little is known regarding their fate when the star evolves onto the giant branch. For intermediate mass (A-type) stars, giants provide a unique opportunity to detect planets using the radial velocity technique, otherwise prohibited by high jitter levels and rotationally broadened lines in main-sequence intermediate mass (A-type) stars. Such stars can provide key insights into the structure of planetary systems around intermediate mass stars. In our Herschel program (PI Bonsor) we searched for the presence of debris discs orbiting a sample of 36 subgiants, half of which have RV detected companions. The aim was to exploit this unique opportunity to study the structure of planetary systems around intermediate mass stars. Our best detection, Kappa Cr B, provides the first resolved images of a debris disc orbiting an evolved star. Kappa Cr B is also orbited by two companions. I will present our constraints on the structure of this planetary system obtained from the Herschel images, alongside detection limits on the orbital parameters of these companions, obtained using further RV monitoring (Keck I HIRES) and AO imaging (Keck II NIRC2). Kappa Cr B is an intriguing example of a planetary system where both planets and dusty debris have been detected and in which interactions between them may be critically important. In addition to this using the detection statistics obtained from our survey we are able to improve our understanding of the evolution of debris discs around intermediate mass stars, complimenting previous studies of the population of debris discs orbiting main-sequence A stars. Whilst our small number statistics make it difficult to make definitive conclusions regarding the correlation between the presence of debris discs and planets, we are able to provide clear evidence that debris discs survive beyond the star's main-sequence evolution. !

6.10!Poster Mark Booth University of Victoria, Canada Grant Kennedy, Bruce Sibthorpe, Brenda Matthews, Mark Wyatt, Gaspard Duchêne, JJ Kavelaars, David 6 Rodriguez, Jane Greaves, Alice Koning, Laura Vican, George Rieke, Kate Su, Amaya Moro-Martín, & Paul Kalas The Place of Debris Discs in Planetary Systems Planetary systems are theoretically expected to contain a combination of planets and debris discs. Debris discs are generally easier to directly detect than planets due to the large total surface area of the dust seen through thermal emission and scattered light. Finding where debris discs are located in a planetary system gives us an indication of where planets might reside and what the history of the system is. While disc properties can be inferred from unresolved photometry alone, there is a degeneracy between disc radius and dust temperature that depends on the grain size distribution and optical properties. The launch of Herschel, with an angular resolution superior to previous far-infrared telescopes, allows us to spatially resolve more discs and locate the dust directly. As part of the Herschel DEBRIS survey, we have fitted the disc radii of 9 resolved discs around A stars assuming a narrow ring model. By comparing this radii to the radii we find by fitting blackbody spectra to the SEDs, we aim to find an improved way of estimating disc radii for unresolved systems. The ratio between the resolved and blackbody radii varies between 1 and 2.5. This ratio is inversely correlated with luminosity and any remaining discrepancies are most likely explained by differences to the minimum size of grain in the size distribution or differences in composition. We find that three of the systems are well fit by a narrow ring, two systems are borderline cases and the other four likely require wider or multiple rings to fully explain the observations, reflecting the diversity of planetary systems.!

87 Session 6: Debris Disks as Signposts of Planetary Systems!

6.11! Poster! Ramiro de la Reza Observatorio Nacional/MTCI, Brazil & Carolina Chavero On the Lifetime of Debris Disks Around A-type Stars How long do the debris disks (DD) around A-type stars last? What is the relation between the DD and Main Sequence (MS) life spans? To try to answer these question we have collected 17 resolved and 23 non-resolved DD around A-type stars. The comparison of their observed flux ratios at 70 μm and 24 μm with those calculated by a collisional model of DD, in function of a homogeneous group of deduced stellar ages, enabled us to estimate the DD lifetimes. The observed points show that DD appear to disappear near the end of the classical MS lifetimes. For the 2 Mo and 3 Mo stellar masses contemplated here, a type of less massive disks appears to exist. Only in the 3 Mo case, these low massive DD indicate somewhat longer lifetimes, lasting up to the end of the corresponding MS lifetime. !

6.12!Poster Robert De Rosa Arizona State University, USA Jennifer Patience, Brent Smith, Christian Marois, Inseok Song, Bruce Macintosh, James Graham, Rene Doyon, & Mike Bessell Exploring the correlation between resolved stellar companions and measured 24um WISE excess around nearby A-type stars We present the results of the Volume-limited A-STar (VAST) survey, the first large-scale adaptive-optics multiplicity survey of over 300 A-type stars within 75pc, designed to measure the population of stellar companions over a separation range of 30 to 1000AU. The presence of a companion star is an important factor that can influence both planet formation and disk stability. By combining the results of the VAST survey with existing all-sky WISE data and archival Spitzer measurements, we can explore the correlation between measured infrared excess at 24um, and the presence of a binary companion within the high-resolution adaptive-optics data. Using a combination of these data we have constructed a sample of A-type stars with measured 24um excess drawn from the VAST survey, and the frequency and properties of the binary companions within this sample is investigated, and compared with that of a representative control sample of non-excess stars. The results of this study will allow for a greater understanding of the interaction between a companion star and a circumstellar debris disk, informing future study into the formation and stability of planetary-mass companions within binary systems, which are relatively common amongst 6 A-type stars.!

6.13!Poster Denis Defrère University of Arizona, USA Phil Hinz, Andrew Skemer, Bertrand Mennesson, Rafael Millan-Gabet, Vanessa Bailey, & Timothy J. Rodigas Searching for faint exozodiacal disks: Keck results and LBTI status The inner solar system, where the terrestrial planets formed and evolve, is populated by small (1-100 Œºm) grains of dust produced by collisions of asteroids and outgassing comets. This dust cloud - the zodiacal cloud, also called debris disk - fills the ecliptic plane within the asteroid belt and can be clearly seen from Earth as a diffuse glow in the night sky. At visible and infrared wavelengths, it is in fact the most luminous component in the solar system after the Sun itself, and the Earth would appear as an embedded clump in it as seen from an external observer. Hence, the possible presence of dust in the habitable zone around nearby main-sequence stars is considered as a major hurdle toward the direct imaging of Earth-like extrasolar planets with future dedicated space-based telescopes. Unfortunately, very little is known about the presence of dust in the terrestrial planet region of nearby planetary systems. So far, debris disks have mostly been observed on relatively large spatial scales, corresponding to material located tens to hundreds of AU from their host star. Whether exozodiacal dust is actually present in observable quantities in these systems has been an important question for several years. Mid-infrared single-dish surveys (e.g., IRAS, ISO, Spitzer, WISE) addressed this issue and reported the detection of warm dust (at ~10Œºm) around a handful of candidates with an occurrence rate lower than 1% for nearby main-sequence stars. These systems are however much brighter than the solar Zodiacal cloud (by a factor of 1000 at least) and this

88 Session 6: Debris Disks as Signposts of Planetary Systems! would clearly be a showstopper for future instruments searching for Earth-like planets orbiting in these particular systems. The occurrence and brightness of exozodiacal dust disks around nearby main-sequence stars needs therefore to be better determined in order to prepare future direct imaging missions.In this context, NASA has funded two ground-based mid-infrared nulling interferometers to combine the large apertures available at the Keck observatory and the Large Binocular Telescope (LBT). The Keck Interferometer Nuller (KIN) was under commissioning during the 2004-2007 period and science observations started in 2008 with three Key Science programs. The last KIN observations were gathered in 2011B. These observations provide unprecedented sensitivity to warm exozodiacal dust around a total of 41 nearby main-sequence single stars observed in the various exozodi programs. The data obtained allow us to carry out a statistical analysis about the occurrence of exozodiacal dust disks and to search for possible correlations between the measured KIN excesses and basic stellar properties or the presence of dust inferred from separate observations.A similar survey will start this year using the Large Binocular Telescope Interferometer (LBTI). The LBTI combines the two 8-m primary mirrors of the LBT for high sensitivity and high contrast imaging of nearby planetary systems. It is specifically design to determine the prevalence and brightness of exozodiacal dust with the sensitivity required to prepare future exoEarth direct imaging missions. It was installed in September 2010 at the LBT and first fringes were obtained one month later. Dual-aperture AO-corrected interferometric fringes were realized in April 2012 and first null measurements in September 2012. Phase and tipt-tilt sensing is performed in the K-band and is currently under commissioning. The survey for exozodiacal dust is named HOSTS (The Hunt for Observable Signatures of Terrestrial Planetary Systems) and will start in 2013 after completion of the commissioning. The instrument status, early results, and survey plans will be summarized.

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6.14!Poster ! ✩✩✩✩✩Student Jack Dobinson University of Bristol, UK Zoe Leinhardt, Nick Teanby, & Sarah Dodson-Robinson Transitional Disks: Inferring the Presence of Planets Young planets are difficult objects to study as they are embedded (at least partially) in their stars accretion disk and the host stars are young and highly active. This makes traditional methods of observation challenging. Current theoretical models are based on data from observations of the start of the process (protoplanetary disks) and the end of the process (debris disks). Transitional disks are a recently discovered class of stellar accretion disk. They are characterised by a flux deficit in the near-infared wavelengths with respect to a classic protoplanetary disk, but 6 otherwise have similar spectral energy distributions. The accepted explanation for this deficit is a lack of hot, optically thick material in the inner disk.The exact origin of the inner hole of a transitional disk is elusive as there are many mechanisms that can remove or hide material in the interior. A tantalising idea is that planets clearing gaps in a transitional disk are responsible. There are suggestions that the cumulative effect of many planets each clearing their own region is the most likely explanation for transitional disks with particularly wide holes (10's of AU). The indirect effects of these planets on the dust distribution can be detected by new technology (ALMA), we propose that this indirect tracer is the best method for the detection of young planetary systems.This work focusses on how a single planet clears a gap in a transitional disk by simulating it's dynamical effects on the disk's planetesimal population. In order to successfully recreate a transitional disk, the dust production of colliding bodies must be treated carefully. Two approaches are taken; post-processing of perfectly merging collisions, and use of a detailed collision model which resolves collisions through the use of an outcome lookup table and direct simulation of collisions. The results show that it is possible for a one Jupiter mass planet to clear it's region not only of planetesimals but also dust, with a small amount remaining at the 1:1 resonance. As the eccentricity of the planet is increased, the planet is less successful at clearing it's orbit. Applying a simple thermal disk model to the results shows the presence of pericentre glow in the eccentric simulations, radiative transfer code is used to obtain SED's of the systems. The synthetic SED's and flux maps are used to compare the simulations with actual data to test if this method creating a transitional disk is viable. Further work will include multiple planets in the simulations and the use of a more efficient collision model to enable higher resolution and/or longer simulations. Analysis of the synthetic flux maps and SED's with instrument response models is also planned to gauge the observability of such systems.!

89 Session 6: Debris Disks as Signposts of Planetary Systems!

6.15!Poster Steve Ertel IPAG Grenoble, France Jean-Charles Augereau, Olivier Absil, Amy Bonsor, Vincent Coudé du Foresto, Denis Defrère, Quentin Kral, Jérémy Lebreton, Jean-Baptiste LeBouquin, & Philippe Thébault An unbiased near-infrared interferometric survey for hot exozodiacal dust Exozodiacal dust (exozodi) is located within the first (few) AU around main sequence stars and is thought to be an analog to our zodiacal dust. However, most systems detected so far present significant differences, i.e., the higher temperature and dust mass (though still optically thin). The dust grains are expected to be ground down to below the blow-out size by collisions and expelled from the system due to radiation pressure on time scales of only a few years. Thus, the dust must be transient or replenished with an extreme efficiency. This illustrates the extreme and unexpected nature of these systems, the origin of which remains enigmatic.Observing such systems remained elusive until near-infrared interferometry recently revealed small (~1%) excess around nearby main sequence stars. Our EXOZODI project is designed to observe a large, statistical sample of 200 stars in order to detect and characterize exozodiacal systems and to investigate their origin and evolution. We spatially disentangle the dust emission from the dominating stellar contribution and to detect it using near-infrared interferometry with VLTI/ PIONIER in the southern and CHARA/FLUOR in the northern hemisphere. In addition to the direct implications of our results for the structure and evolution of planetary systems, they are critical for the feasibility and success of future terrestrial planet search missions using direct imaging.In the context of our survey, ~130 stars have already been observed with unprecedented sensitivity to hot circumstellar excess emission. The data obtained allow us to carry out a statistical analysis by correlating the incidence and abundance of hot dust with the properties of the host systems (e.g., age, spectral type of the host star, the existence of known planets or of a Kuiper Belt like planetesimal population). This strongly constrains the origin and evolution of the dust.Follow-up observations of the detected exozodis are scheduled. These observations will constrain the dust temperature and radial distribution (measuring near-infrared colors and the spectral slopes), and the time variability of the excess (taking time series). In addition to the observational work carried out by our team, detailed modeling studies are performed, studying single systems as well as performing simulations of different scenarios trying to unravel the origin and evolution of the dust.In this talk, I present an overview of our EXOZODI project. I will discuss our observing strategy and present a statistical analysis of the results. The fact that not all exozodis known so far can be connected to a known, cold debris disk analog to our Kuiper Belt is a particularly intriguing result. In addition, I will present an overview of the theoretical and modeling studies done by our group studying the connection between the exozodi phenomenon and the architecture of the planetary/planetesimal system.! 6

6.16!Poster ! ✩✩✩✩✩Student Jeffrey Fung University of Toronto, Canada & Pawel Artymowicz A Disk Instability Induced by Radiation Pressure It has long been known that the dynamical evolution of a dusty disk is heavily influenced by radiation pressure. The formation of disk features such as dust walls or rings is likely aided by it. Furthermore, it is possible for a disk to spontaneously generate non-axisymmetric features in the region where the disk transitions from radially optically thin to thick, i.e. the inner disk edge, purely from the shadowing effect of dust. We consider analytically and numerically models of dusty disks with various level of gas coupling, from dust perfectly coupled to gas, to partially, and completely decoupled. We show that in every case it is possible for the inner edge to become dynamically unstable, and the criterion for instability is mainly dependent on the sharpness of the inner edge. The nonlinear evolution of this instability involves features such as vortices, spiral arms, or even fragmentation. !

90 Session 6: Debris Disks as Signposts of Planetary Systems!

6.17!Poster ! ✩✩✩✩✩Student Stephan Hartmann Institute for Astronomy and Astrophysics Tuebingen, Germany Thorsten Nagel, Thomas Rauch, & Klaus Werner Non-LTE Model Spectra for Gaseous Planetary Debris Disks around White Dwarfs Analyses of ultraviolet and optical spectra of white dwarfs revealed a large number of metal-rich single objects. In the last years, the picture of the white dwarfsʼ atmospheres getting polluted due to the accretion of planetary material, e.g. planetesimals, became quite successful in explaining the observations. While usually the white dwarfsʼ almost homogeneous H- or He-atmospheres are used as a detector for the spectral signatures of the pollution, the debris disks themselves, consisting of cold, dusty material yield only few features to analyze the accreting planetary material.However, about 20% of these dusty disks are connected to an additional gaseous disk of similar radial extent. The hotter gas becomes noticeable through double peaked emission features which provide the unique opportunity to directly analyze the debris material before it is accreted onto the white dwarf.We used our Tübingen Accretion Disk code AcDc, assuming non-LTE conditions, to model the metal-rich gaseous diskʼs spectrum. We investigated the chemical mixture as well as the surface density and effective temperature values and utilized the Ca II infrared triplet at ŒªŒª 8498, 8542, 8662 √Ö to determine the geometry of the disk and its time development.!

6.18!Poster Wayne Holland UK Astronomy Technology Centre, UK Brenda Matthews & Jane Greaves Early results from the SCUBA-2 Observations of Nearby Stars (SONS) survey The SONS survey is targeting 115 nearby stars searching for debris signatures in the form of dust emission at 850 microns. The results from SONS provides direct dust masses that cannot be obtained from shorter wavelengths; adds to the far-IR/submillimetre spectrum to constrain the dust size distribution; can resolve disk structures around the nearest systems and provides evidence of resonant clumps and other features in resolved structures that could be indicative of unseen perturbers, such as planets. At the time of writing (end-March 2013) the survey is two-thirds complete and the detection rate is such that SONS has more than double the number of imaged disks at 850 microns. This talk will provide an update on the initial results, highlighting some of the spectacular new disk images obtained.Presented on behalf of the SONS survey team.! 6

6.19!Poster Meredith Hughes Wesleyan University, USA Angelo Ricarte, Noel Moldvai, Gaspard Duchene, Jonathan Williams, Sean Andrews, David Wilner, Amy Steele, & Eugene Chiang Debris Disk Morphology and the Dynamics of Planetary Systems Millimeter-wavelength observations of debris disks probe large grains that are important for characterizing the dynamics of planetary systems. I will describe several methods by which we are attempting to use debris disk morphology to gain insight into the underlying physical mechanisms shaping disk structure. The presentation will center on recent CARMA and SMA observations that spatially resolve a sample of five debris disks around young Solar analogues. I will present observations of three previously unresolved debris disks (HD 104860, HD 377, HD 8907), and highlight key features of their structure. I will also describe the first resolved observations of thermal emission from the disk around HD 61005 ("The Moth"), revealing a double-peaked structure characteristic of a narrow ring viewed close to edge-on. Comparison of the millimeter and scattered light morphology shows that millimeter grains are predominantly confined to the parent body ring rather than tracing the scattered light "wings", supporting an ISM-interaction scenario as the mechanism driving the swept-back morphology of the scattered light disk. I will also briefly describe the concept behind related ongoing (Cycle 1) ALMA observations, which will spatially resolve the vertical structure of edge-on debris disks to measure the velocity distribution of large dust grains, and thereby "weigh" the total mass of perturbing bodies dynamically stirring the disk.!

91 Session 6: Debris Disks as Signposts of Planetary Systems!

6.20!Poster ! ✩✩✩✩✩Student Alan Jackson University of Cambridge, UK & Mark Wyatt Light from shattered worlds Chaotic growth through giant impacts is widely predicted to be the final stage of terrestrial planet formation. In addition to the final terrestrial planets, giant impact also produce copious quantities of debris. This debris is readily detectable for tens of millions of years after an impact and provides a direct window on terrestrial planet formation, as well as forming an important observational link between planet formation theory and observed planetary populations.!

6.21!Poster Andres Jordan Pontificia Universidad Catolica de Chile, Chile Rafael Brahm, Simon Casassus, Bill Dent, Antonio Hales, Francois Menard, & Jorge Cuadra An ALMA view of the cold debris disk in the multi-planetary system around HR 8799 HR8799 is the only multi-planet system with direct imaging available, and its debris disk is a prime ALMA target to understand how planetary systems form and evolve. In this poster we will present the status of our analysis of recently received Cycle 0 Band 7 ALMA observations of the HR8799 planetary system.!

6.22!Poster ! ✩✩✩✩✩Student Quentin Kral LESIA - OBSPM, France 6 Philippe Thébault, & Sébastien Charnoz The LIDT-DD code: a first self-consistent debris discs model with coupled dynamical and collisional evolution I will present the first attempt at developing a fully self-consistent code coupling dynamics and collisions to study debris discs (Kral, Thébault, Charnoz, 2013). So far, these two crucial mechanisms were studied separately, with N-body and statistical collisional codes respectively, because of stringent computational constraints. In particular, incorporating collisional effects (especially destructive collisions) into an N-body scheme was deemed an impossible task because of the exponential increase of particles it would imply.We present here an alternative approach, based on the LIDT3D code developed by Charnoz et al. (2012) for protoplanetary discs, and strongly upgraded to account for the complexity of debris disc physics (high velocity collisions, radiation-pressure affected orbits, wide range of grains' dynamical behaviour, etc). In this 3D Lagrangian-Eulerian code,grains of a given size at a given location in a disc are grouped into"super-particles" (SPs), whose orbits are tracked with an N-body code and whose mutual collisions are treated using a particle-in-a-box scheme. To handle the complexity of grain dynamics, a sorting procedure, regrouping all SPs into dynamical families, has been implemented. A complex SP reassignment routine, looking for and reallocating all redundant SPs,prevents their number from diverging.Our code has been tested for a set of simplified cases for which we reproduce well-known robust results. LIDT-DD has also been used on a first test case: the violent breakup of a massive planetesimal within a debris disc. I will present some preliminary results for this case, for which we are, for the first time, able to quantify the survival time of the signatures left by such violent transient events. I will conclude by showing a list of all potential applications of this code to debris disc studies.!

92 Session 6: Debris Disks as Signposts of Planetary Systems!

6.23!Poster! Jean-Francois Lestrade Observatoire de Paris, France Etienne Morey, & the DEBRIS team Model for the Populations of Debris Disks around A-type, solar-type and M-dwarf stars - Paucity of disk around M-dwarfs Debris disks have been found primarily around intermediate and solar mass stars (spectral types A-K) but rarely around M-type stars. Radial velocity surveys and KEPLER exoplanet candidates indicate that low-mass planets, and small planets, are more abundant around M-dwarf stars. Finally, the prevalence of debris disks around systems with low-mass planets emerge from recent HERSCHEL observations. We have made an attempt to build a comprehensive model for the populations of debris disks that accomodates these facts.We have built a model for the populations of debris disks around A stars, solar-type star, and M-dwarfs which are constrained using the SPITZER and HERSCHEL surveys. This model is based on the steady state collisional evolution of cold planetesimal belts. It is constrained using the70 micron statistics from several SPITZER surveys and by the statisticsof the DEBRIS HERSCHEL survey. We show how this model can adequatly represent this ensemble of data across stellar spectral types, especially whether or not the paucity of debris disks around M-dwarfs is supported by the model in current surveys.Finally, the model population is used to make predictions for future debris disk observations in the submillimeter.!

6.24!Poster Torsten Löhne Jena University, Germany Carlos Eiroa, Jonathan Marshall, Jean-Charles Augereau, Steve Ertel, & Alexander Krivov HD 207129: Failed Planetesimal Formation? Here, we present an analysis of the HD 207129 debris disc, based on the well-covered spectral energy distribution and Herschel/PACS images obtained in the framework of the DUNES (DUst around NEarby Stars) program. We use an empirical power-law approach to the distribution of dust and we then model the production and removal of dust through collisions direct radiation pressure, and drag forces. The resulting best-fit model contains a few thousandths of an Earth mass in dust, with typical grain sizes significantly above the radiation pressure blowout limit. The radial distribution of dust stretches from well within 100 AU in an unusual, outward-rising slope towards a sharp outer edge at about 160-170 AU. We find the belt's dynamical excitation to be low, meaning very long collisional lifetimes. Drag notably fills the inner gap. Both slow self-stirring and planetary perturbations could potentially have formed and shaped this disc. A collisional cascade that slow can, however, already be sustained 6 without any planetesimals larger than a kilometer.!

6.25!Poster Sarah Maddison Swinburne University, Australia Luca Ricci, Leonardo Testi, David Wilner, John Carpenter, & Chris Wright What debris disks can tell us about planetesimal collision models Dusty disks around nearby main-sequence stars have been known for three decades. These are typically called debris disks because the detected dust is thought to be produced by collisions between unseen km-sized planetesimals leftovers of the planetary formation process.In this work we present new spatially resolved observations of the dust thermal emission at 7 mm from a number of southern debris disks, including Fomalhaut and beta Pic, with the Australia Telescope Compact Array (ATCA). The observations provide the longest wavelength detection of these debris disk to date. We combined our results with literature sub-mm data, and in some cases 3 mm ATCA data, to investigate the spectral index of the dust thermal emission in the sub-millimetre and use this to determine the slope of the power-law grain size distribution, q. We find q values for grains with sizes ~1mm that is consistent with the classical prediction for a collisional cascade at the steady-state. These values cannot be explained by more recent collisional models of planetesimals in which either the velocity distribution of the large bodies or their tensile strength is a strong function of the body size. In the case of Fomalhaut and beta Pic this might be explained by the gravitational stirring expected in the planetesimal belts caused by the massive exoplanets detected close to the debris disks.!

93 Session 6: Debris Disks as Signposts of Planetary Systems!

6.26!Poster! Brenda Matthews NRC - Herzberg, Canada Grant Kennedy, Bruce Sibthorpe, Mark Wyatt, Hannah-Broekhoven Fiene, Travis Barman, Bruce Macintosh, Christian Marois & Ben Zuckerman Resolution of the HR 8799 debris disk in the far-infrared: Results from Herschel The HR 8799 debris disk was detected by IRAS, but the face-on nature of the system means the disk has been difficult to image. The detection of a multi-planetary system around HR 8799 makes the imaging of this debris disk of particular interest. We present hereresolved images of the disk taken with the Herschel Space Observatory's PACS and SPIRE cameras. The disk is clearly resolved in the PACS images, but measurement of the disk size at the longer wavelengths is hindered by the increasingly prominent, presumedly background, molecular cloud. We find evidence for the same multi-component disk as was seen by Spitzer (Su et al. 2009), but we are able to establish the outer bounds of the halo component to be 2000 AU, a 100% increase in size over the outer limit of Spitzer. Even this size measurement is curtailed due the filtering limits on the Herschel data. In addition to size constraints, the data reveal that the HR 8799 is more dominated by small grains than is typical in other debris disks, or that there is a steep size distribution. The resolved data allow us to measure the inclination of the disk very well to be 26 ± 3 degrees. We show models of the disk, which appears azimuthally symmetric, and discuss the implications for the temperature of the belt and halo components, which differ from what was seen with Spitzer.!

6.27!Poster Brian Metzger Columbia University, USA Roman Rafikov, & Konstantin Bochkarev Time-Dependent Models of White Dwarf Debris Disks 6 A growing sample of white dwarfs (WDs) with metal-enriched atmospheres are accompanied by excess infrared emission, indicating that they are encircled by a compact dusty disk of solid debris. Such `WD debris disks' are thought to originate from the tidal disruption of asteroids or other minor bodies, but the precise mechanism(s) responsible for transporting matter to the WD surface remains unclear, especially in those systems with the highest inferred metal accretion rates dM_Z/dt ~ 1e8-1e10 g/s. I will present global time-dependent calculations of the coupled evolution of the gaseous and solid components of WD debris disks. Solids transported inwards (initially due to Poynting-Robertson [PR] drag) sublimate at tens of WD radii, producing a source of gas that accretes onto the WD surface and viscously spreads outwards in radius, where it overlaps with the solid disk. If the aerodynamic coupling between the solids and gaseous disks is sufficiently strong (and/or the gas viscosity sufficiently weak), then gas builds up near the sublimation radius faster than it can viscously spread away. This results in a runaway accretion process, during which the WD accretion rate reaches values orders of magnitude higher than can be achieved by PR drag alone. I will discuss the evolution of WD debris disks across a wide range of physical conditions and present calculations of the predicted distribution of observed accretion rates dM_Z/dt, finding reasonable agreement with the current debris disk sample.

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94 Session 6: Debris Disks as Signposts of Planetary Systems!

6.28!Poster ! ✩✩✩✩✩Student Julien Milli IPAG, France Dimitri Mawet, David Mouillet, Anne-Marie Lagrange, Anthony Boccaletti, Gael Chauvin, & Olivier Absil Angular differential imaging of disks: an insight into the innermost regions areound beta Pictoris with the AGPM coronograph Circumstellar disks are the birthplace of planets, especially the disk inner regions within a few tens of astronomical units. Therefore, imaging disks at that scale helps to constrain the planet formation mechanisms. This requires high-contrast and high-resolution techniques as well as specific data reduction methods.Innovative methods such as ADI (Marois et al 2006), LOCI (Lafrenière et al 2007) and Principal Components Analysis (Soummer et al 2012, Amara et al 2012) were developed to detect and characterize faint companions. They are well suited for imaging point sources. For disks, they are also used to reveal high spatial frequency features (Buenzli et al 2010, Thalmann et al 2011, Lagrange et al 2011) but any extended structure is strongly biased (Milli et al 2012).In this presentation, the current data reduction methods suited for disk imaging will be reviewed with a particular emphasis on the effects they induce on the disk observable properties. This will be illustrated by the astrophysical images of the famous debris disks b Pictoris imaged with VLT/NACO and the newly commissioned AGPM coronograph in the eL' band, emphasizing the best parameter set highlighting the disk. Detection and interpretation of the innermost regions of the b Pictoris disk below 1'' will be presented.

! 6.29!Poster ! ✩✩✩✩✩Student Rahul Patel Stony Brook University, USA & Stanimir Metchev A "WISE" Study to Find Warm Dusty Debris Disks in the Solar Neighborhood We have analyzed the WISE photometry of all Hipparcos main sequence stars within 75 pc and found 184 stars with >95% significant mid-infrared excesses that can attributed to circumstellar dust. The excess emission above the predicted photosphere was detected at either 12 or 22 microns, potentially corresponding to dust spanning the circumstellar snow line. We carefully inspected all excess detections to exclude stars with contaminated or confused photometry by checking the WISE, 2MASS and Hipparcos data flags and by visually inspecting the WISE and 2MASS images. 115 of these stars are new excess detections at these wavelengths: an increase of the total known number of warm debris disks within 75 pc by 36%. Given their proximity to the Sun, these warm disk hosts are some of the most attractive targets for extreme-contrast imaging studies of debris disks and extrasolar planets.! 6

6.30!Poster Marshall Perrin STScI, USA Christine Chen, John Debes, Dean Hines, Tushar Mittal, Margaret Moerchen, Mamadou N'Diaye, Laurent Pueyo, Glenn Schneider, & Rémi Soummer Newly seen debris disks from the NICMOS archive Through a reprocessing of the NICMOS coronagraphic archive using improved PSF subtraction techniques, we have obtained new images of five debris disks that were previously unseen using classical PSF subtractions, as part of our project "Archival Legacy Investigation of Circumstellar Environments" (ALICE; see abstract by Soummer et al., this meeting). These are all robust detections with scattered light disk structures seen consistently at two HST roll angles, and in multiple filters for the two targets for which such data are available. These images enable an initial reconnaissance of disk geometries and structures around these stars. The targets are young nearby FGK stars, with ages derived from known membership in nearby moving groups. We present the new HST NICMOS images plus comprehensive SEDs and Spitzer IRS spectra, summarize observed disk properties such as morphology, surface brightness and colors, and place these systems in context relative to previously imaged debris disks. !

95 Session 6: Debris Disks as Signposts of Planetary Systems!

6.31!Poster! Adam Ritchey University of Washington, USA George Wallerstein, Myra Stone, & Guillermo Gonzalez Abundances in Stars with Debris Disks We present the results of a detailed chemical abundance analysis for a sample of 29 solar-type stars known to exhibit excess infrared emission. Our sample was drawn from the Formation and Evolution of Planetary Systems (FEPS) Spitzer Legacy Program, with the explicit goal of finding evidence that the metallicity enhancement in stars with planets is due to metal-rich infall in the later stages of star and planet formation. We will discuss the results of our abundance analysis of 15 different elements and the nature of the trends with condensation temperature, which allow us to discern whether the stellar atmospheres have been polluted with planetary material.

6.32!Poster Christopher Stark Carnegie DTM, USA Alycia Weinberger, Glenn Schneider, John Debes, Hannah Jang-Condell, & Marc Kuchner Debris Disk Asymmetries: Signs of a Planet or Geometric Projection Effects? The majority of resolved debris disks show structures in the form rings, gaps, and warps. Many of these structures exhibit additional radial and azimuthal asymmetries that have been used to suggest the presence of a perturbing planet. However, the observed geometry of the disk flux does not necessarily reveal true density asymmetries, and is the result of three geometric rotations, an unknown scattering phase function, and unknown disk parameters like the scale height and eccentricity. Are the asymmetries observed in debris disks true density asymmetries possibly caused by perturbing planets, or the result of geometric projection effects? Here we focus on examining the asymmetries of the HD 181327 disk revealed by recent multi-roll HST STIS observations as a part of the GO 12228 program. We provide an improved method to deproject resolved disk images and show how simple combinations of disk orientation and geometry can mimic observed radial and azimuthal asymmetries.!

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6.33!Poster Philippe Thebault Paris Observatory, France modelling planet signatures in debris discs The effect a planet on a debris disc's structure is not restricted to pure dynamical sculpting. Its perturbing presence, when combined to stellar radiation pressure and to collisional activity in the disc, can have complex and possibly counter-intuitive consequences.We explore this issue using the "DyCoSS" numerical code (Thebault, 2012, Thebault et al., 2012), which is able to model the coupled effect of dynamics and destructive collisions in a system at steady state.We find that the steady collisional production of small, radiation-pressure- affected grains can strongly attenuate the spatial signature left by a planet in a disc. While for a head-on seen system an embedded Saturn-mass object could still create a detectable pattern, the edge-on case is more problematic and planet- induced structures should only be detected under very favourable conditions. We also consider the case of a planet exterior to an inner debris ring and show that it cannot efficiently truncate the scattered-light luminosity profile at the ring's outer edge. It might, however, leave observable signatures in the ring itself, such as precessing bright clumps for a planet on a low-eccentricity orbit.We also find that the planet's presence induces a strong spatial segregation of grains as a function of their sizes. We explore to what extent this effect can have consequences when observing the system at different wavelengths.!

96 Session 7: Models of Planetary Formation and Evolution!

7.01!Invited Review Talk Roman Rafikov Princeton University, USA Planet Formation: Latest Constraints and Future Directions Recent numerous discoveries of extrasolar planets by different techniques as well as advances in their characterization have provided us with a wealth of new information relevant for understanding planet formation. I will review the main ideas regarding the formation of terrestrial and giant planets in the context of new constraints that emerge regarding both the orbital architectures and physical properties of extrasolar planets. I will also describe some key issues and promising directions that theories of planet formation will need to address in the future.

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97 Session 7: Models of Planetary Formation and Evolution

7.02 !Contributed Talk ! ✩✩✩✩✩Student Michiel Lambrechts Lund University, Sweden & Anders Johansen Rapid growth of giant planet cores by pebble accretion The lifetime of the circumstellar gas disc around a young star is estimated to be on the order of a few Myr. This places a strong constraint on the formation scenarios of the giant planets. In the core accretion paradigm, forming the cores of the ice and gas giant planets by collisions with km-sized planetesimals is not feasible at distances beyond approximately 10 AU within this time constraint. We study numerically the accretion of approximately cm- sized pebbles, loosely coupled to the gas, onto various embryo core masses. The core growth time-scale is shortened by a factor 30-1,000 at 5 AU and by a factor 100-10,000 at 50 AU, compared to the gravitationally focused accretion of, respectively, planetesimal fragments that settled to the midplane or standard km-sized planetesimals. I will also discuss some of the implications of rapid pebble accretion on the attraction of a gaseous envelope and the formation of giant planets.!

7.03 !Contributed Talk ! ✩✩✩✩✩Student Ana-Maria Piso Harvard University, USA Andrew Youdin, & Ruth Murray-Clay On the Minimum Core Mass for Giant Planet Formation The core accretion model proposes that giant planets form by the accretion of gas onto a solid protoplanetary core. Previous studies have found that there exists a “critical core mass" past which hydrostatic solutions can no longer be found and unstable atmosphere collapse occurs. In standard calculations of the critical core mass, planetesimal accretion deposits enough heat to alter the luminosity of the atmosphere, increasing the core mass required for the atmosphere to collapse. In this study we consider the extreme case in which planetesimal accretion is negligible and Kelvin-Helmholtz contraction dominates the luminosity evolution of the planet. We develop a two-layer atmosphere model with an inner convective region and an outer radiative zone that matches onto the 7 protoplanetary disk, and we determine the minimum core mass for a giant planet to form within the typical disk life timescale for a variety of disk conditions, which we denote as “critical core mass". We find that the absolute minimum core mass required to nucleate atmosphere collapse within the disk lifetime is smaller for planets forming further away from their host stars. Moreover, the critical core mass is strongly dependent on disk temperature, opacity and mean molecular weight of the gas. Our results yield lower mass cores than corresponding studies for large planetesimal accretion rates. We therefore show that it is easier to form a planet by growing the core first, then accreting a massive gaseous envelope, rather than forming the core and atmosphere simultaneously.!

98 Session 7: Models of Planetary Formation and Evolution!

7.04!Contributed Talk! Ralph Pudritz McMaster University, Canada & Yasuhiro Hasegawa Planet Formation and Evolution in Traps: Origins of the Mass-Period Relation The mass-period diagram for exoplanets provides important constraints on theories of planet formation and evolution. This diagram is populated by at least three distinct planetary populations: "hot Jupiters" at small orbital radii, more massive Jovian planets gathered at about 1 AU, and a rapidly increasing population of SuperEarths at short periods. Traditional population synthesis models provide important but still incomplete insights as to how these arise. Our work shows that low mass and rapidly migrating planetary cores get trapped at disk inhomogeneities, where strong density or thermal gradients exist (namely, dead zone boundaries, ice lines, and disk heating transition regions). Planet growth and movement occur at rates dictated by the column densities of materials at these traps, and the slow radial inward motion of the traps due to falling disk accretion rates during disk evolution. By combining the theory of traps in evolving disks with standard ideas about how protoplanets accrete - we develop a simple combined picture of how planets evolve in mass- period diagram. Our models compare well with the observations, and account for both the planetary "pile-up" at 1AU, as well as for the origin of SuperEarths and hot Jupiters.!

7.05!Contributed Talk! Hilke Schlichting UCLA, USA Cesar Fuentes, & David Trilling Shedding light onto the Building blocks of Planets: Solar System constraints on the initial Planetesimal Sizes Planetesimals are the building blocks of planets. Although we have a fairly good idea of how the growth of planets proceeds by the accretion of planetesimals, the exact formation mechanism and initial sizes of the planetesimals themselves is less certain. We investigate the growth and subsequent collisional evolution of planetesimals and protoplanets in the outer solar system and compare our results with the size distribution of objects in the Kuiper Belt, which is a remnant from the early solar system and provides valuable constraints for theories of planet formation and collisional evolution. We show, by comparing observations with theoretical models, that the observed Kuiper Belt size distribution is well matched by coagulation models of runaway growth, which start from an initial planetesimal population with radii of about 1 km, and subsequent collisional evolution. The runaway growth phase 7 leaves most of the initial mass in small planetesimals, while only a small fraction of the total mass is converted into large protoplanets. We find that this excess mass in small planetesimals leaves a permanent signature in the size distribution of small bodies that is not erased after 4.5 Gyrs of collisional evolution. Observations of the small KBO size distribution can therefore test if large KBOs grew as a result of runaway growth and constrain the initial planetesimal sizes. We will show that results from recent KBO occultation surveys and the observed KBO size distribution can be best matched by an initial planetesimal population with km-sized planetesimals and that we cannot match the observed KBO size distribution if most of the planetesimal mass was contained in bodies that were 10 km in radius or larger, because their resulting size distribution cannot be sufficiently depleted over 4.5 Gyrs to match observations. !

99 Session 7: Models of Planetary Formation and Evolution

7.06!Contributed Talk ! ✩✩✩✩✩Student Christophe Cossou Astrophysical Laboratory of Bordeaux, France Sean N. Raymond, & Arnaud Pierens A possible origin of compact systems of hot Super Earths Earth-mass planets embedded in gaseous protoplanetary disks undergo Type I orbital migration, which can be directed either inward or outward depending on the local disk properties. Special locations exist in the disk toward which planets migrate in a convergent way (Convergence Zones). However, we show that planets do not systematically converge in convergence zones. Rather, they become trapped in chains of mean motion resonances (MMRs). This causes the planets' eccentricities to increase to high enough values to affect the structure of the horseshoe region and weaken the positive corotation torque. The zero-torque equilibrium point of the resonant chain of planets is shifted inward and the planets migrate interior to the Convergence Zone. We show that compact systems of hot Super Earths are a natural outcome of this process. In a disk with an artificial convergence zone at 3 AU, cohorts of resonant planets systematically migrate to the inner edge of the disk whenever there are more than 10 embryos in the disk. In more realistic disks systems of hot Super Earths are also naturally produced, although the evolution can be more complicated. In addition, more distant planets often survive, perhaps representing giant planet cores or terrestrial planets. Finally, we discuss which disks form giant planet cores at a few AU rather than hot Super Earths. !

7.07!Contributed Talk! Rudolf Dvorak University of Vienna, Austria & Thomas I. Maindl Collision parameters governing water delivery and water loss in early planetary systems We investigate the distribution of parameters describing collisions and impacts in the habitable zone of early planetary systems by numerically simulating a ring of 10,000 planetesimals between 0.9 and 1.1 AU from the central star. This configuration is perturbed by a gas giant whose orbit lies entirely outside the planetesimalsʼ orbits. 7 The simulations are using the full n-body gravitational model to study the detailed properties of each close encounter. While we choose the same mass for each planetesimal (approx. 2.7 lunar masses) in the n-body simulation, we can study collisions of bodies of arbitrary mass ratio because during a close encounter the typical distance of the two bodies is at least one order of magnitude smaller than the corresponding Hill radius. For different assumptions regarding mass ratio and water content of the colliding bodies we derive distributions of impact velocities and impact angles. These results will be used to model impact events of asteroid- to moon-sized objects to study what happens to the water content of such bodies during and immediately after the collision.!

100 Session 7: Models of Planetary Formation and Evolution!

7.08!Poster Kevin Baillie Université Paris Diderot - Paris 7, France & Sebastien Charnoz Protoplanetary disk characteristics as a function of the host star Based on a self-consistent coupling between protoplanetary disk thermodynamics, geometry and dynamics, we designed a 1D-hydrodynamical numerical model for the spreading of the disks as a function of the star characteristics (Baillié et al., 2013 submitted to Astrophysical Journal). We found that the evolution timescale increases for more massive or for steeper surface density disks, and decreases for more massive stars or lower turbulent viscosity parameters. Thus it would be possible to constrain the turbulent viscosity and initial surface density from the star characteristics. In order to do so, we revisit the Isella et al., 2009 observations in the Taurus region stars and the Andrews et al., 2009, 2010 observations of the Ophiuchus stars in order to constrain the initial conditions. Those results will be presented. It is found in particular that there is a strong dependency of the mass accretion rate versus the disk mass and a weaker dependency versus the star mass. Coupled with observed similar conclusions, we derived that the disk mass is scaling as M*^1.5. !

7.09!Poster Ludmila Carone KU Leuven, Centre for mathematical Plasma Astrophysics, Netherlands Rony Keppens, & Leen Decin Weather on strange new worlds: Large scale atmospheric dynamics on tidally locked Earth-like planets in the habitable zone of an M dwarf star It is likely that the first habitable extrasolar planet will be discovered around an M dwarf star. Such a planet will probably be tidally locked: that is, it will face its host star always with one side while the other side will be cast into perpetual darkness. This is in marked contrast to the situation encountered on Earth, where the annual mean insolation results in an axisymmetric thermal forcing with respect to the equator. The closest analogue of a tidally locked terrestrial planet in our Solar System may be the slowly rotating planets Venus and Titan.To explore the dynamics of the atmosphere of a tidally locked planet with Earth-like atmosphere, a parameter study with an idealized global dry circulation model (GCM) was performed using simplified thermal forcing: Different temperature differences between the sub-stellar and anti-stellar point, rotation periods, time scales for radiation, and Rayleigh friction time scales between the surface and the lower atmosphere were investigated. The results show that - provided the temperatures are moderate enough for liquid water - the substellar point should be a possible place for life to evolve: It is associated with an uprising direct circulation-branch, which triggers cloud formation in the presence of water vapor. Furthermore, it will be discussed how observations of transiting terrestrial exoplanets may confirm large scale atmospheric features that are predicted from our model.!

7.10!Poster 7 Sebastien Charnoz Université Paris Diderot / CEA Saclay, France The vertical distritbution of dust in protoplanetary disk : self-consistent simulation and links with observations The observable properties of protoplanetary disks (ppdisks) are mostly governed by their dusty content however it represents a tiny fraction of their mass. Whereas short wavelengths (IR) can probe the upper parts (photosphere) of the ppdisks, long wavelength may probe the disk's midplane. However, most studies assume strong vertical mixing, and the link between the dust content in the disk's midplane and the disk's photosphere is still poorly understood because of the complex coupling of turbulence, coagulation and fragmentation. We will investigate the coupling of these 3 processes with new numerical tools (Charnoz et al., 2011, Charnoz & Taillifet 2012) taking into account coagulation and fragmentation and turbulence in 3D. Disks with and without dead-zones will be considered. We will show that the dusty content of the photosphere is a poor indicator of the midplane content and simple power law extrapolations give poor estimates of the total dust content. The effect of deadzones on the vertical distribution of dust will be also described, and the observational signature of these zones will be presented. Last, we will show how the alpha turbulent parameter may be constrained from the disk's dusty content.!

101 Session 7: Models of Planetary Formation and Evolution

7.11! Poster ! ✩✩✩✩✩Student Jack O'Malley-James University of St Andrews, UK Jane Greaves, John Raven, & Charles Cockell Swansong Biospheres: the biosignatures of inhabited earth-like planets nearing the end of their habitable lifetimes As an inhabited planet evolves alongside its host starʼs main sequence evolution, environmental conditions on that planet change, altering the nature and distribution of life. This affects the remotely detectable biosignatures exhibited by the planet. The biosignature evolution of habitable planets nearing the end of their habitable lifetimes was explored by applying a simple, latitude-based climate model to the present-day Earth. This incorporated orbital parameter variations to provide a guide to surface temperature evolution over the next 3 Gyr. Over time, conditions increasingly favour the survival of simple, microbial organisms. Refuge environments for life were investigated, with results suggesting that in high-latitude regions, microbial life could persist for up to 2.8 Gyr from present. The biosignatures associated with these refuge biospheres were evaluated, beginning to answer the question of how the habitability of Earth (and, by extension, Earth-like planets) will evolve at local scales.!

7.12!Poster ! ✩✩✩✩✩Student Cristobal Petrovich Princeton University, USA Renu Malhotra, & Scott Tremaine In-situ planet formation: implications for the orbital distribution around resonances The multiple-planet systems discovered by the Kepler mission exhibit the following feature: planet pairs near first- order mean-motion resonances prefer orbits just outside the nominal resonance, while avoiding those just inside the resonance. We explore an extremely simple dynamical model for planet formation, in which planets grow in mass at a prescribed rate without orbital migration or dissipation. We develop an analytic version of this model for two-planet systems in two limiting cases: the planet mass grows quickly or slowly relative to the characteristic resonant libration time. In both cases the distribution of systems in period ratio develops a characteristic asymmetric peak-trough structure around the resonance, qualitatively similar to that observed in the Kepler sample. We verify this result with numerical integrations of the three-body problem. We show that for the 3:2 resonance, where the observed peak-trough structure is strongest, our simple model is consistent with the observations for a range of mean planet masses 20-100M⊕. This predicted mass range is higher—by at least a factor of three—than the range expected from the few Kepler planets with measured masses, but part of this discrepancy could be due to oversimplifications in the dynamical model or uncertainties in the planetary mass-radius relation.

7.13!Poster Emily Rauscher Princeton University, USA 7 & Adam Showman Uneven cooling: the influence of atmospheric dynamics on the thermal evolution of gas giants Planets cool and contract as they age, and the cooling rate is dependent on the efficiency with which they can transport heat out to space, first through the convective interior and then radiatively out through the atmosphere. The bottleneck for this cooling is at the radiative-convective boundary (RCB), where the heat transport is the least efficient. Due to differential heating and atmospheric dynamics, the depth of the RCB can vary with latitude and longitude, meaning that the actual global cooling rate may be different from what would be calculated assuming a spherically symmetric RCB, as in 1D evolutionary models. Here we present models of the deep atmosphere of a generic hot Jupiter, calculate the level of inhomogeneity that dynamics can induce in the RCB, and determine the resulting effect on the global thermal evolution. We explore how the strength of this effect changes as a function of planetary parameters and age. Although this issue can apply to any differentially heated gas giant, we focus on the hot Jupiter class of planet because: 1) the thick radiative zones above their deep RCBs can have a stronger influence on deforming the surface of the RCB than would generally be the case for a less-irradiated planet, and 2) an uneven RCB should generally increase the cooling rate, potentially exacerbating the mismatch between the large radii measured for some hot Jupiters and the smaller radii expected from evolutionary models.

102 Session 7: Models of Planetary Formation and Evolution!

7.14!Poster ! ✩✩✩✩✩Student Francoise Remus CEA/DSM/IRFU/SAp, France Stephane Mathis, Jean-Paul Zahn, & Valery Lainey Tidal models: from planetary internal structure to planetary systems formation and evolution Once a planetary system is formed, its fate is determined by the initial conditions and the mass ratio of the planet to its hosting star. Through tidal interaction between components, the system evolves either to a stable state of minimum energy (where all spins are aligned, the orbits are circular, and the rotation of each body is synchronized with the orbital motion) or the companion tends to spiral into the parent body. The rate at which this evolution operates depends on the intensity of the tidal dissipation, which is closely linked to the induced internal frictions, and therefore on the internal structure of the planet. By converting kinetic energy into heat by means of internal friction, tidal interactions modify the orbital and rotational properties of the components of the considered system, and thus their structure through internal heating. Studies have been carried out on the tidal effects in fluid bodies such as stars and envelopes of giant planets. However, the planetary solid regions, such as the mantles of Earth-like planets or the rocky cores of giant planets, when present, may also contribute to tidal dissipation. Therefore, modeling this kind of interaction presents a high interest to provide constraints on planets interiors, whose properties are still quite uncertain. Conversely, if planetary internal structure is known, tidal dissipation modeling will provide constraints on the initial conditions of planetary systems evolution, and thus on their formation.In this talk, we present the tidal dissipation in a planet that possesses an an elastic core consisting of a mix of ice and rock, surrounded by a fluid envelope, such as an ocean. The planet is part of a binary system where what we call the companion (or perturber) may be either the hosting star or a satellite of the planet. Owing to the tide exerted by the companion, the core of the two-layer planet is deformed elastically, but because of the anelasticity of the material composing the core, this deformation is accompanied by a viscous dissipation that we evaluate for every rheology. We first present the different Love numbers that describe its deformation. We then discuss how the quality factor Q depends on the chosen anelastic model and the size of the core. Taking plausible values for the anelastic parameters, and discussing the frequency-dependence of the solid dissipation, we show how this mechanism may compete with the dissipation in fluid layers, when applied to Jupiter- and Saturn-like planets. Recent observations of the Jovian and Saturnian systems have led to new results that show a higher tidal dissipation than expected by the existing models based on scenarios of evolution. Assuming "realistic values" for the rhelological and structural parameters of these planets, our model is able to explain the observed values of tidal dissipation. According to a recent model of Saturnian system formation and evolution (where satellites are formed in the disk), such a high tidal dissipation is required by the satellites to migrate up to their present location.Therefore, when such observational determinations of tidal dissipation are not available, models of planetary systems formation are needed to constrain tidal models and thus planetary systems evolution. Inversely, if tidal dissipation is known, it represents a strong criterion to discriminate one model of planetary system formation to an other.

! 7.15!Poster ! ✩✩✩✩✩Student Katrin Ros Lund University, Sweden & Anders Johansen 7 Ice condensation as a planet formation mechanism Centimeter-sized pebbles are observed in protoplanetary discs, and are a crucial step towards forming planetesimals and planets. However, understanding their formation is difficult, as particles larger than millimeters tend to fragment or bounce, instead of sticking, when they collide.We model particle growth via condensation close to the water ice line around 3 AU, and find that ice condensation is an efficient growth mechanism, capable of forming centimeter-sized to decimeter-sized pebbles on a timescale of 1000 orbits. Water vapour and small ice particles are coupled to the turbulent gas via drag forces, and move in a turbulent diffusion. As an ice particle moves into the hotter region close to the central star it sublimates.The resulting vapour diffuses back across the ice line and condenses onto already existing particles. This redistribution of mass leads toa net growth of ice particles. We model turbulent diffusion by a random walk, and the processes of sublimation and condensation by a Monte Carlo approach. In this model we have so far ignored collisions and materials other than water ice. Instead we focus on isolating the effects of condensation and sublimation on particle growth. We conclude that ice condensation is an important mechanism that should be taken into account in future, more detailed, models of dust growth in protoplanetary discs.!

103 Session 7: Models of Planetary Formation and Evolution

7.16!Poster Andrew Shannon University of Cambridge, UK Yanqin Wu, & Yoram Lithwick Collisional growth of planetesimals:Formation of the Cold Classical Kuiper belt Traditional models of planetesimal growth begin with kilometre sized bodies, which grow by pairwise collisions. Gravitational focussing causes the larger bodies to grow faster than the smaller bodies, and the largest few bodies quickly run away from the rest of the population. As a result, larger planetesimals (100~1000 km) form with low (~0.1%) efficiency (e.g. Kenyon & Luu 1998, Schlichting & Sari 2011). Historically, this low efficiency has been regarded as favourable, as the present day masses of the asteroid and Kuiper belts are similarly lower than the expectations from the minimum mass solar nebula.However, a number of recent results have come into conflict with this model. A massive primordial Kuiper belt would have disrupted long period binaries, which are observed to be abundant (Parker et al. 2011, 2012). In the presence of a massive primordial Kuiper belt, simulations find Neptune migrates to the outer edge of such a belt (Thommes et al. 1999, Gomes et al. 2004), yet Neptune stopped at 30 AU. Combined with these observations suggesting the Kuiper belt could not have been much more massive in the past than it is today, modelling of bright extrasolar debris disks suggests they contain roughly ten Earth masses in large planetesimals, necessary to continuously supply such a large quantity of dust for a few Gyrs (Shannon & Wu, 2011). This would imply implausibly high initial masses if they formed with low efficiency. We revisit growth starting with kilometre sized bodies, and show it always produces this low efficiency. We consider an alternative case, where planetesimals grow by accreting very small (cm) objects, and show that collisional cooling among these small grains changes the character of growth, allowing it to proceed with high efficiency, satisfying the observational demands of the Kuiper belt and of extrasolar debris disks.!

7.17!Poster Craig Stark University of St Andrews, UK Declan A. Diver, Christiane Helling, & Paul B Rimmer The influence of Alfvén Ionization on exoplanetary atmospheres Observations of continuous radio and sporadic X-ray emission from exoplanets and substellar objects suggest that such objects harbour atmospheric magnetized plasmas. This presents a powerful diagnostic tool, allowing us to characterize the local atmospheric environment if the nature of the source plasma and the plasma processes underpinning the emission can be identified. However, for low-mass objects such as brown dwarfs or exoplanets, the degree of thermal ionization is insufficient to qualify the ionized component as a plasma, posing the question: what ionization processes 7 can efficiently produce the required plasma? We propose Alfvén ionization as a simple mechanism for producing localized pockets of ionized gas in the atmosphere, having sufficiently large degrees of ionization (>10^(-7)) that they constitute plasmas. We carefully outline the criteria required for Alfvén ionization to occur and justify its applicability in the atmospheres of exoplanets and brown dwarfs. We find that Alfvén ionization is optimum at mid to low atmospheric pressures where the seed plasma is easier to magnetize and the pressure gradients required to drive the required neutral flows are the smallest. For the model atmospheres considered here, our results show that degrees of ionization ranging from 10^(-6) to as large as 1 can be obtained depending on the atomic and molecular species that are ionized. Furthermore, Alfvén ionization alters the atmospheric chemistry via the creation of new ionic species not normally available in current, thermally-driven atmospheric models. The presence of atmospheric plasmas opens the door to a multitude of plasma processes and radiation emission mechanisms that contribute to the observed radiation signature. We explore the observable consequences of Alfvén ionization, with the hope of identifying useful diagnostics to probe and characterize the nature of exoplanetary atmospheres, such as the magnetic field strength, the electron number density and the chemical composition. !

104 Session 7: Models of Planetary Formation and Evolution!

7.18!Poster ! ✩✩✩✩✩Student Anjali Tripathi Harvard-Smithsonian Center for Astrophysics, USA Kaitlin Kratter, Mark Krumholz, & Ruth Murray-Clay 3D Simulations of Photoevaporative Mass Loss From Hot Jupiters Planetary winds of atmospheric hydrogen escaping from hot Jupiters have been observed in Lyman-alpha for several transiting systems. To characterize this outflow and understand these observations, we develop a global, three-dimensional simulation of atmospheric escape. We self-consistently treat the planetary wind's production by stellar UV heating and its interaction with the stellar wind from the host star. Using the Athena code for hydrodynamics, we model the planet as a static potential at the center of a three-dimensional Cartesian grid, co- rotating with the planet's orbit. We incorporate the stellar wind and incident UV flux as boundary conditions. We introduce photoionization through a planar source of UV flux and include heating and cooling. By running the simulation for several orbital periods (roughly a few days), we are able to study the structure and evolution of the hot Jupiter's planetary wind. Preliminary results of this work will be presented.!

7.19!Poster Xiaojia Zhang UC Santa Cruz, USA Beibei Liu, Douglas N. C. Lin, Sverre J. Aarseth, & Clement Baruteau Growth and Retention of Multiple Embryos in Evolving Protostellar Disks Based on core accretion model of planetary formation, the current theory still has difficulties to explain the formation of gas giants within a typical gas disk lifetime. However nearly 15 – 20% of solar type stars harbour at least one gas giant planet. The probability of finding additional gas giants around stars with known gas giants is nearly 60%. Here we provide a comprehensive scenario to shorter the time scale for gas giantsʼ formation and the retention of planet cores from the fast type I migration. By using a self-consist disk structure, the surface density and temperature gradient are dependent on local heating mechanism. In an disk of inner viscous heating and outer irradiation heating mechanism, the embryos with about 10M⊕ could undergo outward migration in the viscous 7 heating region since the disk is shallowed in this part. The different directions of Type I migration then make the embryos trapped in the transiting region of the two different heating mechanism. After the embryos gathered, strong gravitational perturbation may enhance the merging and scattering rate of them and increase the coresʼ mass in a relative short time scale.!

105 Session 8: Evolution of Planetary Systems

8.01!Invited Review Talk Rosemary Mardling Monash University, Australia Evolution of Planetary Systems I will give an overview of our current understanding of the secular and dynamical evolution of planetary systems including the role of dissipation via disks and tides, and the challenges provided by observational constraints.

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106 Session 8: Evolution of Planetary Systems!

8.02 !Contributed Talk ! ✩✩✩✩✩Student Rebekah Dawson Harvard-Smithsonian Center for Astrophysics, USA Ruth A. Murray-Clay, & John Asher Johnson Constraining planetary migration mechanisms in systems of giant planets It was once widely believed that planets formed peacefully in situ in their proto-planetary disks and subsequently remain in place. Instead, growing evidence suggests that many giant planets undergo dynamical rearrangement that results in planets migrating inward in the disk, far from their birthplaces. However, it remains debated whether this migration is caused by smooth planet-disk interactions or violent multi-body interactions. Both classes of model can produce Jupiter-mass planets orbiting within 0.1 AU of their host stars, also known as hot Jupiters. In the latter class of model, another planet or star in the system perturbs the Jupiter onto a highly eccentric orbit, which tidal dissipation subsequently shrinks and circularizes during close passages to the star. We assess the prevalence of smooth vs. violent migration through two studies. First, motivated by the predictions of Socrates et al. (2012), we search for super-eccentric hot Jupiter progenitors by using the "photoeccentric effect" to measure the eccentricities of Kepler giant planet candidates from their transit light curves. We find a significant lack of super- eccentric proto-hot Jupiters compared to the number expected, allowing us to place an upper limit on the fraction of hot Jupiters created by stellar binaries. Second, if both planet-disk and multi-body interactions commonly cause giant planet migration, physical properties of the proto-planetary environment may determine which is triggered. We identify three trends in which giant planets orbiting metal rich stars show signatures of planet-planet interactions: (1) gas giants orbiting within 1 AU of metal-rich stars have a range of eccentricities, whereas those orbiting metal- poor stars are restricted to lower eccentricities; (2) metal-rich stars host most eccentric proto-hot Jupiters undergoing tidal circularization; and (3) the pile-up of short-period giant planets, missing in the Kepler sample, is a feature of metal-rich stars and is largely recovered for giants orbiting metal-rich Kepler host stars. These two studies suggest that both disk migration and planet-planet interactions may be widespread, with the latter occurring primarily in metal-rich planetary systems where multiple giant planets can form. Funded by NSF-GRFP DGE-1144152.!

8.03!Contributed Talk! Adam Kraus Harvard-Smithsonian CfA, USA & Michael Ireland The Impact of Stellar Multiplicity on Planetary Systems The majority of searches for extrasolar planets have concentrated exclusively on single stars, actively avoiding close binary systems where the companion might complicate the observations and data analysis. However, the majority of solar-type stars are found in binary systems. These binary companions should exert a strong dynamical influence on any planetary system, and hence this systematic bias leaves out knowledge of planet formation fundamentally incomplete. We will present the results of a high-resolution imaging survey to identify binary companions among a volume-limited sample of 100 Kepler planet hosts within 250 parsecs. This survey exploits nonredundant aperture-mask interferometry (NRM) to super-resolve binary companions down to 1/4 of the 8 diffraction limit (15 mas; <5 AU), identifying the dynamically significant binary companions that are missed by standard imaging surveys. Our results show that binarity does indeed have a profound influence on planet occurrence, suppressing the planet frequency by a factor of ~4 in 5-50 AU binaries. However, unexpected trends for planet survival also are starting to emerge.!

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8.04!Contributed Talk! Yanqin Wu University of Toronto, Canada Yoram Lithwick, & Ji-Wei Xie Orbital structure of Kepler Planetary Systems The Kepler planetary transit mission returns data on thousands of planet candidates, in terms of their sizes, orbital periods and multiplicities. To infer the intrinsic properties of the planetary systems, we look at a variety of indexes (transit-timing variations, period distributions, period ratio distributions, etc.) and arrive at the following conclusions. We find that Kepler systems can include both dynamically cold (coplanar, tightly packed) and dynamically hot (highly non-coplanar, and sparsely spaced) varieties. The relative fractions and the detailed specification for each variety are well constrained by Kepler's transit observations.We discuss the evolution of planetary systems, in light of these discoveries. !

8.05!Contributed Talk! Jay Farihi University of Cambridge, UK Amy Bonsor, Boris Gänsicke, Jane Greaves, Detlev Koester, Olja Panic, & Mark Wyatt Archaeology of Exo-Terrestrial Planetary Systems We now stand firmly in the era of solid exoplanet detection via Kepler and other state of the art facilities. Yet the empirical characterization of these most intriguing planets is extremely challenging. Transit plus radial velocity data can yield planet mass and radius, and hence planet density, but the bulk composition remains degenerate and model–dependent. The abundances of a handful of exoplanet atmospheres can be estimated from transit spectroscopy, but probing only the tenuous outer layers of those planets. Fortunately, as demonstrated by Spitzer and complementary ground–based observations, debris disk–polluted white dwarfs can yield highly accurate information on the mass and chemical structure of rocky minor planets (i.e. exo–asteroids), the building blocks of solid exoplanets. The white dwarf distills the planetary fragments, and provides powerful insight into elemental composition of the parent body. This archaeological method provides empirical data on the assembly and chemistry of exo-terrestrial planets that is unavailable for any planetary system orbiting a main–sequence star. In the Solar System, the asteroids (or minor planets) are leftover building blocks of the terrestrial planets, and we obtain their compositions -- and hence that of the terrestrial planets -- by studying meteorites. Similarly, one can infer the composition of exo-terrestrial planets by studying tidally destroyed and accreted asteroids at polluted white dwarfs. I will present ongoing, state of the art results using this unconventional technique, including ALMA Cycle 0 data and the lasting impact of infrared space missions like Spitzer. Some highlights will include the recent detection of terrestrial-like debris in the Hyades star cluster, as well as the detection of a few water-rich planetesimals that may represent the building blocks of habitable exoplanets.!

8.06!Contributed Talk ! ✩✩✩✩✩Student Brett Addison University of New South Wales, Australia Chris Tinney, & Duncan Wright Recently Discovered Exoplanetary System in Spin-Orbit Misalignment from Rossiter-McLauglin Measurements Over 800 extrasolar planets have been discovered over the past two decades at an ever-increasing pace. In addition to finding new planets, a detailed analysis of their structure, composition, and other bulk properties is needed in order to understand the processes involved in their formation, evolution and migration. The Exoplanetary 8 Science group at the University of New South Wales is utilising the new CYCLOPS2 fibre feed in conjunction with the UCLES spectrograph at the Anglo-Australian Telescope to carry out high precision Doppler spectroscopy of candidate transit planet systems. In addition, our team is carrying out measurements of the Rossiter-McLaughlin (RM) effect in transiting exoplanets. The RM anomaly for transiting planets allows the measurement of the alignment between a planet's orbital plane and its host star's spin axis, known as spin-orbit alignment. This measurement is a crucial component for studying the processes involved in planetary formation and migration. We have carried out measurements of this anomaly for a recently discovered exoplanetary system. Preliminary results indicate that this system is significantly in spin-orbit misalignment by about -90 degrees. I will discuss this exciting result and its potential implications for other planetary systems.!

108 Session 8: Evolution of Planetary Systems!

8.07!Poster ! ✩✩✩✩✩Student Emeline Bolmont Laboratoire d'Astrophysique de Bordeaux, France Franck Selsis, Sean N. Raymond, Jeremy Leconte, Franck Hersant, Anne-Sophie Maurin, & Jessica Pericaud Tidal dissipation and eccentricity pumping: Implications for the depth of the secondary eclipse of 55 Cnc e We use the super Earth 55 Cnc e as a case study to address an observable effect of tidal heating. This transiting short-period planet belongs to a compact multiple system with massive planets. We investigate whether planet- planet interactions can force the eccentricity of this planet to a level affecting the eclipse depth observed with Spitzer. Using the constant time lag tidal model, we first calculate the observed planet flux as a function of albedo and eccentricity, for different tidal dissipation constants and for two extreme cases: a planet with no heat redistribution and a planet with full heat redistribution. We derive the values of albedo and eccentricity that match the observed transit depth. We then perform N-body simulations of the planetary system including tides and General Relativity to follow the evolution of the eccentricity of planet e. We compare the range of eccentricities given by the simulations with the eccentricities required to alter the eclipse depth.Using our nominal value for the dissipation constant and the most recent estimates of the orbital elements and masses of the 55 Cnc planets, we find that the eccentricity of planet e can be large enough to contribute at a measurable level to the thermal emission measured with Spitzer. This affects the constraints on the albedo of the planet, which can be as high as 0.9 (instead of 0.55 when ignoring tidal heating). We also derive a maximum value for the eccentricity of planet e directly from the eclipse depth: e<0.015 assuming Earth's dissipation constant.Transiting exoplanets in multiple planet systems -- like 55 Cancri -- are exceptional targets for testing tidal models because their tidal luminosity may be observable. Future multi-wavelengths observations of eclipse depth and phase curves (for instance with EChO and JWST) should allow us to better resolve the temperature map of these planets and break the degeneracy between albedo and tidal heating that remains for single band observations. In addition, an accurate determination of the eccentricity will make it possible to constrain the dissipation rate of the planet and to probe its internal structure.!

8.08!Poster Boris Gaensicke University of Warwick, UK Jay Farihi, Detlev Koester, & Jonathah Girven The chemistry of exo-planetary material Exo-planet science is rapidly growing from discovery to characterisation. Most of our current knowledge regarding the intrinsic properties of planets comes from transit studies: we now routinely measure the mean densities of planets, and gain insight into the composition of their atmospheres. Yet, it is impossible to determine the bulk elemental composition of extra-solar planets orbiting their host stars. The study of evolved planetary systems around white dwarfs provides an orthogonal approach to this problem. The vast majority of all known planet host stars, including the Sun, will eventually evolve into red giants, devouring close-in planets, and finally end their lives as white dwarfs: extremely dense Earth-sized stellar embers. During their post main sequence evolution stars lose substantial amounts of mass. Consequently, the orbits of their minor and major planets will widen. In the solar system, Mars, the asteroid belt, and all the giant planets will escape vaporation, and the same is true for many of the known exo-planets. It is hence certain that a significant fraction of the known white dwarfs were once host stars 8 to planets, and many of them still have remnants of planetary systems.The detection of metals in the atmospheres of white dwarfs is the unmistakable signpost of such evolved planetary systems. The strong surface gravity of white dwarfs causes metals to sink out of the atmosphere on time-scales much shorter than their cooling ages, leading unavoidably to pristine H/He atmospheres. Therefore any metals detected in the atmosphere of a white dwarf imply recent or ongoing accretion of planetary debris. In fact, planetary debris is also detected as circumstellar dust and gas around a number of white dwarfs. These debris disks are formed from the tidal disruption of asteroids or Kuiper belt-like objects, stirred up by left-over planets, and are subsequently accreted onto the white dwarf, imprinting their abundance pattern into its atmosphere.Determining the photospheric abundances of debris-polluted white dwarfs is

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hence entirely analogue to the use of meteorites, "rocks that fell from the sky", for measuring the abundances of planetary material in the solar system. I will report the results of an unbiased HST/COS ultraviolet spectroscopic survey of 90 young (~100Myr) white dwarfs: (1) nearly 50% of all targets display photospheric Si, indicating recent, or ongoing accretion of planetary debris. This frequency of debris-polluted white dwarfs is about a factor two higher than previously determined by (less sensitive) ground-based surveys.(2) For 22 stars we measure debris abundances for both C and Si. The wide range of C/Si ratios that we detect, ranging from solar to extremely carbon-depleted, is suggestive of a variety of parent bodies that formed over a range of orbital separations of the former host star. Intriguingly, we find the lowest carbon abundances in those white dwarfs accreting at the highest rates, consistent with an origin from large, rocky bodies that formed within the snow line.(3) The potential existence of "carbon planets" has attracted much discussion over the past few years. For 10 stars we measure debris abundances for both O and C, none of them exhibits a C/O ratio larger than solar, ruling that the debris in these systems originates from "carbon" planets.(4) In the four stars with the highest accretion rates, we detect five to eleven elements. In all cases, the C/Si ratio is comparable to that of the Bulk Earth. However, the relative abundances of Mg, Si, and O show a wide range of ratios, similar to the range found in the solar system among different meteorite classes. We detect very strong evidence for differentiated planetary material, in the form of Fe, Cr, and S over-abundances. Finally, Al/Ca is consistent with the ratio observed among solar system bodies. In summary, the growing number of detailed studies of planetary debris around white dwarfs begins to provide statistical insight into the bulk abundances of exo-planetary material, which will constrain and guide models of planet formation.!

8.09!Poster Christiane Helling University of St Andrews, UK Moira Jardine, Declan Diver, Craig Stark, Paul Rimmer, Isabel Rodriguez-Barrera, & Soeren Witte Electrostatic break-down in ultra-cool planetary atmospheres The steady increase of the sample of known extrasolar planets broadens our knowledge and at the same time, challenges our understanding. The evolution of a planet is influenced, amongst other things, by how quickly the planet can cool. This, in turn, depends on how much clouds form. Clouds further determine the composition of the atmospheric gas-phase, and they can change the electric state of the ambient gas from which they form. We have studied the formation of mineral clouds in planetary atmospheres by a kinetic approach modeling seed formation and growth/evaporation under the influence of gravitational settling and element depletion. Our model allows us to predict the size distribution, the material composition of the cloud particles, and the charge carrying surface amongst other dust properties. These results have recently been used to study if mineral clouds can be charged and under which conditions a mineral cloud would experience an electric field breakdown, leading to lightning or other transient luminous events. Our results suggest that turbulent dust-dust collisions are energetic enough to charge the cloud particles alone. We further show that different intra-cloud discharge processes dominate at different heights inside and above clouds, and we estimate the efficiency with which lightning may occur in ultra- cool atmospheres. We are further in the position to assess the potential for lighting and other plasma phenomena 8 across the whole (Teff, log(g),metallicity)-grid of Drift-Phoenix model atmospheres. Drift-Phoenix models combine our kinetic cloud formation model with the Phoenix radiative transfer code, where clouds are an element sink and opacity source. No non-equilibrium charge processes are taken into account by the Drift-Phoenix simulations.The major result of our present research efforts is that thermally non-ionised, ultra-cool planetary atmospheres can be turned into a plasma by various local and global processes and that this may trigger sporadic Xray and/or radio emissions and change the composition of the local atmospheric gas.!

110 Session 8: Evolution of Planetary Systems!

8.10!Poster ! ✩✩✩✩✩Student Jason Hwang Northwestern University, Center for Interdisciplinary Exploration and Research in Astrophysics, USA Jason Steffen, & Frederic Rasio Dynamical Stability and Evolution of the Kepler 'Multi' Systems Kepler Multis are tightly packed planetary systems with 2 or more planets and are often on the verge of instability. Many systems of this type could have become unstable, resulting in planet-planet scattering and frequent physical collisions. Our goal is to study the outcomes of such instabilities, eventually including detailed 3-D hydro calculations of collisions. We begin by investigating Kepler 11, a system with six planets, five of which have orbits within Mercury's orbit. We adopt the parameters reported for Kepler 11 and perturb the masses and/or eccentricities within the nominal error bars. We use Mercury 6.2, an n-body code, to integrate the system for at least ~100 Myr using the general Bulirsch-Stoer integrator with, for now, physical collisions treated in the simple 'sticky-sphere' limit. Next, we generate additional systems by sampling period ratios from the observed distribution for Kepler systems with four or more planets and dynamically integrate each system as described earlier. We are specifically interested in the planet-planet scatterings observed in these simulations and here I present the preliminary results from this ongoing study.!

8.11! Poster Stuart F. Taylor Participation Worldscope/Global Telescope Science, Hong Kong/USA Planets flowing into and polluting the star We present three pieces of evidence of ongoing infall of giant planets into the star: 1. Increasing [Fe/H] in the star is correlated with increasing eccentricity among planets with periods less than 200 days (Taylor 2012b, Taylor 2013a, Dawson & Murray-Clay 2013), 2. The power index of the occurrence distribution of giant (Jupiter) and medium (Neptune) mass planets at the shortest-periods is close to the value of 13/3 expected (Taylor 2012a), and 3. There is a larger infall rate for giant than for medium planets that can be explained by an ongoing flow of giant planets supplying the infall rather than trying to explain the excess of the shortest period planets by saying stars have unexpectedly weak tidal dissipation for planets compared to the tidal dissipation between binary stars.The recent discovery the correlation between increasing [Fe/H] in the star and increasing eccentricity among planets was prompted by the hypothesis that the occurrence distribution evidences a flow of giant planets into the star. We were also motivated by the observation that few hot Jupiter systems have 2nd planets beyond the hot Jupiter, so we were seeking to find evidence if the missing planets may have gone into the star. When we restricted our search to planets with periods less than 200 days, motivated by how scattering from further out may not only have been less likely to scatter other planets into the star, and also that at longer periods high eccentricity migration would be much slower. We found that for planets with eccentricities greater than 0.35 in this period range, [Fe/H] clearly increases with eccentricity. We find a weaker correlation for planets with longer periods. This increase led us to consider that the pollution signal may get washed out of the surface layer of the star during the time it takes for migration to less eccentric orbits.The recent finding that the short-period pileup of giant planets is a feature of higher metallicity planets has been presented as evidence that the pile up results from giant planet-planet scattering. This scattering occurs mostly in planet systems that are more crowded with giant planets due to higher initial metallicity leading to higher rates of giant planet formation (Dawson and Murray-Clay 2013; hereafter DM13). This could also explain why even for metal-rich planets (DM13) there are fewer planets in the pileup of giant planets in the Kepler field, that the explanation that stars in the above-disk region of the Kepler field are older than stars in the solar neighborhood (Howard et al. 2012) could still be why there is less of a pileup in the Kepler sample. DM13 attribute the [Fe/H] with eccentricity correlation to higher rates of giant planet formation in the presence of higher initial iron content. We 8 believe enhanced formation alone would not explain the decreasing correlation with increasing period, but suggest that this could lead to a higher rate of scattered planets, such that the final iron content could be due to both higher initial iron further increased by pollution.In an effort to differentiate between these hypotheses, we compare the [Fe/ H] of the system HD80606, which hosts an extremely eccentric planet, of 0.43 +/- 0.06 with that of its companion HD80607 of 0.38 +/- 0.06. These values may support the scenario of high initial iron leading to pollution of the star further increasing the planet host's [Fe/H], but given the high uncertainty and the fact that binaries can vary in [Fe/ H], we call for planet searches to target more systems of similarly widely separated stars of close to the same mass. (Unfortunately most planet host companion stars are smaller stars that due to their larger convection zones

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of [Fe/H] are difficult).We present a comparison of the occurrence distributions of giant and medium planets that demonstrates that the excess of the shortest-period giant planets is better explained by an ongoing resupply of giant planets. A higher rate of scattering of giant planets than of medium planets could supply this flow. If there is such a flow, then the excess of the shortest period planets need not be explained by unexpectedly weak tidal dissipation in the star. We show how the occurrence distribution of medium planets indicates only moderately weak tidal dissipation in the star, and how the presence of a flow best solves this discrepancy. We show that the number of planets required could be reasonably supplied by planet scattering. We also show how such a flow of giant planets into the star may be observed by transient events in neighboring galaxies, and by searching for more objects such as the “bloatars” found by Spezzi et al. (2011) whose best explanation is that these objects are stars surrounded by planet material released in Roche lobe overflow.We present plans to further validate this model. We are further comparing the numbers of planets at each stage of inward migration. We are comparing the time scales of migration with the time scales of mixing of pollution. Planet migration has produced some of the biggest surprises from the discoveries of large numbers of planets. Not only does migration shape the distribution of planets, it may affect the stars as well, in ways only now becoming observable. We will address important questions raised by planets falling into stars.!

8.12!Poster Amaury Triaud MIT, USA Distinguishing planet migration processes While it is accepted that hot Jupiters do not form in situ, the manner with which they migrated from beyond the ice line to within a fraction of an AU remains a subject of debate. Disc-driven migration was long thought to be a prevalent mechanism. Observations of a large fraction of the hot Jupiter on inclined orbit, sometime retrograde, with respect to the star has shed doubt and gave credence to dynamical interactions followed by a tidal migration. So close to the star tides dominate and probably change the distribution in orbital periods and spin-orbit angles. We observe an evolving planet population instead of a static distribution. This renders our interpretation of the data hard.I will review published observations, show new results and compare several observables to what one would expect each mechanism to produce. Finally I will indicate which additional observations, for example using GAIA, or directly imaged systems, are likely to help us distinguish between the processes of migration and learn about them.!

8.13!Poster Andreas Quirrenbach Landessternwarte Heidelberg, Germany & CARMENES Consortium CARMENES: Blue Planets Orbiting Red Dwarfs CARMENES (Calar Alto high-Resolution search for M dwarfs with Exo-earths with Near-infrared and optical Echelle Spectrographs) is a next-generation instrument for the 3.5m telescope at the Calar Alto Observatory, built by a consortium of eleven Spanish and German institutions. The CARMENES instrument consists of two separate 8 echelle spectrographs covering the wavelength range from 0.55 to 1.7 microns at a spectral resolution of R = 82,000, fed by fibers from the Cassegrain focus of the telescope. Both spectrographs are housed in temperature- stabilized vacuum tanks, to enable a long-term 1m/s radial velocity precision employing a simultaneous calibration with Th-Ne and U-Ne emission line lamps.CARMENES has been optimized for a search for terrestrial planets in the habitable zones (HZs) of low-mass stars, which may well provide our first chance to study environments capable of supporting the development of life outside the Solar System. With its unique combination of optical and near- infrared echelle spectrographs, CARMENES will provide better sensitivity for the detection of low-mass planets than any comparable instrument, and a powerful tool for discriminating between genuine planet detections and false positives caused by stellar activity. The CARMENES survey will target 300 M dwarfs in the 2014 to 2018 time frame.!

112 List of Participants

Participant! Country! Email! Presentation Brett Addison! Australia! [email protected]! 8.06 Yukako Aimi! Japan! [email protected] ! 3.07 Richard Alexander! United Kingdom! [email protected]! 4.01 France Allard! France! [email protected]! 5.11 David Anderson! United Kingdom! [email protected]! Sean Andrews! USA! [email protected]! 2.01 Fabien Anthonioz! France! [email protected]! 2.03 David Armstrong! United Kingdom! [email protected]! 5.12 Jean-Charles Augereau! France! [email protected]! 6.04 Vanessa Bailey ! USA! [email protected]! 1.07 Kévin Baillie! France! [email protected]! 7.08 Gaspar Bakos! USA! [email protected]! 5.13 Nick Ballering! USA! [email protected]! 6.07 Michele Bannister! Canada! [email protected]! Sara Barber! USA! [email protected]! 6.08 Jason W. Barnes! USA! [email protected]! 5.14 Mary Barsony ! USA! [email protected]! 3.08 Jean-Loup Baudino! France! [email protected]! 5.16 Daniel Bayliss! Australia! [email protected]! 5.17 Thomas Beatty ! USA! [email protected]! 5.18 Will Best! USA! [email protected]! 3.09 Beth Biller! Germany! [email protected]! 1.01 Anthony Boccaletti! France! [email protected]! 4.08 David Bohlender! Canada! [email protected]! Emeline Bolmont! France! [email protected]! 8.07 Mariangela Bonavita! Italy! [email protected]! 1.08 Mickaël Bonnefoy! Germany! [email protected]! 5.05 Amy Bonsor! France! [email protected]! 6.09 Mark Booth! Canada! [email protected]! 6.10 Kim Bott! Australia! [email protected]! 5.19 Brendan Bowler! USA! [email protected]! 1.05 Tim Brandt! USA! [email protected]! 1.09 Hannah Broekhoven-Fiene! Canada! [email protected]! 3.10 Joanna Brown! USA! [email protected]! 2.08 Ludmila Carone! Belgium! [email protected]! 7.09 John Carpenter! USA! [email protected]! 4.02 Sebastien Charnoz! France! [email protected]! 7.10 Eugene Chiang! USA! [email protected]! 3.03 Elodie Choquet! USA! [email protected]! 1.10 Duncan Christie! USA! [email protected]! 5.20 Christian Clanton! USA! [email protected]! 3.11 Laird Close! USA! [email protected]! 1.11 Christophe Cossou! France! [email protected]! 7.06 Nicolas Cuello! France! [email protected]! Thayne Currie! Canada! [email protected]! 1.12 Claire Davies! United Kingdom! [email protected]! 4.09 Bekki Dawson! USA! [email protected]! 8.02 Maria de Juan Ovelar! Netherlands! [email protected]! 3.12 Ramiro de la Reza! Brazil! [email protected]! 6.11 Robert De Rosa! USA! [email protected]! 6.12 Denis Defrère! U.S! [email protected]! 6.13 James Di Francesco! Canada! [email protected]! 2.09

113 List of Participants

Participant! Country! Email! Presentation Jack Dobinson! United Kingdom! [email protected]! 6.14 Sally Dodson-Robinson! USA! [email protected]! 2.10 Ruobing Dong! USA! [email protected]! 4.10 René Doyon! Canada! [email protected]! 5.21 Zachary H Draper! Canada! [email protected]! Gaspard Duchene! USA! [email protected]! 2.11 Rudolf Dvorak! Austria! [email protected]! 7.07 Jo Barstow! United Kingdom! [email protected]! 5.15 Keigo Enya! Japan! [email protected]! 5.22 Steve Ertel! France! [email protected]! 6.15 Catherine Espaillat! USA! [email protected]! 3.04 Neal Evans! USA! [email protected]! 3.05 Francesca Faedi! United Kingdom! [email protected]! 5.23 Jackie Faherty ! Chile! [email protected]! 1.13 Virginie Faramaz! France! [email protected]! 4.11 Jay Farihi! United Kingdom! [email protected]! 8.05 Julien Faure! France! [email protected]! 3.13 Stephen Fendyke! United Kingdom! [email protected]! Debra Fischer! USA! debra.fi[email protected]! Mike Fitzgerald! USA! mpfi[email protected]! Kate Follette! USA! [email protected]! 3.14 Jonathan Fortney! USA! [email protected]! 5.01 Wes Fraser! Canada! [email protected] Jeffrey Fung! Canada! [email protected]! 6.16 Boris Gaensicke! United Kingdom! [email protected]! 8.08 Eric Gaidos! USA! [email protected]! 5.24 Raphael Galicher! France! [email protected]! 1.02 Antonio Garufi! Switzerland! antonio.garufi@phys.ethz.ch! 2.12 Scott Gaudi! USA! [email protected]! 1.14 Yilen Gomez Maqueo Chew! United Kingdom! [email protected]! 5.25 Jean-François Gonzalez! France! [email protected]! 2.13 James Graham! Canada / USA! [email protected]! Phil Gregory! Canada! [email protected]! 5.26 Pin-Gao Gu! Taiwan! [email protected]! 4.12 Janis Hagelberg! Switzerland! [email protected]! 1.15 Antonio Hales! Chile! [email protected]! 3.15 Stephan Hartmann! Germany! [email protected]! 6.17 Paul M. Harvey ! USA! [email protected]! Yasuhiro Hasegawa! Taiwan! [email protected]! 4.04 Korey Haynes! USA! korey.n.haynes@nasa.gov! 5.10 Raphaëlle Haywood! United Kingdom! [email protected]! 5.04 Leslie Hebb! USA! [email protected]! 5.27 Christiane Helling! United Kingdom! [email protected]! 8.09 Sasha Hinkley! USA! [email protected]! 1.16 Tobias C. Hinse ! South Korea! [email protected]! 5.28 John Hodgson II! USA! [email protected]! 5.29 Wayne Holland! United Kingdom! [email protected]! 6.18 Derek Homeier! France! [email protected]! 5.30 Jonti Horner! Australia! [email protected]! 5.31 Xu (Chelsea) Huang! USA! [email protected]! 5.32 Elsa Huby ! France! [email protected]! 1.17 Meredith Hughes! USA! [email protected]! 6.19

114 List of Participants

Participant! Country! Email! Presentation Jason Hwang! USA! [email protected]! 8.10 Mike Ireland! Australia! [email protected]! 4.06 Alan Jackson! United Kingdom! [email protected]! 6.20 Marshall Johnson! USA! [email protected]! 5.33 Daniel Jontof-Hutter! USA! [email protected]! 5.34 Marc Joos! France! [email protected]! 3.16 Andres Jordan! Chile! [email protected]! 6.21 Paul Kalas! USA! [email protected]! 4.07 JJ Kavelaars! Canada! [email protected] Grant Kennedy ! United Kingdom! [email protected]! 4.05 Matthew Kenworthy ! Netherlands! [email protected]! 1.18 Jacques Kluska! France! [email protected]! 2.14 Mihoko Konishi! Japan! [email protected]! 1.19 Quinn Konopacky ! Canada! [email protected]! 5.35 Taisiya Kopytova! Germany! [email protected]! 4.13 Quentin Kral ! France! [email protected]! 6.22 Adam L. Kraus! USA! [email protected]! 8.03 Alexander Krivov! Germany! [email protected] Sylvestre Lacour! France! [email protected]! 2.15 Anne-Marie Lagrange! France! [email protected]! 5.36 Michiel Lambrechts! Sweden! [email protected]! 7.02 Samantha Lawler! Canada! [email protected]! 5.03 Zoë Leinhardt! United Kingdom! [email protected]! 3.01 Jean-Francois Lestrade! France! [email protected]! 6.23 Min-Kai Lin! Canada! [email protected]! 4.14 Douglas Lin! USA! [email protected]! Yoram Lithwick! USA! [email protected]! 5.37 Michael Liu! USA! [email protected]! 1.20 Joe Llama! United Kingdom! [email protected]! 5.09 Torsten Löhne! Germany! [email protected]! 6.24 Meredith MacGregor! USA! [email protected]! 6.02 Bruce Macintosh! USA! [email protected]! 1.21 Sarah Maddison! Australia! [email protected]! 6.25 Thomas I. Maindl! Austria! [email protected]! Anne-Lise Maire! France! [email protected]! 1.06 Jerome Maire! Canada! [email protected]! 1.22 Jared Males ! USA! [email protected]! 1.23 Carlo Felice Manara! Germany! [email protected]! 4.15 Rosemary Mardling! Australia! [email protected]! 8.01 Naibi Mariñas! USA! [email protected]fl.edu! 3.17 Christian Marois! Canada! [email protected]! 1.24 Jonathan P. Marshall! Spain! [email protected]! 6.05 David Martin! Switzerland! [email protected]! 3.18 Rebecca Martin! USA! [email protected]! 3.18 Brenda Matthews! Canada! [email protected]! 6.26 Dimitri P. Mawet! Chile! [email protected]! 1.25 Kyle Mede! Japan! [email protected]! 1.26 Heloise Meheut! France! [email protected]! 3.19 Jonathan Menu! Belgium! [email protected]! 2.06 Farzana Meru! Switzerland! [email protected]! 3.20 Dino Mesa ! Italy! [email protected]! 1.27 Tiffany Meshkat! Netherlands! [email protected]! 1.28

115 List of Participants

Participant! Country! Email! Presentation Stanimir Metchev! USA! [email protected]! 1.29 Brian Metzger! USA! [email protected]! 6.27 Cezary Migaszewski! Poland! [email protected]! 5.38 Max Millar-Blanchaer! Canada! [email protected]! 1.30 Julien Milli! France! [email protected]! 6.28 Caroline Morley! USA! [email protected]! 1.31 Katie Morzinski! USA! [email protected]! 5.07 Fatemeh Motalebi! Switzerland! [email protected]! Matthias Müller! Germany! [email protected]! 5.39 Ruth Murray-Clay ! USA! [email protected]! 4.03 Erick Nagel! Mexico! [email protected]! 4.16 Valerio Nascimbeni! Italy! [email protected]! 5.08 Henry Ngo! USA! [email protected]! 3.21 Eric Nielsen! USA! [email protected]! 1.32 Åke Nordlund! Denmark! [email protected]! 3.02 Jack O'Malley-James! United Kingdom! [email protected]! 7.11 Chris Ormel! USA! [email protected]! 3.22 Mayra Osorio! Spain! [email protected]! 3.06 Rahul Patel! USA! [email protected]! 6.29 Jenny Patience! USA! [email protected]! 4.17 Matthew Penny! USA! [email protected]! 1.33 Marshall Perrin! USA! [email protected]! 6.30 Cristobal Petrovich! USA! [email protected]! 7.12 Neil Phillips! Chile! [email protected]! 6.06 Rafael Pinotti! Brazil! [email protected]! Giampaolo Piotto! Italy! [email protected] ! Ana-Maria Piso! USA! [email protected]! 7.03 Don Pollacco! United Kingdom! [email protected]! Ralph Pudritz! Canada! [email protected]! 7.04 Chunhua Qi! USA! [email protected]! 2.04 Andreas Quirrenbach! Germany! [email protected]! 8.13 Roman Rafikov! USA! [email protected]! 7.01 Abhi Rajan! USA! [email protected]! 5.40 Julien RAMEAU! France! [email protected]! 1.34 Emily Rauscher! USA! [email protected]! 7.13 Francoise Remus! France! [email protected]! 7.14 Elisabetta Rigliaco! USA! [email protected]! 4.18 Paul B Rimmer! United Kingdom! [email protected]! 5.41 Adam Ritchey ! USA! [email protected]! 6.31 Timothy J. Rodigas! USA! [email protected]! 2.07 Leslie Rogers! USA! [email protected]! 5.06 Katrin Ros! Sweden! [email protected]! 7.15 Katherine Rosenfeld! USA! [email protected]! 2.16 John Rostron! United Kingdom! [email protected]! 5.42 Raquel Salmeron! Austalia! [email protected]! 4.19 Graeme Salter! Australia! [email protected]! 1.35 Dmitry Savransky ! USA! [email protected]! 1.36 Gerald H. M. Schieven! Canada! [email protected]! Hilke Schlichting! USA! [email protected]! 7.05 Cory Shankman! Canada! [email protected]! Andrew Shannon! United Kingdom! [email protected]! 7.16 Evgenya Shkolnik ! USA! [email protected]! 5.43

116 List of Participants

Participant! Country! Email! Presentation Mar Sierra! Spain! [email protected]! 3.23 Jacob Simon! USA! [email protected]! 3.24 Niki Sipos! Switzerland! [email protected]! 2.17 Andy Skemer! USA! [email protected]! 1.37 Ian Skillen! Spain! [email protected]! Alexis Smith! Poland! [email protected]! 5.44 Karl Stapelfeldt! USA! [email protected]! 2.05 Craig Stark! United Kingdom! [email protected]! 6.32 Christopher Stark! USA! [email protected]! 7.17 Elad Steinberg! Israel! [email protected]! Kate Su! USA! [email protected]! 6.03 Motohide Tamura! Japan! [email protected] ! 1.03 Stuart F. Taylor! Hong Kong! [email protected]! 8.11 Susan Terebey ! USA! [email protected]! 3.25 Johanna Teske! USA! [email protected]! 5.45 Philippe Thebault! France! [email protected]! 6.33 Feng Tian! China! [email protected]! 5.46 Chris Tinney ! Australia! [email protected]! 5.02 Amaury Triaud! Switzerland! [email protected]! 8.12 Trifon Trifonov! Germany! [email protected]! 5.47 Anjali Tripathi! USA! [email protected]! 7.18 Stephane Udry ! Switzerland! [email protected]! Ana Uribe! USA! [email protected]! 4.20 Nienke van der Marel! Netherlands! [email protected]! 2.02 Matthijs van der Wiel! Canada! [email protected]! 3.26 Arthur Vigan! France! [email protected]! 1.04 Simon Walker! United Kingdom! [email protected]! 5.48 Kimberly Ward-Duong! USA! [email protected]! 1.38 Alycia Weinberger! USA! [email protected]! 4.21 Peter Wheatley ! United Kingdom! [email protected]! 5.49 Sloane Wiktorowicz! USA! [email protected]! 5.50 David Wilner! USA! [email protected]! Rob Wittenmyer! Australia! [email protected]! 5.51 Schuyler Wolff! USA! [email protected]! 1.39 Yanqin Wu! Canada! [email protected]! 8.04 Mark Wyatt! United Kingdom! [email protected]! Ji-Wei Xie! Canada! [email protected]! 5.52 Chao-Chin Yang! Sweden! [email protected]! 3.27 Xiaojia Zhang! China! [email protected]! 7.19 Xiaochen Zheng! China! [email protected]! Alice Zurlo! France! [email protected]! 1.40

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