Curriculum Vitae - 24 March 2020
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Lurking in the Shadows: Wide-Separation Gas Giants As Tracers of Planet Formation
Lurking in the Shadows: Wide-Separation Gas Giants as Tracers of Planet Formation Thesis by Marta Levesque Bryan In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy CALIFORNIA INSTITUTE OF TECHNOLOGY Pasadena, California 2018 Defended May 1, 2018 ii © 2018 Marta Levesque Bryan ORCID: [0000-0002-6076-5967] All rights reserved iii ACKNOWLEDGEMENTS First and foremost I would like to thank Heather Knutson, who I had the great privilege of working with as my thesis advisor. Her encouragement, guidance, and perspective helped me navigate many a challenging problem, and my conversations with her were a consistent source of positivity and learning throughout my time at Caltech. I leave graduate school a better scientist and person for having her as a role model. Heather fostered a wonderfully positive and supportive environment for her students, giving us the space to explore and grow - I could not have asked for a better advisor or research experience. I would also like to thank Konstantin Batygin for enthusiastic and illuminating discussions that always left me more excited to explore the result at hand. Thank you as well to Dimitri Mawet for providing both expertise and contagious optimism for some of my latest direct imaging endeavors. Thank you to the rest of my thesis committee, namely Geoff Blake, Evan Kirby, and Chuck Steidel for their support, helpful conversations, and insightful questions. I am grateful to have had the opportunity to collaborate with Brendan Bowler. His talk at Caltech my second year of graduate school introduced me to an unexpected population of massive wide-separation planetary-mass companions, and lead to a long-running collaboration from which several of my thesis projects were born. -
FY08 Technical Papers by GSMTPO Staff
AURA/NOAO ANNUAL REPORT FY 2008 Submitted to the National Science Foundation July 23, 2008 Revised as Complete and Submitted December 23, 2008 NGC 660, ~13 Mpc from the Earth, is a peculiar, polar ring galaxy that resulted from two galaxies colliding. It consists of a nearly edge-on disk and a strongly warped outer disk. Image Credit: T.A. Rector/University of Alaska, Anchorage NATIONAL OPTICAL ASTRONOMY OBSERVATORY NOAO ANNUAL REPORT FY 2008 Submitted to the National Science Foundation December 23, 2008 TABLE OF CONTENTS EXECUTIVE SUMMARY ............................................................................................................................. 1 1 SCIENTIFIC ACTIVITIES AND FINDINGS ..................................................................................... 2 1.1 Cerro Tololo Inter-American Observatory...................................................................................... 2 The Once and Future Supernova η Carinae...................................................................................................... 2 A Stellar Merger and a Missing White Dwarf.................................................................................................. 3 Imaging the COSMOS...................................................................................................................................... 3 The Hubble Constant from a Gravitational Lens.............................................................................................. 4 A New Dwarf Nova in the Period Gap............................................................................................................ -
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Arxiv:2012.09981V1 [Astro-Ph.SR] 17 Dec 2020 2 O
Contrib. Astron. Obs. Skalnat´ePleso XX, 1 { 20, (2020) DOI: to be assigned later Flare stars in nearby Galactic open clusters based on TESS data Olga Maryeva1;2, Kamil Bicz3, Caiyun Xia4, Martina Baratella5, Patrik Cechvalaˇ 6 and Krisztian Vida7 1 Astronomical Institute of the Czech Academy of Sciences 251 65 Ondˇrejov,The Czech Republic(E-mail: [email protected]) 2 Lomonosov Moscow State University, Sternberg Astronomical Institute, Universitetsky pr. 13, 119234, Moscow, Russia 3 Astronomical Institute, University of Wroc law, Kopernika 11, 51-622 Wroc law, Poland 4 Department of Theoretical Physics and Astrophysics, Faculty of Science, Masaryk University, Kotl´aˇrsk´a2, 611 37 Brno, Czech Republic 5 Dipartimento di Fisica e Astronomia Galileo Galilei, Vicolo Osservatorio 3, 35122, Padova, Italy, (E-mail: [email protected]) 6 Department of Astronomy, Physics of the Earth and Meteorology, Faculty of Mathematics, Physics and Informatics, Comenius University in Bratislava, Mlynsk´adolina F-2, 842 48 Bratislava, Slovakia 7 Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, H-1121 Budapest, Konkoly Thege Mikl´os´ut15-17, Hungary Received: September ??, 2020; Accepted: ????????? ??, 2020 Abstract. The study is devoted to search for flare stars among confirmed members of Galactic open clusters using high-cadence photometry from TESS mission. We analyzed 957 high-cadence light curves of members from 136 open clusters. As a result, 56 flare stars were found, among them 8 hot B-A type ob- jects. Of all flares, 63 % were detected in sample of cool stars (Teff < 5000 K), and 29 % { in stars of spectral type G, while 23 % in K-type stars and ap- proximately 34% of all detected flares are in M-type stars. -
XIII Publications, Presentations
XIII Publications, Presentations 1. Refereed Publications E., Kawamura, A., Nguyen Luong, Q., Sanhueza, P., Kurono, Y.: 2015, The 2014 ALMA Long Baseline Campaign: First Results from Aasi, J., et al. including Fujimoto, M.-K., Hayama, K., Kawamura, High Angular Resolution Observations toward the HL Tau Region, S., Mori, T., Nishida, E., Nishizawa, A.: 2015, Characterization of ApJ, 808, L3. the LIGO detectors during their sixth science run, Classical Quantum ALMA Partnership, et al. including Asaki, Y., Hirota, A., Nakanishi, Gravity, 32, 115012. K., Espada, D., Kameno, S., Sawada, T., Takahashi, S., Ao, Y., Abbott, B. P., et al. including Flaminio, R., LIGO Scientific Hatsukade, B., Matsuda, Y., Iono, D., Kurono, Y.: 2015, The 2014 Collaboration, Virgo Collaboration: 2016, Astrophysical Implications ALMA Long Baseline Campaign: Observations of the Strongly of the Binary Black Hole Merger GW150914, ApJ, 818, L22. Lensed Submillimeter Galaxy HATLAS J090311.6+003906 at z = Abbott, B. P., et al. including Flaminio, R., LIGO Scientific 3.042, ApJ, 808, L4. Collaboration, Virgo Collaboration: 2016, Observation of ALMA Partnership, et al. including Asaki, Y., Hirota, A., Nakanishi, Gravitational Waves from a Binary Black Hole Merger, Phys. Rev. K., Espada, D., Kameno, S., Sawada, T., Takahashi, S., Kurono, Lett., 116, 061102. Y., Tatematsu, K.: 2015, The 2014 ALMA Long Baseline Campaign: Abbott, B. P., et al. including Flaminio, R., LIGO Scientific Observations of Asteroid 3 Juno at 60 Kilometer Resolution, ApJ, Collaboration, Virgo Collaboration: 2016, GW150914: Implications 808, L2. for the Stochastic Gravitational-Wave Background from Binary Black Alonso-Herrero, A., et al. including Imanishi, M.: 2016, A mid-infrared Holes, Phys. -
Submillimeter Emission Associated with Candidate Protoplanets
Draft version June 17, 2019 Typeset using LATEX twocolumn style in AASTeX62 Detection of continuum submillimeter emission associated with candidate protoplanets. Andrea Isella,1 Myriam Benisty,2, 3, 4 Richard Teague,5 Jaehan Bae,6 Miriam Keppler,7 Stefano Facchini,8 and Laura Perez´ 2 1Department of Physics and Astronomy, Rice University, 6100 Main Street, MS-108, Houston, TX 77005, USA 2Departamento de Astronom´ıa,Universidad de Chile, Camino El Observatorio 1515, Las Condes, Santiago, Chile 3Unidad Mixta Internacional Franco-Chilena de Astronom´ıa,CNRS, UMI 3386 4Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France. 5Department of Astronomy, University of Michigan, 311 West Hall, 1085 S. University Avenue, Ann Arbor, MI 48109, USA 6Department of Terrestrial Magnetism, Carnegie Institution for Science, 5241 Broad Branch Road, NW, Washington, DC 20015, USA 7Max Planck Institute for Astronomy, K¨onigstuhl 17, 69117, Heidelberg, Germany 8European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching, Germany (Revised June 17, 2019) Submitted to ApJL, Accepted on June 14, 2019 ABSTRACT We present the discovery of a spatially unresolved source of sub-millimeter continuum emission (λ = 855 µm) associated with a young planet, PDS 70 c, recently detected in Hα emission around the 5 Myr old T Tauri star PDS 70. We interpret the emission as originating from a dusty circumplanetary 3 3 disk with a dust mass between 2×10− M and 4:2×10− M . Assuming a standard gas-to-dust ratio of 100, the ratio between the total mass of⊕ the circumplanetary⊕ disk and the mass of the central planet 4 5 would be between 10− − 10− . -
Brown Dwarf: White Dwarf: Hertzsprung -Russell Diagram (H-R
Types of Stars Spectral Classifications: Based on the luminosity and effective temperature , the stars are categorized depending upon their positions in the HR diagram. Hertzsprung -Russell Diagram (H-R Diagram) : 1. The H-R Diagram is a graphical tool that astronomers use to classify stars according to their luminosity (i.e. brightness), spectral type, color, temperature and evolutionary stage. 2. HR diagram is a plot of luminosity of stars versus its effective temperature. 3. Most of the stars occupy the region in the diagram along the line called the main sequence. During that stage stars are fusing hydrogen in their cores. Various Types of Stars Brown Dwarf: White Dwarf: Brown dwarfs are sub-stellar objects After a star like the sun exhausts its nuclear that are not massive enough to sustain fuel, it loses its outer layer as a "planetary nuclear fusion processes. nebula" and leaves behind the remnant "white Since, comparatively they are very cold dwarf" core. objects, it is difficult to detect them. Stars with initial masses Now there are ongoing efforts to study M < 8Msun will end as white dwarfs. them in infrared wavelengths. A typical white dwarf is about the size of the This picture shows a brown dwarf around Earth. a star HD3651 located 36Ly away in It is very dense and hot. A spoonful of white constellation of Pisces. dwarf material on Earth would weigh as much as First directly detected Brown Dwarf HD 3651B. few tons. Image by: ESO The image is of Helix nebula towards constellation of Aquarius hosts a White Dwarf Helix Nebula 6500Ly away. -
The Formation of Brown Dwarfs 459
Whitworth et al.: The Formation of Brown Dwarfs 459 The Formation of Brown Dwarfs: Theory Anthony Whitworth Cardiff University Matthew R. Bate University of Exeter Åke Nordlund University of Copenhagen Bo Reipurth University of Hawaii Hans Zinnecker Astrophysikalisches Institut, Potsdam We review five mechanisms for forming brown dwarfs: (1) turbulent fragmentation of molec- ular clouds, producing very-low-mass prestellar cores by shock compression; (2) collapse and fragmentation of more massive prestellar cores; (3) disk fragmentation; (4) premature ejection of protostellar embryos from their natal cores; and (5) photoerosion of pre-existing cores over- run by HII regions. These mechanisms are not mutually exclusive. Their relative importance probably depends on environment, and should be judged by their ability to reproduce the brown dwarf IMF, the distribution and kinematics of newly formed brown dwarfs, the binary statis- tics of brown dwarfs, the ability of brown dwarfs to retain disks, and hence their ability to sustain accretion and outflows. This will require more sophisticated numerical modeling than is presently possible, in particular more realistic initial conditions and more realistic treatments of radiation transport, angular momentum transport, and magnetic fields. We discuss the mini- mum mass for brown dwarfs, and how brown dwarfs should be distinguished from planets. 1. INTRODUCTION form a smooth continuum with those of low-mass H-burn- ing stars. Understanding how brown dwarfs form is there- The existence of brown dwarfs was first proposed on the- fore the key to understanding what determines the minimum oretical grounds by Kumar (1963) and Hayashi and Nakano mass for star formation. In section 3 we review the basic (1963). -
Marta L. Bryan
Marta L. Bryan 501 Campbell Hall #3411 Email: [email protected] University of California at Berkeley Homepage: w.astro.berkeley.edu/∼martalbryan Berkeley, CA 94720-3411 Appointments NASA Hubble Fellowship Program Sagan Fellow, UC Berkeley Astronomy Fall 2021 - present Department 51 Pegasi b Postdoctoral Fellow, UC Berkeley Astronomy Department 2018 - Fall 2021 Education PhD in Astrophysics, California Institute of Technology May 2018 Advisor: Prof. Heather Knutson Thesis: Lurking in the Shadows: Wide-Separation Gas Giants as Tracers of Planet Formation MS in Astrophysics, California Institute of Technology June 2014 BA cum laude with High Honors in Astrophysics, Harvard University June 2012 Undergraduate Thesis Advisor: Prof. David Latham Thesis: Characterizing Qatar-2b: A Hot Jupiter Orbiting a K Dwarf Research Interests Exploring the formation, evolution, and architectures of planetary systems Characterizing exoplanet rotation rates and atmospheres using high-resolution spectroscopy High-contrast AO imaging of exoplanets and brown dwarfs Constraining the frequencies of gas giants in systems hosting different populations of terrestrial and ice giant planets Bridging the gap between radial velocity and direct imaging survey sensitivities to planets using radial velocity trends Awards and Honors NASA Hubble Fellowship Program Sagan Fellowship 2021 51 Pegasi b Postdoctoral Fellowship 2018 NASA Hubble Fellowship Program Sagan Fellowship (declined) 2018 David and Barbara Groce Grant to attend the Exoplanets I meeting in Davos 2016 Switzerland, California Institute of Technology AAS 2015 International Travel Grant 2015 National Science Foundation Graduate Research Fellowship Honorable Mention 2014, 2013 Chambliss Astronomy Achievement Student Award Honorable Mention, AAS 2014 Moffet Fellowship, California Institute of Technology 2012-2013 Origins of Life Research Grant, Harvard University 2011-2012 Leo Goldberg Prize for outstanding undergraduate thesis work, Harvard University 2011 U.S. -
Binocular Challenge Here
AHSP Binocular Observing Award Compiled by Phil Harrington www.philharrington.net • To qualify for the BOA pin, you must see 15 of the following 20 binocular targets. Check off each as you spot them. Seen # Object Const. Type* RA Dec Mag Size Nickname 1. M13 Her GC 16 41.7 +36 28 5.9 16' Great Hercules Globular 2. M57 Lyr PN 18 53.6 +33 02 9.7 86"x62" Ring Nebula 3. Collinder 399 Vul AS 19 25.4 +20 11 3.6 60' Coathanger/Brocchi’s Cluster 3.1 4. Albireo Cyg Dbl 19 30.7 +27 57 35” Color Contrasting Double 5.1 5. M27 Vul PN 19 59.6 +22 43 8.1 8’x6’ Dumbbell Nebula 6. NGC 6992 Cyg SNR 20 56.4 +31 43 - 60'x8 Veil Nebula (east) 7. NGC 7000 Cyg BN 20 58.8 +44 20 - 120'x100' North America Nebula 8. M15 Peg GC 21 30.0 +12 10 7.5 12’ Great Pegasus Cluster 9. M39 Cyg OC 21 32.2 +48 26 4.6 32' 10. Barnard 168 Cyg DN 21 53.2 +47 12 - 100'x10' West of Cocoon Nebula 11. IC 5146 Cyg BN/OC 21 53.5 +47 16 - 12'x12' Cocoon Nebula 12. M110 And Gx 00 40.4 +41 41 10 17’x10’ 13. M32 And Gx 00 42.8 +40 52 10 8’x6’ 14. M31 And Gx 00 42.8 +41 16 4.5 178’ Andromeda Galaxy 15. NGC 457 Cas OC 01 19.1 +58 20 6.4 13’ Owl Cluster/ET Cluster 16. -
A Review on Substellar Objects Below the Deuterium Burning Mass Limit: Planets, Brown Dwarfs Or What?
geosciences Review A Review on Substellar Objects below the Deuterium Burning Mass Limit: Planets, Brown Dwarfs or What? José A. Caballero Centro de Astrobiología (CSIC-INTA), ESAC, Camino Bajo del Castillo s/n, E-28692 Villanueva de la Cañada, Madrid, Spain; [email protected] Received: 23 August 2018; Accepted: 10 September 2018; Published: 28 September 2018 Abstract: “Free-floating, non-deuterium-burning, substellar objects” are isolated bodies of a few Jupiter masses found in very young open clusters and associations, nearby young moving groups, and in the immediate vicinity of the Sun. They are neither brown dwarfs nor planets. In this paper, their nomenclature, history of discovery, sites of detection, formation mechanisms, and future directions of research are reviewed. Most free-floating, non-deuterium-burning, substellar objects share the same formation mechanism as low-mass stars and brown dwarfs, but there are still a few caveats, such as the value of the opacity mass limit, the minimum mass at which an isolated body can form via turbulent fragmentation from a cloud. The least massive free-floating substellar objects found to date have masses of about 0.004 Msol, but current and future surveys should aim at breaking this record. For that, we may need LSST, Euclid and WFIRST. Keywords: planetary systems; stars: brown dwarfs; stars: low mass; galaxy: solar neighborhood; galaxy: open clusters and associations 1. Introduction I can’t answer why (I’m not a gangstar) But I can tell you how (I’m not a flam star) We were born upside-down (I’m a star’s star) Born the wrong way ’round (I’m not a white star) I’m a blackstar, I’m not a gangstar I’m a blackstar, I’m a blackstar I’m not a pornstar, I’m not a wandering star I’m a blackstar, I’m a blackstar Blackstar, F (2016), David Bowie The tenth star of George van Biesbroeck’s catalogue of high, common, proper motion companions, vB 10, was from the end of the Second World War to the early 1980s, and had an entry on the least massive star known [1–3]. -
The Twofold Debris Disk Around HD 113766 A⋆
A&A 551, A134 (2013) Astronomy DOI: 10.1051/0004-6361/201220904 & c ESO 2013 Astrophysics The twofold debris disk around HD 113766 A? Warm and cold dust as seen with VLTI/MIDI and Herschel/PACS J. Olofsson1, Th. Henning1, M. Nielbock1, J.-C. Augereau2, A. Juhàsz3, I. Oliveira4, O. Absil5, and A. Tamanai6 1 Max Planck Institut für Astronomie, Königstuhl 17, 69117 Heidelberg, Germany e-mail: [email protected] 2 UJF-Grenoble 1/CNRS-INSU, Institut de Planétologie et d’Astrophysique de Grenoble (IPAG), UMR 5274, Grenoble, France 3 Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, The Netherlands 4 Astronomy Department, University of Texas at Austin, 1 University Station C1400, Austin, TX 78712-0259, USA 5 Département d’Astrophysique, Géophysique et Océanographie, Université de Liège, 17 Allée du Six Août, 4000 Sart Tilman, Belgium 6 University Heidelberg, Kirchhoff-Institut für Physik, 69120 Heidelberg, Germany Received 13 December 2012 / Accepted 22 January 2013 ABSTRACT Context. Warm debris disks are a sub-sample of the large population of debris disks, and display excess emission in the mid-infrared. Around solar-type stars, very few objects (∼2% of all debris disks) show emission features in mid-IR spectroscopic observations that are attributed to small, warm silicate dust grains. The origin of this warm dust could be explained either by a recent catastrophic collision between several bodies or by transport from an outer belt similar to the Kuiper belt in the solar system. Aims. We present and analyze new far-IR Herschel/PACS photometric observations, supplemented by new and archival ground-based data in the mid-IR (VLTI/MIDI and VLT/VISIR), for one of these rare systems: the 10–16 Myr old debris disk around HD 113766 A. -
Spitzer Team Says Debris Disk Could Be Forming Infant Terrestrial Planets 14 December 2005
Spitzer Team Says Debris Disk Could Be Forming Infant Terrestrial Planets 14 December 2005 an asteroid belt, roughly at the distance Jupiter is from our sun." "This object is very unusual in the context of all the others we've looked at," said University of Arizona assistant astronomy Professor Michael R. Meyer, a colleague in the discovery. Meyer directs a Spitzer Legacy project to study solar system formation and evolution in a sample of 328 young sun-like stars in the Milky Way. The project turned up the unusual system. "This is the only such debris disk among the 33 sun- like stars we've studied in our project so far, and one of only five such objects known," Meyer said. The star, named HD 12039, is about 30 million years old, or the age of the sun when the terrestrial planets are thought to have been 80 percent complete and the Earth-moon system formed, the Astronomers have found a debris disk around a astronomers said. It is roughly 137 light years sun-like star that may be forming or has formed its away, or the distance light travels in 137 years. terrestrial planets. The disk - a probable analog to our asteroid belt - may have begun a solar-system- HD 12039 is a "G" type star like our sun, a yellow scale demolition derby, where the rocky remains of star with surface temperatures between 5,000 and failed planets collide chaotically. 7,000 degrees Fahrenheit. It hasn't yet settled into the "main sequence," or mature nuclear-burning Image: Scientists can characterize a disk by phase as our sun has.