Towards a Dynamics-Based Estimate of the Extent of HR 8799'S
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Young Nearby Stars by Adam Conrad Schneider (Under The
Young Nearby Stars by Adam Conrad Schneider (Under the Direction of Professor Inseok Song) Abstract Nearby young stars are without equal as stellar and planetary evolution laboratories. The aim of this work is to use age diagnostic considerations to execute a complete survey for new nearby young stars and to efficiently reevaluate and constrain their ages. Because of their proximity and age, young, nearby stars are the most desired targets for any astrophysical study focusing on the early stages of star and planet formation. Identifying nearby, young, low-mass stars is challenging because of their inherent faint- ness and age diagnostic degeneracies. A new method for identifying these objects has been developed, and a pilot study of its effectiveness is demonstrated by the identification of two definite new members of the TW Hydrae Association. Nearby, young, solar-type stars are initially identified in this work by their fractional X-ray luminosity. The results of a large-scale search for nearby, young, solar-type stars is presented. Follow-up spectroscopic observations are taken in order to measure various age diagnostics in order to accurately assess stellar ages. Age, one of the most fundamental properties of a star, is also one of the most difficult to determine. While a variety of proce- dures have been developed and utilized to approximate ages for solar-type stars, with varying degrees of success, a comprehensive age-dating technique has yet to be constructed. Often- times, different methods exhibit contradictory or conflicting findings. Such inconsistencies demonstrate the value of a uniform method of determining stellar ages. -
The Chara Array Angular Diameter of Hr 8799 Favors Planetary Masses for Its Imaged Companions
The Astrophysical Journal, 761:57 (15pp), 2012 December 10 doi:10.1088/0004-637X/761/1/57 C 2012. The American Astronomical Society. All rights reserved. Printed in the U.S.A. THE CHARA ARRAY ANGULAR DIAMETER OF HR 8799 FAVORS PLANETARY MASSES FOR ITS IMAGED COMPANIONS Ellyn K. Baines1, Russel J. White2, Daniel Huber3, Jeremy Jones2, Tabetha Boyajian2, Harold A. McAlister2, Theo A. ten Brummelaar2, Nils H. Turner2, Judit Sturmann2, Laszlo Sturmann2, P. J. Goldfinger2, Christopher D. Farrington2, Adric R. Riedel2, Michael Ireland4, Kaspar von Braun5, and Stephen T. Ridgway6 1 Remote Sensing Division, Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, DC 20375, USA; [email protected] 2 Center for High Angular Resolution Astronomy, Georgia State University, P.O. Box 3969, Atlanta, GA 30302-3969, USA 3 NASA Ames Research Center, Moffett Field, CA 94035, USA 4 Department of Physics & Astronomy, Macquarie University, New South Wales, NSW 2109, Australia 5 NASA Exoplanet Science Institute, California Institute of Technology, 770 S. Wilson Ave., MS 100-22, Pasadena, CA 91125-2200, USA 6 Kitt Peak National Observatory, National Optical Astronomy Observatory, P.O. Box 26732, Tucson, AZ 85726-6732, USA Received 2012 July 3; accepted 2012 September 29; published 2012 November 21 ABSTRACT HR 8799 is an hF0 mA5 γ Doradus-, λ Bootis-, Vega-type star best known for hosting four directly imaged candidate planetary companions. Using the CHARA Array interferometer, we measure HR 8799’s limb-darkened angular diameter to be 0.342 ± 0.008 mas (an error of only 2%). By combining our measurement with the star’s parallax and photometry from the literature, we greatly improve upon previous estimates of its fundamental parameters, including stellar radius (1.44 ± 0.06 R), effective temperature (7193 ± 87 K, consistent with F0), luminosity (5.05 ± 0.29 L), and the extent of the habitable zone (HZ; 1.62–3.32 AU). -
Naming the Extrasolar Planets
Naming the extrasolar planets W. Lyra Max Planck Institute for Astronomy, K¨onigstuhl 17, 69177, Heidelberg, Germany [email protected] Abstract and OGLE-TR-182 b, which does not help educators convey the message that these planets are quite similar to Jupiter. Extrasolar planets are not named and are referred to only In stark contrast, the sentence“planet Apollo is a gas giant by their assigned scientific designation. The reason given like Jupiter” is heavily - yet invisibly - coated with Coper- by the IAU to not name the planets is that it is consid- nicanism. ered impractical as planets are expected to be common. I One reason given by the IAU for not considering naming advance some reasons as to why this logic is flawed, and sug- the extrasolar planets is that it is a task deemed impractical. gest names for the 403 extrasolar planet candidates known One source is quoted as having said “if planets are found to as of Oct 2009. The names follow a scheme of association occur very frequently in the Universe, a system of individual with the constellation that the host star pertains to, and names for planets might well rapidly be found equally im- therefore are mostly drawn from Roman-Greek mythology. practicable as it is for stars, as planet discoveries progress.” Other mythologies may also be used given that a suitable 1. This leads to a second argument. It is indeed impractical association is established. to name all stars. But some stars are named nonetheless. In fact, all other classes of astronomical bodies are named. -
Arxiv:2105.12820V1 [Astro-Ph.EP] 26 May 2021 Known with Exquisite Precision
Draft version May 28, 2021 Typeset using LATEX twocolumn style in AASTeX63 The First Dynamical Mass Measurement in the HR 8799 System 1, 1 2 3 G. Mirek Brandt , ∗ Timothy D. Brandt , Trent J. Dupuy , Daniel Michalik , and Gabriel-Dominique Marleau 4, 5, 6 1Department of Physics, University of California, Santa Barbara, Santa Barbara, CA 93106, USA 2Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh, EH9 3HJ, UK 3European Space Agency (ESA), European Space Research and Technology Centre (ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands 4Institut f¨urAstronomie und Astrophysik, Universit¨atT¨ubingen,Auf der Morgenstelle 10, 72076 T¨ubingen,Germany 5Physikalisches Institut, Universit¨atBern, Gesellschaftsstr. 6, 3012 Bern, Switzerland 6Max-Planck-Institut f¨urAstronomie, K¨onigstuhl17, 69117 Heidelberg, Germany (Received April 7, 2021; Revised May 14, 2021; Accepted May 26, 2021) Submitted to ApJ Letters ABSTRACT HR 8799 hosts four directly imaged giant planets, but none has a mass measured from first principles. We present the first dynamical mass measurement in this planetary system, finding that the innermost +1:9 planet HR 8799 e has a mass of 9:6−1:8 MJup. This mass results from combining the well-characterized orbits of all four planets with a new astrometric acceleration detection (5σ) from the Gaia EDR3 version of the Hipparcos-Gaia Catalog of Accelerations. We find with 95% confidence that HR 8799 e +24 is below 13 MJup, the deuterium-fusing mass limit. We derive a hot-start cooling age of 42−16 Myr for HR 8799 e that agrees well with its hypothesized membership in the Columba association but is also consistent with an alternative suggested membership in the β Pictoris moving group. -
Structure and Evolution of Debris Disks Around F-Type Stars
The Astrophysical Journal Supplement Series,193:4(25pp),2011March doi:10.1088/0067-0049/193/1/4 C 2011. The American Astronomical Society. All rights reserved. Printed in the U.S.A. ! STRUCTURE AND EVOLUTION OF DEBRIS DISKS AROUND F-TYPE STARS. I. OBSERVATIONS, DATABASE, AND BASIC EVOLUTIONARY ASPECTS A. Moor´ 1,I.Pascucci2, A.´ Kosp´ al´ 3,P.Abrah´ am´ 1,T.Csengeri4,L.L.Kiss1,5,D.Apai2,C.Grady6,7,Th.Henning8, Cs. Kiss1, D. Bayliss9,A.Juhasz´ 8,J.Kovacs´ 10,andT.Szalai11 1 Konkoly Observatory of the Hungarian Academy of Sciences, P.O. Box 67, H-1525 Budapest, Hungary; [email protected] 2 Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA 3 Leiden Observatory, Leiden University, Niels Bohrweg 2, NL-2333 CA Leiden, The Netherlands 4 Laboratoire AIM, CEA/DSM, IRFU/Service d’Astrophysique, 91191 Gif-sur-Yvette Cedex, France 5 Sydney Institute for Astronomy, School of Physics A28, University of Sydney, NSW 2006, Australia 6 NASA Goddard Space Flight Center, Code 667, Greenbelt, MD 20771, USA 7 Eureka Scientific, 2452 Delmer Street, Suite 100, Oakland, CA 94602, USA 8 Max-Planck-Institut fur¨ Astronomie, Konigstuhl¨ 17, 69117 Heidelberg, Germany 9 Research School of Astronomy and Astrophysics, The Australian National University, Mount Stromlo Observatory, Cotter Road, Weston Creek, ACT 2611, Australia 10 Gothard Astrophysical Observatory, ELTE University, 9707 Szombathely, Hungary 11 Department of Optics and Quantum Electronics, University of Szeged, 6720 Szeged, Dom´ ter´ 9, Hungary Received 2010 May 30; accepted 2010 December 10; published 2011 January 20 ABSTRACT Although photometric and spectroscopic surveys with the Spitzer Space Telescope remarkably increased the number of well-studied debris disks around A-type and Sun-like stars, detailed analyses of debris disks around F-type stars remained less frequent. -
GEMINI PLANET IMAGER SPECTROSCOPY of the HR 8799 PLANETS C and D
The Astrophysical Journal Letters, 794:L15 (5pp), 2014 October 10 doi:10.1088/2041-8205/794/1/L15 C 2014. The American Astronomical Society. All rights reserved. Printed in the U.S.A. GEMINI PLANET IMAGER SPECTROSCOPY OF THE HR 8799 PLANETS c AND d Patrick Ingraham1, Mark S. Marley2, Didier Saumon3, Christian Marois4, Bruce Macintosh1, Travis Barman5, Brian Bauman6, Adam Burrows7, Jeffrey K. Chilcote8, Robert J. De Rosa9,10, Daren Dillon11,Rene´ Doyon12, Jennifer Dunn4, Darren Erikson4, Michael P. Fitzgerald8, Donald Gavel11, Stephen J. Goodsell13, James R. Graham14, Markus Hartung13, Pascale Hibon13, Paul G. Kalas14, Quinn Konopacky15, James A. Larkin8, Jer´ omeˆ Maire15, Franck Marchis16, James McBride14, Max Millar-Blanchaer15, Katie M. Morzinski17,24, Andrew Norton11, Rebecca Oppenheimer18, Dave W. Palmer6, Jenny Patience9, Marshall D. Perrin19, Lisa A. Poyneer6, Laurent Pueyo19, Fredrik Rantakyro¨ 13, Naru Sadakuni13, Leslie Saddlemyer4, Dmitry Savransky20,Remi´ Soummer19, Anand Sivaramakrishnan19, Inseok Song21, Sandrine Thomas2,22, J. Kent Wallace23, Sloane J. Wiktorowicz11, and Schuyler G. Wolff19 1 Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, CA 94305, USA 2 NASA Ames Research Center, Moffett Field, CA 94035, USA 3 Los Alamos National Laboratory, Los Alamos, NM 87545, USA 4 NRC Herzberg Astronomy and Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7, Canada 5 Lunar and Planetary Laboratory, University of Arizona, Tucson, Arizona 85721-0092, USA 6 Lawrence Livermore National Lab, -
Planet Searching from Ground and Space
Planet Searching from Ground and Space Olivier Guyon Japanese Astrobiology Center, National Institutes for Natural Sciences (NINS) Subaru Telescope, National Astronomical Observatory of Japan (NINS) University of Arizona Breakthrough Watch committee chair June 8, 2017 Perspectives on O/IR Astronomy in the Mid-2020s Outline 1. Current status of exoplanet research 2. Finding the nearest habitable planets 3. Characterizing exoplanets 4. Breakthrough Watch and Starshot initiatives 5. Subaru Telescope instrumentation, Japan/US collaboration toward TMT 6. Recommendations 1. Current Status of Exoplanet Research 1. Current Status of Exoplanet Research 3,500 confirmed planets (as of June 2017) Most identified by Jupiter two techniques: Radial Velocity with Earth ground-based telescopes Transit (most with NASA Kepler mission) Strong observational bias towards short period and high mass (lower right corner) 1. Current Status of Exoplanet Research Key statistical findings Hot Jupiters, P < 10 day, M > 0.1 Jupiter Planetary systems are common occurrence rate ~1% 23 systems with > 5 planets Most frequent around F, G stars (no analog in our solar system) credits: NASA/CXC/M. Weiss 7-planet Trappist-1 system, credit: NASA-JPL Earth-size rocky planets are ~10% of Sun-like stars and ~50% abundant of M-type stars have potentially habitable planets credits: NASA Ames/SETI Institute/JPL-Caltech Dressing & Charbonneau 2013 1. Current Status of Exoplanet Research Spectacular discoveries around M stars Trappist-1 system 7 planets ~3 in hab zone likely rocky 40 ly away Proxima Cen b planet Possibly habitable Closest star to our solar system Faint red M-type star 1. Current Status of Exoplanet Research Spectroscopic characterization limited to Giant young planets or close-in planets For most planets, only Mass, radius and orbit are constrained HR 8799 d planet (direct imaging) Currie, Burrows et al. -
Birth Sites of Young Stellar Associations and Recent Star Formation in a Flocculent Corrugated Disk
MNRAS 000, 000{000 (0000) Preprint 5 August 2020 Compiled using MNRAS LATEX style file v3.0 Birth Sites of Young Stellar Associations and Recent Star Formation in a Flocculent Corrugated Disk Alice C. Quillen1?, Alex R. Pettitt2, Sukanya Chakrabarti3, Yifan Zhang1, Jonathan Gagn´e4;5, and Ivan Minchev6 1Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627, USA 2Department of Physics, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan 3School of Physics and Astronomy, Rochester Institute of Technology, 84 Lomb Memorial Drive, Rochester, NY 14623, USA 4Institut de Recherche sur les Exoplan`etes, Universit´ede Montr´eal, Pavillon Roger-Gaudry, PO Box 6128 Centre-Ville STN, Montr´eal QC H3C 3J7, Canada 5Plan´etarium Rio Tinto Alcan, Espace pour la Vie, 4801 av. Pierre-de Coubertin, Montr´eal, Qu´ebec, Canada 6Leibniz Institut fur¨ Astrophysik Potsdam (AIP), An der Sternwarte 16, D-14482, Potsdam, Germany 5 August 2020 ABSTRACT With backwards orbit integration we estimate birth locations of young stellar associ- ations and moving groups identified in the solar neighborhood that are younger than 70 Myr. The birth locations of most of these stellar associations are at smaller galac- tocentric radius than the Sun, implying that their stars moved radially outwards after birth. Exceptions to this rule are the Argus and Octans associations, which formed outside the Sun's galactocentric radius. Variations in birth heights of the stellar asso- ciations suggest that they were born in a corrugated disk of molecular clouds, similar to that inferred from the current filamentary molecular cloud distribution and dust extinction maps. -
The Formation Mechanism of Gas Giants on Wide Orbits
The Astrophysical Journal, 707:79–88, 2009 December 10 doi:10.1088/0004-637X/707/1/79 C 2009. The American Astronomical Society. All rights reserved. Printed in the U.S.A. THE FORMATION MECHANISM OF GAS GIANTS ON WIDE ORBITS Sarah E. Dodson-Robinson1,4, Dimitri Veras2, Eric B. Ford2, and C. A. Beichman3 1 Astronomy Department, University of Texas, 1 University Station C1400, Austin, TX 78712, USA; [email protected] 2 Astronomy Department, University of Florida, 211 Bryant Space Sciences Center, Gainesville, FL 32111, USA 3 NASA Exoplanet Science Institute, California Institute of Technology, 770 S. Wilson Ave, Pasadena, CA 91125, USA Received 2009 July 29; accepted 2009 October 19; published 2009 November 18 ABSTRACT The recent discoveries of massive planets on ultra-wide orbits of HR 8799 and Fomalhaut present a new challenge for planet formation theorists. Our goal is to figure out which of three giant planet formation mechanisms— core accretion (with or without migration), scattering from the inner disk, or gravitational instability—could be responsible for Fomalhaut b, HR 8799 b, c and d, and similar planets discovered in the future. This paper presents the results of numerical experiments comparing the long-period planet formation efficiency of each possible mechanism in model A star, G star, and M star disks. First, a simple core accretion simulation shows that planet cores forming beyond 35 AU cannot reach critical mass, even under the most favorable conditions one can construct. Second, a set of N-body simulations demonstrates that planet–planet scattering does not create stable, wide-orbit systems such as HR 8799. -
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A&A 637, A9 (2020) Astronomy https://doi.org/10.1051/0004-6361/201937239 & c O. Flasseur et al. 2020 Astrophysics PACO ASDI: an algorithm for exoplanet detection and characterization in direct imaging with integral field spectrographs Olivier Flasseur1, Loïc Denis1, Éric Thiébaut2, and Maud Langlois2 1 Université de Lyon, UJM-Saint-Etienne, CNRS, Institut d’Optique Graduate School, Laboratoire Hubert Curien UMR 5516, 42023 Saint-Etienne, France e-mail: [email protected] 2 Université de Lyon, Université Lyon1, ENS de Lyon, CNRS, Centre de Recherche Astrophysique de Lyon UMR 5574, 69230 Saint-Genis-Laval, France e-mail: [email protected] Received 3 December 2019 / Accepted 6 March 2020 ABSTRACT Context. Exoplanet detection and characterization by direct imaging both rely on sophisticated instruments (adaptive optics and coro- nagraph) and adequate data processing methods. Angular and spectral differential imaging (ASDI) combines observations at different times and a range of wavelengths in order to separate the residual signal from the host star and the signal of interest corresponding to off-axis sources. Aims. Very high contrast detection is only possible with an accurate modeling of those two components, in particular of the back- ground due to stellar leakages of the host star masked out by the coronagraph. Beyond the detection of point-like sources in the field of view, it is also essential to characterize the detection in terms of statistical significance and astrometry and to estimate the source spectrum. Methods. We extend our recent method PACO, based on local learning of patch covariances, in order to capture the spectral and tem- poral fluctuations of background structures. -
Coronagraphic Imaging of Debris Disks from a High Altitude Balloon Platform
Coronagraphic Imaging of Debris Disks From a High Altitude Balloon Platform Stephen Unwin >", Wesley 'Traub", Geoffrey Bryden", Paul Brugarolasa , Pin Chen", Olivier Guyonb, Lynne Hillenbrandc, John Krist", Bruce ~facintoshd , Dimitri 1Ifawete, Bertrand Mennesson", Dwight Moody", Lewis C. Roberts Jr.", Karl Stapelfeldt!, David Stuchlik9, John 'Traugera , and Gautam Vasisht" "Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 bNational Observatory of Japan, 650 N. A'ohoku Place, Hilo, HI 96720 cCalifornia Institute of Technology, Pasadena, CA 91125 dLawrence Livermore National Laboratory, Livermore, CA 94550 eEuropean Southern Observatory, Alonso de Cordova 3107, Vitacura, Casilla 19001, Santiago de Chile 19, Chile fNASA Goddard Space Flight Center, Greenbelt, MD 20771 9NASA Wallops Flight Facility, Wallops Island, VA 23337 ABSTRACT Debris disks around nearby stars are tracers of the planet formation process, and they are a key element of our understanding of the, formation and evolution of extrasolar planeta.ry systems. With multi-color images of a. significant number of disks, we can probe important questions: ca.'1. we learn about planetary system evolution; whflt materials are the disks made of; and can they reveal the presence of planets? :Most disks are known to exist only through their infrared flux excesses as measured by the Spitzer Space Telescope, and through images mesaured by Herschel. The brightest, most exte::tded disks have been imaged with HST, and a few, such as Fomalhaut, can be observed using ground-based telescopes. But the number of good images is still very small, and there are none of disks with densitips as low as the disk associated with the asteroid belt and Edgeworth Kuiper belt in our own Solar System. -
Radial Velocity of Directly Imaged Planets Jean-Baptiste Ruffio, OSIRIS: Quinn M
Radial Velocity of directly imaged planets Jean-Baptiste Ruffio, OSIRIS: Quinn M. Konopacky, Travis Barman, Bruce Macintosh, Kielan K. Wilcomb, Robert J. De Rosa, Jason J. Wang, Ian Czekala, Christian Marois, KPIC: KPIC collaboration, Jason Wang, Evan Morris, Jacques Delorme, Dimitri Mawet, Andrew Skemer, Travis Barman. [email protected] Planetary radial velocity (RV) is one of the science drivers for high Youtube introduction link resolution spectroscopy of exoplanets. It can be used to better constrain the orbital architecture of stellar systems (e.g. eccentricity or obliquity), which can be related to the formation history of exoplanets. Ultimately, planetary RV will even allow the detection of exo-moons. Such measurements are however challenging due to the overwhelming starlight at the small separations corresponding to directly imaged planets. We present RV measurements of the four large gas giant planets orbiting the star HR 8799 (Fig. 1) using OSIRIS and the new KPIC instruments at Keck. Fig. 1: HR 8799 four-planet system from Marois et al. (2010) [1]. The orbital motion of the planets can be visualized here. Moderate resolution spectroscopy (R≈4,000) with OSIRIS/Keck The OSIRIS instrument at Keck has been used to detect molecules (CO and H2O) and characterize the atmosphere of HR 8799 b and c for more than a decade [2,3]. Despite the moderate resolution of the instrument (R≈4,000, K band), we showed that we could measure the RV of HR 8799 b and c with a combined precision of 0.5 km/s using a forward modeling approach. These measurements resolve the degeneracy in the 3D orientation of the system [4].