Multidata Inverse Problems and Bayesian Solution Methods in Astronomy
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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. -
Ghost Imaging of Space Objects
Ghost Imaging of Space Objects Dmitry V. Strekalov, Baris I. Erkmen, Igor Kulikov, and Nan Yu Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109-8099 USA NIAC Final Report September 2014 Contents I. The proposed research 1 A. Origins and motivation of this research 1 B. Proposed approach in a nutshell 3 C. Proposed approach in the context of modern astronomy 7 D. Perceived benefits and perspectives 12 II. Phase I goals and accomplishments 18 A. Introducing the theoretical model 19 B. A Gaussian absorber 28 C. Unbalanced arms configuration 32 D. Phase I summary 34 III. Phase II goals and accomplishments 37 A. Advanced theoretical analysis 38 B. On observability of a shadow gradient 47 C. Signal-to-noise ratio 49 D. From detection to imaging 59 E. Experimental demonstration 72 F. On observation of phase objects 86 IV. Dissemination and outreach 90 V. Conclusion 92 References 95 1 I. THE PROPOSED RESEARCH The NIAC Ghost Imaging of Space Objects research program has been carried out at the Jet Propulsion Laboratory, Caltech. The program consisted of Phase I (October 2011 to September 2012) and Phase II (October 2012 to September 2014). The research team consisted of Drs. Dmitry Strekalov (PI), Baris Erkmen, Igor Kulikov and Nan Yu. The team members acknowledge stimulating discussions with Drs. Leonidas Moustakas, Andrew Shapiro-Scharlotta, Victor Vilnrotter, Michael Werner and Paul Goldsmith of JPL; Maria Chekhova and Timur Iskhakov of Max Plank Institute for Physics of Light, Erlangen; Paul Nu˜nez of Coll`ege de France & Observatoire de la Cˆote d’Azur; and technical support from Victor White and Pierre Echternach of JPL. -
Mètodes De Detecció I Anàlisi D'exoplanetes
MÈTODES DE DETECCIÓ I ANÀLISI D’EXOPLANETES Rubén Soussé Villa 2n de Batxillerat Tutora: Dolors Romero IES XXV Olimpíada 13/1/2011 Mètodes de detecció i anàlisi d’exoplanetes . Índex - Introducció ............................................................................................. 5 [ Marc Teòric ] 1. L’Univers ............................................................................................... 6 1.1 Les estrelles .................................................................................. 6 1.1.1 Vida de les estrelles .............................................................. 7 1.1.2 Classes espectrals .................................................................9 1.1.3 Magnitud ........................................................................... 9 1.2 Sistemes planetaris: El Sistema Solar .............................................. 10 1.2.1 Formació ......................................................................... 11 1.2.2 Planetes .......................................................................... 13 2. Planetes extrasolars ............................................................................ 19 2.1 Denominació .............................................................................. 19 2.2 Història dels exoplanetes .............................................................. 20 2.3 Mètodes per detectar-los i saber-ne les característiques ..................... 26 2.3.1 Oscil·lació Doppler ........................................................... 27 2.3.2 Trànsits -
Archival VLT/Naco Multiplicity Investigation of Exoplanet Host Stars J
Astronomy & Astrophysics manuscript no. final_version c ESO 2018 November 27, 2018 Archival VLT/NaCo multiplicity investigation of exoplanet host stars J. Dietrich1; 2 and C. Ginski1; 3 1 Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden, The Netherlands e-mail: [email protected] 2 Harvard University, Cambridge, MA 02138, United States 3 Anton Pannekoek Institute for Astronomy, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands Received June XX, 2017; accepted YYY ABSTRACT Context. The influence of stellar multiplicity on planet formation is not yet well determined. Most planets are found using indirect detection methods via the small radial velocity or photometric variations of the primary star. These indirect detection methods are not sensitive to wide stellar companions. High-resolution imaging is thus needed to identify potential (sub)stellar companions to these stars. Aims. In this study we aim to determine the (sub)stellar multiplicity status of exoplanet host stars, that were not previously investigated for stellar multiplicity in the literature. For systems with non-detections we provide detailed detection limits to make them accessible for further statistical analysis. Methods. For this purpose we have employed previously unpublished high-resolution imaging data taken with VLT/NACO in a wide variety of different scientific programs and publicly accessible in the ESO archive. We used astrometric and theoretical population synthesis to determine whether detected companion candidates are likely to be bound or are merely chance-projected background objects. Results. We provide detailed detection limits for 39 systems and investigate 29 previously unknown companion candidates around five systems. -
STATISTICS of LONG PERIOD GAS GIANT PLANETS in KNOWN PLANETARY SYSTEMS Marta L
Accepted to ApJ: January 22, 2016 Preprint typeset using LATEX style emulateapj v. 5/2/11 STATISTICS OF LONG PERIOD GAS GIANT PLANETS IN KNOWN PLANETARY SYSTEMS Marta L. Bryan1, Heather A. Knutson2, Andrew W. Howard3, Henry Ngo2, Konstantin Batygin2, Justin R. Crepp4, B. J. Fulton3, Sasha Hinkley5, Howard Isaacson7 John A. Johnson6, Geoffry W. Marcy7 Jason T. Wright8 Accepted to ApJ: January 22, 2016 ABSTRACT We conducted a Doppler survey at Keck combined with NIRC2 K-band AO imaging to search for massive, long-period companions to 123 known exoplanet systems with one or two planets detected using the radial velocity (RV) method. Our survey is sensitive to Jupiter mass planets out to 20 AU for a majority of stars in our sample, and we report the discovery of eight new long-period planets, in addition to 20 systems with statistically significant RV trends indicating the presence of an outer companion beyond 5 AU. We combine our RV observations with AO imaging to determine the range of allowed masses and orbital separations for these companions, and account for variations in our sensitivity to companions among stars in our sample. We estimate the total occurrence rate of companions in our sample to be 52±5% over the range 1 - 20 MJup and 5 - 20 AU. Our data also suggest a declining frequency for gas giant planets in these systems beyond 3-10 AU, in contrast to earlier studies that found a rising frequency for giant planets in the range 0.01-3 AU. This suggests either that the frequency of gas giant planets peaks between 3-10 AU, or that outer companions in these systems have a different semi-major axis distribution than the overall gas giant planet population. -
Doctor of Philosophy
Study of Sun-like G Stars and Their Exoplanets Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy by Mr. SHASHANKA R. GURUMATH May, 2019 ABSTRACT By employing exoplanetary physical and orbital characteristics, aim of this study is to understand the genesis, dynamics, chemical abundance and magnetic field structure of Sun-like G stars and relationship with their planets. With reasonable constraints on selection of exoplanetary physical characteristics, and by making corrections for stellar rate of mass loss, a power law relationship between initial stellar mass and their exo- planetary mass is obtained that suggests massive stars harbor massive planets. Such a power law relationship is exploited to estimate the initial mass (1.060±0.006) M of the Sun for possible solution of “Faint young Sun paradox” which indeed indicates slightly higher mass compared to present mass. Another unsolved puzzle of solar system is angular momentum problem, viz., compare to Sun most of the angular momentum is concentrated in the solar system planets. By analyzing the exoplanetary data, this study shows that orbital angular momentum of Solar system planets is higher compared to orbital angular momentum of exoplanets. This study also supports the results of Nice and Grand Tack models that propose the idea of outward migration of Jovian planets during early history of Solar system formation. Furthermore, we have examined the influence of stellar metallicity on the host stars mass and exoplanetary physical and orbital characteristics that shows a non-linear relationship. Another important result is most of the planets in single planetary stellar systems are captured from the space and/or inward migration of planets might have played a dominant role in the final architecture of single planetary stellar systems. -
Planet Formation and Evolution: the Solar System and Extrasolar Planets
Planet Formation and Evolution: The Solar System and Extrasolar Planets 2nd to 6th March 2009, T¨ubingen, Germany Programme List of Posters Abstracts List of Participants 2 3 1 Programme Sunday, March 1 15:00 – 19:00 Registration (at Conference Center) 18:00 – 20:00 Welcome Reception (at Conference Center) Monday, March 2 8:15 – Registration (at Conference Center) 9:00 – 9:10 W. Kley Introduction, J. Jochum Welcome by the Vice Dean Session 1: The Beginning (Protoplanetary Disks) 9:10 – 9:50 S. Desch Star Formation Environment as a Control on Planetary Growth 9:50 – 10:10 S. Andrews High Spatial Resolution Constraints on Protoplanetary Disk Structure 10:10 – 10:30 A. Sicilia-Aguilar Evolved Protoplanetary Disks: The Multiwavelength Picture 10:30 – 11:00 Coffee Break 11:00 – 11:20 S. Renard Milli-arcsecond Imaging of the Inner Regions of Proto- planetary Disks 11:20 – 11:40 S. H¨ugelmeyer 1D and 3D radiative transfer in protoplanetary disks 11:40 – 12:00 P. Weise Radial-velocity planet-search survey of stars with cir- cumstellar disks 12:00 – 14:00 Lunch Break Session 2: Physics and Chemistry of Disks 14:00 – 14:40 R. Klessen Formation and Evolution of Protostellar Disks in Star Clusters 14:40 – 15:20 L. Mayer Formation of giant planets via disk instability; current status and new prospects 15:20 – 15:40 D. Semenov Modeling and Observations of the Chemical Evolution in Protoplanetary Disks 15:40 – 16:40 Poster-Session and Coffee Break 16:40 – 17:00 F. Meru Self-gravitating disks with radiative transfer: their role in giant planet formation 17:00 – 17:20 G. -
Bayesian Analysis of the Radial Velocities of HD 11506 Reveals Another Planetary Companion Mikko Tuomi1,2? and Samuli Kotiranta2??
Astronomy & Astrophysics manuscript no. 1531ms c ESO 2021 August 23, 2021 Letter to the Editor Bayesian analysis of the radial velocities of HD 11506 reveals another planetary companion Mikko Tuomi1;2? and Samuli Kotiranta2?? 1 Department of Mathematics and Statistics, P.O.Box 68, FI-00014 University of Helsinki, Finland 2 Tuorla Observatory, Department of Physics and Astronomy, University of Turku, FI-21500, Piikki¨o,Finland Received xx.xx.xxxx / Accepted xx.xx.xxxx ABSTRACT Aims. We aim to demonstrate the efficiency of a Bayesian approach in analysing radial velocity data by reanalysing a set of radial velocity measurements. Methods. We present Bayesian analysis of a recently published set of radial velocity measurements known to contain the signal of one extrasolar planetary candidate, namely, HD 11506. The analysis is conducted using the Markov chain Monte Carlo method and the resulting distributions of orbital parameters are tested by performing direct integration of randomly selected samples with the Bulirsch-Stoer method. The magnitude of the stellar radial velocity variability, known as jitter, is treated as a free parameter with no assumptions about its magnitude. Results. We show that the orbital parameters of the planet known to be present in the data correspond to a different solution when the jitter is allowed to be a free parameter. We also show evidence of an additional candidate, a 0.8 MJup planet with period of about 0.5 yr in orbit around HD 11506. This second planet is inferred to be present with a high level of confidence. Key words. planetary systems { Methods: statistical { Techniques: radial velocities { Stars: individual: HD 11506 1. -
Determining the True Mass of Radial-Velocity Exoplanets with Gaia 9 Planet Candidates in the Brown-Dwarf/Stellar Regime and 27 Confirmed Planets
Astronomy & Astrophysics manuscript no. exoplanet_mass_gaia c ESO 2020 September 30, 2020 Determining the true mass of radial-velocity exoplanets with Gaia 9 planet candidates in the brown-dwarf/stellar regime and 27 confirmed planets F. Kiefer1; 2, G. Hébrard1; 3, A. Lecavelier des Etangs1, E. Martioli1; 4, S. Dalal1, and A. Vidal-Madjar1 1 Institut d’Astrophysique de Paris, Sorbonne Université, CNRS, UMR 7095, 98 bis bd Arago, 75014 Paris, France 2 LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, 5 place Jules Janssen, 92195 Meudon, France? 3 Observatoire de Haute-Provence, CNRS, Universiteé d’Aix-Marseille, 04870 Saint-Michel-l’Observatoire, France 4 Laboratório Nacional de Astrofísica, Rua Estados Unidos 154, 37504-364, Itajubá - MG, Brazil Submitted on 2020/08/20 ; Accepted for publication on 2020/09/24 ABSTRACT Mass is one of the most important parameters for determining the true nature of an astronomical object. Yet, many published exoplan- ets lack a measurement of their true mass, in particular those detected thanks to radial velocity (RV) variations of their host star. For those, only the minimum mass, or m sin i, is known, owing to the insensitivity of RVs to the inclination of the detected orbit compared to the plane-of-the-sky. The mass that is given in database is generally that of an assumed edge-on system (∼90◦), but many other inclinations are possible, even extreme values closer to 0◦ (face-on). In such case, the mass of the published object could be strongly underestimated by up to two orders of magnitude. -
Evidence for Enhanced Chromospheric Ca II H and K Emission in Stars with Close-In Extrasolar Planets
A&A 540, A82 (2012) Astronomy DOI: 10.1051/0004-6361/201118247 & c ESO 2012 Astrophysics Evidence for enhanced chromospheric Ca II H and K emission in stars with close-in extrasolar planets T. Krejcovᡠ1 and J. Budaj2 1 Department of Theoretical Physics and Astrophysics, Masaryk University, Kotlárskᡠ2, 61137 Brno, Czech Republic e-mail: [email protected] 2 Astronomical Institute, Slovak Academy of Sciences, 05960 Tatranská Lomnica, Slovak Republic e-mail: [email protected] Received 11 October 2011 / Accepted 13 February 2012 ABSTRACT Context. The planet-star interaction is manifested in many ways. It has been found that a close-in exoplanet causes small but mea- surable variability in the cores of a few lines in the spectra of several stars, which corresponds to the orbital period of the exoplanet. Stars with and without exoplanets may have different properties. Aims. The main goal of our study is to search for the influence that exoplanets might have on atmospheres of their host stars. Unlike the previous studies, we do not study changes in the spectrum of a host star or differences between stars with and without exoplanets. We aim to study a large number of stars with exoplanets and the current level of their chromospheric activity and to look for a possible correlation with the exoplanetary properties. Methods. To analyse the chromospheric activity of stars, we exploited our own and publicly available archival spectra, measured the equivalent widths of the cores of Ca II H and K lines, and used them to trace their activity. Subsequently, we searched for their dependence on the orbital parameters and the mass of the exoplanet. -
Radial Velocities from the N2K Project: 6 New Cold Gas Giant Planets Orbiting HD 55696, HD 98736, HD 148164, HD 203473, and HD 211810 Kristo Ment,1, 2 Debra A
Draft version September 6, 2018 Typeset using LATEX preprint style in AASTeX62 Radial velocities from the N2K Project: 6 new cold gas giant planets orbiting HD 55696, HD 98736, HD 148164, HD 203473, and HD 211810 Kristo Ment,1, 2 Debra A. Fischer,1 Gaspar Bakos,3 Andrew W. Howard,4 and Howard Isaacson5 1Department of Astronomy, Yale University, 52 Hillhouse Avenue, New Haven, CT 06511, USA 2Harvard Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA 3Department of Astrophysical Sciences, Princeton University, NJ 08544, USA 4Department of Astronomy, California Institute of Technology, Pasadena, CA 91125, USA 5Department of Astronomy, University of California, Berkeley, CA 94720, USA (Received February 15, 2018; Revised August 23, 2018; Accepted August 29, 2018) Submitted to AJ ABSTRACT The N2K planet search program was designed to exploit the planet-metallicity cor- relation by searching for gas giant planets orbiting metal-rich stars. Here, we present the radial velocity measurements for 378 N2K target stars that were observed with the HIRES spectrograph at Keck Observatory between 2004 and 2017. With this data set, we announce the discovery of six new gas giant exoplanets: a double-planet system or- biting HD 148164 (M sin i of 1.23 and 5.16 MJUP) and single planet detections around HD 55696 (M sin i = 3.87 MJUP), HD 98736 (M sin i= 2.33 MJUP), HD 203473 (M sin i = 7.8 MJUP), and HD 211810 (M sin i = 0.67 MJUP). These gas giant companions have orbital semi-major axes between 1.0 and 6.2 AU and eccentricities ranging from 0.13 to 0.71. -
Predictions of Planets for 586 Exosystems and a Method for Predicting Planets in Multi-Planetary Exosystems Valeri Beck
Predictions of planets for 586 exosystems and a method for predicting planets in multi-planetary exosystems Valeri Beck To cite this version: Valeri Beck. Predictions of planets for 586 exosystems and a method for predicting planets in multi- planetary exosystems. 2019. hal-02050412v4 HAL Id: hal-02050412 https://hal.archives-ouvertes.fr/hal-02050412v4 Preprint submitted on 7 Aug 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Predictions of planets for 586 exosystems and a method for predicting planets in multi-planetary exosystems Valeri Beck*1 *Alfa Carbon® Beck, Berlin, Germany ABSTRACT We have applied a model of planetary system formation in the field of a standing sound wave (the ‘SSW-Model’) to the prediction of planets in 586 multi-planetary exosystems (384 bi- planetary, 127 tri-planetary and 75 exosystems with four or more confirmed planets). We have verified our predictions using transit-like events from the NASA Threshold-Crossing Event (TCE) catalogue, finding that more than 80% of these events are included in our list of exoplanet predictions. We describe a method for predicting the periods and semi-major axes of additional planets for exosystems with two or more confirmed planets.