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2016 Publication Year 2021-04-23T14:32:39Z Acceptance in OA@INAF Age Consistency Between Exoplanet Hosts and Field Stars Title B
Publication Year 2016 Acceptance in OA@INAF 2021-04-23T14:32:39Z Title Age consistency between exoplanet hosts and field stars Authors Bonfanti, A.; Ortolani, S.; NASCIMBENI, VALERIO DOI 10.1051/0004-6361/201527297 Handle http://hdl.handle.net/20.500.12386/30887 Journal ASTRONOMY & ASTROPHYSICS Number 585 A&A 585, A5 (2016) Astronomy DOI: 10.1051/0004-6361/201527297 & c ESO 2015 Astrophysics Age consistency between exoplanet hosts and field stars A. Bonfanti1;2, S. Ortolani1;2, and V. Nascimbeni2 1 Dipartimento di Fisica e Astronomia, Università degli Studi di Padova, Vicolo dell’Osservatorio 3, 35122 Padova, Italy e-mail: [email protected] 2 Osservatorio Astronomico di Padova, INAF, Vicolo dell’Osservatorio 5, 35122 Padova, Italy Received 2 September 2015 / Accepted 3 November 2015 ABSTRACT Context. Transiting planets around stars are discovered mostly through photometric surveys. Unlike radial velocity surveys, photo- metric surveys do not tend to target slow rotators, inactive or metal-rich stars. Nevertheless, we suspect that observational biases could also impact transiting-planet hosts. Aims. This paper aims to evaluate how selection effects reflect on the evolutionary stage of both a limited sample of transiting-planet host stars (TPH) and a wider sample of planet-hosting stars detected through radial velocity analysis. Then, thanks to uniform deriva- tion of stellar ages, a homogeneous comparison between exoplanet hosts and field star age distributions is developed. Methods. Stellar parameters have been computed through our custom-developed isochrone placement algorithm, according to Padova evolutionary models. The notable aspects of our algorithm include the treatment of element diffusion, activity checks in terms of 0 log RHK and v sin i, and the evaluation of the stellar evolutionary speed in the Hertzsprung-Russel diagram in order to better constrain age. -
IAU Division C Working Group on Star Names 2019 Annual Report
IAU Division C Working Group on Star Names 2019 Annual Report Eric Mamajek (chair, USA) WG Members: Juan Antonio Belmote Avilés (Spain), Sze-leung Cheung (Thailand), Beatriz García (Argentina), Steven Gullberg (USA), Duane Hamacher (Australia), Susanne M. Hoffmann (Germany), Alejandro López (Argentina), Javier Mejuto (Honduras), Thierry Montmerle (France), Jay Pasachoff (USA), Ian Ridpath (UK), Clive Ruggles (UK), B.S. Shylaja (India), Robert van Gent (Netherlands), Hitoshi Yamaoka (Japan) WG Associates: Danielle Adams (USA), Yunli Shi (China), Doris Vickers (Austria) WGSN Website: https://www.iau.org/science/scientific_bodies/working_groups/280/ WGSN Email: [email protected] The Working Group on Star Names (WGSN) consists of an international group of astronomers with expertise in stellar astronomy, astronomical history, and cultural astronomy who research and catalog proper names for stars for use by the international astronomical community, and also to aid the recognition and preservation of intangible astronomical heritage. The Terms of Reference and membership for WG Star Names (WGSN) are provided at the IAU website: https://www.iau.org/science/scientific_bodies/working_groups/280/. WGSN was re-proposed to Division C and was approved in April 2019 as a functional WG whose scope extends beyond the normal 3-year cycle of IAU working groups. The WGSN was specifically called out on p. 22 of IAU Strategic Plan 2020-2030: “The IAU serves as the internationally recognised authority for assigning designations to celestial bodies and their surface features. To do so, the IAU has a number of Working Groups on various topics, most notably on the nomenclature of small bodies in the Solar System and planetary systems under Division F and on Star Names under Division C.” WGSN continues its long term activity of researching cultural astronomy literature for star names, and researching etymologies with the goal of adding this information to the WGSN’s online materials. -
AMD-Stability and the Classification of Planetary Systems
A&A 605, A72 (2017) DOI: 10.1051/0004-6361/201630022 Astronomy c ESO 2017 Astrophysics& AMD-stability and the classification of planetary systems? J. Laskar and A. C. Petit ASD/IMCCE, CNRS-UMR 8028, Observatoire de Paris, PSL, UPMC, 77 Avenue Denfert-Rochereau, 75014 Paris, France e-mail: [email protected] Received 7 November 2016 / Accepted 23 January 2017 ABSTRACT We present here in full detail the evolution of the angular momentum deficit (AMD) during collisions as it was described in Laskar (2000, Phys. Rev. Lett., 84, 3240). Since then, the AMD has been revealed to be a key parameter for the understanding of the outcome of planetary formation models. We define here the AMD-stability criterion that can be easily verified on a newly discovered planetary system. We show how AMD-stability can be used to establish a classification of the multiplanet systems in order to exhibit the planetary systems that are long-term stable because they are AMD-stable, and those that are AMD-unstable which then require some additional dynamical studies to conclude on their stability. The AMD-stability classification is applied to the 131 multiplanet systems from The Extrasolar Planet Encyclopaedia database for which the orbital elements are sufficiently well known. Key words. chaos – celestial mechanics – planets and satellites: dynamical evolution and stability – planets and satellites: formation – planets and satellites: general 1. Introduction motion resonances (MMR, Wisdom 1980; Deck et al. 2013; Ramos et al. 2015) could justify the Hill-type criteria, but the The increasing number of planetary systems has made it nec- results on the overlap of the MMR island are valid only for close essary to search for a possible classification of these planetary orbits and for short-term stability. -
The Relative Distance Between the Clusters of Galaxies A2634 And
The Relative Distance between the Clusters of Galaxies A2634 and Coma 1 Marco Scodeggio, Riccardo Giovanelli and Martha P. Haynes Center for Radiophysics and Space Research and National Astronomy and Ionosphere Center, Cornell University, Ithaca, NY 14853 scodeggi, riccardo, [email protected] ABSTRACT The Tully-Fisher (TF) and Fundamental Plane (FP) relations are used to obtain two independent estimates of the relative distance between the clusters A2634 and Coma. Previously published studies of A2634 showed a large discrepancy between the distance estimates obtained with the TF and the Dn − σ relations, questioning the reliability of redshift-independent distances obtained using these relations. Because of the importance of this issue, we have obtained new distance estimates for A2634, based on much larger samples than previously used, and selected according to rigorous membership criteria. New I band CCD photometry for 175 galaxies, new 21 cm observations of 11 galaxies, and new velocity dispersion measurements for 62 galaxies are used together with previously published data in building these samples. As part of a larger project to compare the TF and FP distance-scales, we have obtained a new FP template using for the first time I band photometry. The template is derived using a sample of 109 E and S0 galaxies that are members of the Coma cluster. Its parameters are in very good agreement with recent determinations of the FP obtained at shorter wavelengths. The uncertainty with which the FP can provide peculiar velocity estimates for single galaxies is ≃0.43 mag in the distance modulus, or 20% of the distance. -
Determining the True Mass of Radial-Velocity Exoplanets with Gaia F
Determining the true mass of radial-velocity exoplanets with Gaia F. Kiefer, G. Hébrard, A. Lecavelier Des Etangs, E. Martioli, S. Dalal, A. Vidal-Madjar To cite this version: F. Kiefer, G. Hébrard, A. Lecavelier Des Etangs, E. Martioli, S. Dalal, et al.. Determining the true mass of radial-velocity exoplanets with Gaia: Nine planet candidates in the brown dwarf or stellar regime and 27 confirmed planets. Astronomy and Astrophysics - A&A, EDP Sciences, 2021, 645, pp.A7. 10.1051/0004-6361/202039168. hal-03085694 HAL Id: hal-03085694 https://hal.archives-ouvertes.fr/hal-03085694 Submitted on 21 Dec 2020 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. A&A 645, A7 (2021) Astronomy https://doi.org/10.1051/0004-6361/202039168 & © F. Kiefer et al. 2020 Astrophysics Determining the true mass of radial-velocity exoplanets with Gaia Nine planet candidates in the brown dwarf or 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 -
U.S. Department of Energy Human Genome 1991-92 Program Report
Please address queries on this publication to: Human Genome Program U.S. Department of Energy Office of Health and Environmental Research ER-72 GTN Washington, DC 20585 301/903-6488, Fax: 301/903-5051 Internet: "drell@ mailgw.er.doe.gov" Human Genome Management Information System Oak Ridge National Laboratory P.O. Box 2008 Oak Ridge, TN 37831 -6050 615/576-6669, Fax: 615/574-9888 BITNET: "bkq@ornlstc" Internet: "[email protected]" This report has been reproduced directly from the best obtainable copy. Available to DOE and DOE contractors from the Office of Scientific and Technical Information; P.O. Box 62; Oak Ridge, TN 37831 . Price information: 615/576-8401 . Available to the public from the National Technical Information Service; U.S. Department of Commerce; 5285 Port Royal Road; Springfield, VA 22161 . DOE/ER-0544P uman enome 1991-92 Program Report Date Published: June 1992 U.S. Department of Energy Office of Energy Research Office of Health and Environmental Research Washington, D.C. 20585 Major Events in the Development of the DOE Human Genome Program Meeting held in Santa Fe, New Mexico, to explore Human Genome Initiative feasibility DOE Human Genome Initiative announced I Pilot projects pursued at national laboratories: physical mapping, informatics, and development of critical resources and technologies lor genomic analysis HERAC recommendations made for the Human Genome Initiative First interagency workshop held on genomic resources and informatics LBL and LANL designated as human genome centers I First management and program plans -
Extrasolar Planets in Stellar Multiple Systems
Astronomy & Astrophysics manuscript no. exoplanets˙binaries˙final˙rn © ESO 2012 April 24, 2012 Extrasolar planets in stellar multiple systems T. Roell1, R. Neuh¨auser1, A. Seifahrt1,2,3, and M. Mugrauer1 1 Astrophysical Institute and University Observatory Jena, Schillerg¨aßchen 2, 07745 Jena, Germany e-mail: [email protected] 2 Physics Department, University of California, Davis, CA 95616, USA 3 Department of Astronomy and Astrophysics, University of Chicago, IL 60637, USA Received ...; accepted ... ABSTRACT Aims. Analyzing exoplanets detected by radial velocity (RV) or transit observations, we determine the multiplicity of exoplanet host stars in order to study the influence of a stellar companion on the properties of planet candidates. Methods. Matching the host stars of exoplanet candidates detected by radial velocity or transit observations with online multiplicity catalogs in addition to a literature search, 57 exoplanet host stars are identified having a stellar companion. Results. The resulting multiplicity rate of at least 12 % for exoplanet host stars is about four times smaller than the multiplicity of solar like stars in general. The mass and the number of planets in stellar multiple systems depend on the separation between their host star and its nearest stellar companion, e.g. the planetary mass decreases with an increasing stellar separation. We present an updated overview of exoplanet candidates in stellar multiple systems, including 15 new systems (compared to the latest summary from 2009). Key words. extrasolar planets – stellar multiple systems – planet formation 1. Introduction in Mugrauer & Neuh¨auser (2009), these studies found 44 stel- lar companions around stars previously not known to be mul- More than 700 extrasolar planet (exoplanet) candidates were dis- tiple, which results in a multiplicity rate of about 17 %, while covered so far (Schneider et al. -
Analytic Stability Maps of Unknown Exoplanet Companions for Imaging Prioritization
Bachelor's degree thesis ANALYTIC STABILITY MAPS OF UNKNOWN EXOPLANET COMPANIONS FOR IMAGING PRIORITIZATION Carlos Gasc´on Alvarez´ Advised by Dmitry Savransky (Cornell University) Miquel Sureda (UPC) In partial fulfillment of the requirements for the Bachelor's Degree in Mathematics Bachelor's Degree in Aerospace Technology Engineering July 2019 ABSTRACT Identifying which systems are more likely to host an imageable planet can play an important role in the construction of an optimized target list for future direct imaging missions, such as the planned technology demonstration for the Wide Field Infrared Survey Telescope (WFIRST). For single-planet systems, the presence of an already detected exoplanet can severely restrict the target's stable region and should therefore be considered when searching for unknown companions. To do so, we first analyze the performance and robustness of several two-planet stability criteria by comparing them with long-term numerical simulations. We then derive the necessary formulation for the computation of (a, R) analytic stability maps, which can be used in conjunction with depth- of-search grids in order to define the stable-imageable region of a system. The dynamically stable completeness (i.e., the expected number of imageable and stable planets) can then be calculated via convolution with the selected occurrence grid, obtaining a metric that can be directly compared for imaging prioritization. Applying this procedure to all the currently known single-planet systems within a distance of 50 pc, we construct a ranked target list based on the WFIRST CGI's predicted performance and SAG13 occurrence rates. Keywords| numerical simulations - analytic stability maps - dynamical evolution and stability - direct imaging - exoplanets 1 CONTENTS 1 Introduction 3 2 Analytic Stability Criteria for Two-Planet Systems 4 2.1 Criteria Based on the Outer Pericenter to Inner Apocenter Ratio . -
Exomoon Habitability and Tidal Evolution in Low-Mass Star Systems
EXOMOON HABITABILITY AND TIDAL EVOLUTION IN LOW-MASS STAR SYSTEMS by Rhett R. Zollinger A dissertation submitted to the faculty of The University of Utah in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Physics Department of Physics and Astronomy The University of Utah December 2014 Copyright © Rhett R. Zollinger 2014 All Rights Reserved The University of Utah Graduate School STATEMENT OF DISSERTATION APPROVAL The dissertation of Rhett R. Zollinger has been approved by the following supervisory committee members: Benjamin C. Bromley Chair 07/08/2014 Date Approved John C. Armstrong Member 07/08/2014 Date Approved Bonnie K. Baxter Member 07/08/2014 Date Approved Jordan M. Gerton Member 07/08/2014 Date Approved Anil C. Seth Member 07/08/2014 Date Approved and by Carleton DeTar Chair/Dean of the Department/College/School o f _____________Physics and Astronomy and by David B. Kieda, Dean of The Graduate School. ABSTRACT Current technology and theoretical methods are allowing for the detection of sub-Earth sized extrasolar planets. In addition, the detection of massive moons orbiting extrasolar planets (“exomoons”) has become feasible and searches are currently underway. Several extrasolar planets have now been discovered in the habitable zone (HZ) of their parent star. This naturally leads to questions about the habitability of moons around planets in the HZ. Red dwarf stars present interesting targets for habitable planet detection. Compared to the Sun, red dwarfs are smaller, fainter, lower mass, and much more numerous. Due to their low luminosities, the HZ is much closer to the star than for Sun-like stars. -
Determining the True Mass of Radial-Velocity Exoplanets with Gaia Nine Planet Candidates in the Brown Dwarf Or Stellar Regime and 27 Confirmed Planets? F
A&A 645, A7 (2021) Astronomy https://doi.org/10.1051/0004-6361/202039168 & © F. Kiefer et al. 2020 Astrophysics Determining the true mass of radial-velocity exoplanets with Gaia Nine planet candidates in the brown dwarf or 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 e-mail: [email protected] 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, Université d’Aix-Marseille, 04870 Saint-Michel-l’Observatoire, France 4 Laboratório Nacional de Astrofísica, Rua Estados Unidos 154, 37504-364, Itajubá - MG, Brazil Received 12 August 2020 / Accepted 24 September 2020 ABSTRACT Mass is one of the most important parameters for determining the true nature of an astronomical object. Yet, many published exoplanets lack a measurement of their true mass, in particular those detected as a result of radial-velocity (RV) variations of their host star. For those examples, 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 databases 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 a case, the mass of the published object could be strongly underestimated by up to two orders of magnitude. -
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. -
Chromospheric Activity Catalogue of 4454 Cool Stars Questioning the Active Branch of Stellar Activity Cycles? S
A&A 616, A108 (2018) Astronomy https://doi.org/10.1051/0004-6361/201629518 & © ESO 2018 Astrophysics Chromospheric activity catalogue of 4454 cool stars Questioning the active branch of stellar activity cycles? S. Boro Saikia1,2, C. J. Marvin1, S. V. Jeffers1, A. Reiners1, R. Cameron3, S. C. Marsden4, P. Petit5,6, J. Warnecke3, and A. P. Yadav1 1 Institut für Astrophysik, Georg-August-Universität Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen, Germany e-mail: [email protected] 2 Institut für Astrophysik, Universität Wien, Türkenschanzstrasse 17, 1180 Vienna, Austria 3 Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany 4 University of Southern Queensland, Computational Engineering and Science Research Centre, Toowoomba 4350, Australia 5 CNRS, Institut de Recherche en Astrophysique et Planétologie, 14 Avenue Edouard Belin, 31400 Toulouse, France 6 Université de Toulouse, UPS-OMP, Institut de Recherche en Astrophysique et Planétologie, Toulouse, France Received 11 August 2016 / Accepted 8 February 2018 ABSTRACT Context. Chromospheric activity monitoring of a wide range of cool stars can provide valuable information on stellar magnetic activ- ity and its dependence on fundamental stellar parameters such as effective temperature and rotation. Aims. We compile a chromospheric activity catalogue of 4454 cool stars from a combination of archival HARPS spectra and multiple other surveys, including the Mount Wilson data that have recently been released by the NSO. We explore the variation in chromo- spheric activity of cool stars along the main sequence for stars with different effective temperatures. Additionally, we also perform an activity-cycle period search and investigate its relation with rotation.