CURRICULUM VITAE Travis S. Metcalfe White Dwarf Research
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Characterizing Two Solar-Type Kepler Subgiants with Asteroseismology: Kic 10920273 and Kic 11395018
The Astrophysical Journal, 763:49 (10pp), 2013 January 20 doi:10.1088/0004-637X/763/1/49 C 2013. The American Astronomical Society. All rights reserved. Printed in the U.S.A. CHARACTERIZING TWO SOLAR-TYPE KEPLER SUBGIANTS WITH ASTEROSEISMOLOGY: KIC 10920273 AND KIC 11395018 G. Doganˇ 1,2,3, T. S. Metcalfe1,3,4, S. Deheuvels3,5,M.P.DiMauro6, P. Eggenberger7, O. L. Creevey8,9,10, M. J. P. F. G. Monteiro11, M. Pinsonneault3,12, A. Frasca13, C. Karoff2, S. Mathur1,S.G.Sousa11,I.M.Brandao˜ 11, T. L. Campante11,14, R. Handberg2, A. O. Thygesen2,15, K. Biazzo16,H.Bruntt2, E. Niemczura17, T. R. Bedding18, W. J. Chaplin3,14, J. Christensen-Dalsgaard2,3,R.A.Garc´ıa3,19, J. Molenda-Zakowicz˙ 17, D. Stello18, J. L. Van Saders3,12, H. Kjeldsen2, M. Still20, S. E. Thompson21, and J. Van Cleve21 1 High Altitude Observatory, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307, USA; [email protected] 2 Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C, Denmark 3 Kavli Institute for Theoretical Physics, Kohn Hall, University of California, Santa Barbara, CA 93106, USA 4 Space Science Institute, Boulder, CO 80301, USA 5 Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520-8101, USA 6 INAF-IAPS, Istituto di Astrofisica e Planetologia Spaziali, Via del Fosso del Cavaliere 100, I-00133 Roma, Italy 7 Geneva Observatory, University of Geneva, Maillettes 51, 1290 Sauverny, Switzerland 8 Universite´ de Nice, Laboratoire Cassiopee,´ CNRS UMR 6202, Observatoire de la Coteˆ d’Azur, BP 4229, F-06304 Nice Cedex 4, France 9 IAC Instituto de Astrof´ısica de Canarias, C/V´ıa Lactea´ s/n, E-38200 Tenerife, Spain 10 Universidad de La Laguna, Avda. -
![Arxiv:1909.05961V1 [Astro-Ph.SR] 12 Sep 2019](https://docslib.b-cdn.net/cover/1730/arxiv-1909-05961v1-astro-ph-sr-12-sep-2019-141730.webp)
Arxiv:1909.05961V1 [Astro-Ph.SR] 12 Sep 2019
Draft version September 16, 2019 Typeset using LATEX twocolumn style in AASTeX62 TESS ASTEROSEISMOLOGY OF THE KNOWN RED-GIANT HOST STARS HD 212771 AND HD 203949 Tiago L. Campante,1, 2, 3 Enrico Corsaro,4 Mikkel N. Lund,5, 3 Beno^ıt Mosser,6 Aldo Serenelli,7, 8, 3 Dimitri Veras,9, 10, 3, ∗ Vardan Adibekyan,1 H. M. Antia,11 Warrick Ball,12, 5 Sarbani Basu,13 Timothy R. Bedding,14, 5, 3 Diego Bossini,1 Guy R. Davies,12, 5 Elisa Delgado Mena,1 Rafael A. Garc´ıa,15, 16 Rasmus Handberg,5 Marc Hon,17 Stephen R. Kane,18 Steven D. Kawaler,19, 3 James S. Kuszlewicz,20, 5 Miles Lucas,19 Savita Mathur,21, 22 Nicolas Nardetto,23 Martin B. Nielsen,12, 5, 24 Marc H. Pinsonneault,25, 3 Sabine Reffert,26 V´ıctor Silva Aguirre,5 Keivan G. Stassun,27, 28 Dennis Stello,17, 14, 5, 3 Stephan Stock,26 Mathieu Vrard,1 Mutlu Yıldız,29 William J. Chaplin,12, 5, 3 Daniel Huber,30, 3 Jacob L. Bean,31 Zeynep C¸elik Orhan,29 Margarida S. Cunha,1, 2 Jørgen Christensen-Dalsgaard,5, 3 Hans Kjeldsen,5, 32 Travis S. Metcalfe,33, 20 Andrea Miglio,12, 5 Mario´ J. P. F. G. Monteiro,1, 2 Benard Nsamba,1 Sibel Ortel¨ ,29 Filipe Pereira,1 Sergio´ G. Sousa,1, 2 Maria Tsantaki,1 and Margaret C. Turnbull34 1Instituto de Astrof´ısica e Ci^enciasdo Espa¸co,Universidade do Porto, Rua das Estrelas, 4150-762 Porto, Portugal 2Departamento de F´ısica e Astronomia, Faculdade de Ci^enciasda Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal 3Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106-4030, USA 4INAF | Osservatorio Astrofisico di Catania, via S. -
Magnetism, Dynamo Action and the Solar-Stellar Connection
Living Rev. Sol. Phys. (2017) 14:4 DOI 10.1007/s41116-017-0007-8 REVIEW ARTICLE Magnetism, dynamo action and the solar-stellar connection Allan Sacha Brun1 · Matthew K. Browning2 Received: 23 August 2016 / Accepted: 28 July 2017 © The Author(s) 2017. This article is an open access publication Abstract The Sun and other stars are magnetic: magnetism pervades their interiors and affects their evolution in a variety of ways. In the Sun, both the fields themselves and their influence on other phenomena can be uncovered in exquisite detail, but these observations sample only a moment in a single star’s life. By turning to observa- tions of other stars, and to theory and simulation, we may infer other aspects of the magnetism—e.g., its dependence on stellar age, mass, or rotation rate—that would be invisible from close study of the Sun alone. Here, we review observations and theory of magnetism in the Sun and other stars, with a partial focus on the “Solar-stellar connec- tion”: i.e., ways in which studies of other stars have influenced our understanding of the Sun and vice versa. We briefly review techniques by which magnetic fields can be measured (or their presence otherwise inferred) in stars, and then highlight some key observational findings uncovered by such measurements, focusing (in many cases) on those that offer particularly direct constraints on theories of how the fields are built and maintained. We turn then to a discussion of how the fields arise in different objects: first, we summarize some essential elements of convection and dynamo theory, includ- ing a very brief discussion of mean-field theory and related concepts. -
The Exoplanet-Host Star Ι Horologii: an Evaporated Member of the Primordial Hyades Cluster
A&A 482, L5–L8 (2008) Astronomy DOI: 10.1051/0004-6361:20079342 & c ESO 2008 Astrophysics Letter to the Editor The exoplanet-host star ι Horologii: an evaporated member of the primordial Hyades cluster S. Vauclair1,M.Laymand1, F. Bouchy2, G. Vauclair1,A.HuiBonHoa1, S. Charpinet1, and M. Bazot3 1 Laboratoire d’Astrophysique de Toulouse-Tarbes, CNRS, Université de Toulouse, 14 Av. Ed. Belin, 31400 Toulouse, France e-mail: [email protected] 2 Institut d’Astrophysique de Paris, 75014 Paris, France 3 Centro de Astrophysica da Universidade do Porto, Porto, Portugal Received 30 December 2007 / Accepted 4 March 2008 ABSTRACT Aims. We show that the exoplanet-host star iota Horologii, alias HD 17051, which belongs to the so-called Hyades stream, was formed within the primordial Hyades stellar cluster and has evaporated towards its present location, 40 pc away. Methods. This result has been obtained unambiguously by studying the acoustic oscillations of this star, using the HARPS spectrom- eter in La Silla Observatory (ESO, Chili). Results. Besides the fact that ι Hor belongs to the Hyades stream, we give evidence that it has the same metallicity, helium abun- dance, and age as the other stars of the Hyades cluster. They were formed together, at the same time, in the same primordial cloud. Conclusions. This result has strong implications for theories of stellar formation. It also indicates that the observed overmetallicity of this exoplanet-host star, about twice that of the Sun, is original and not caused by planet accretion during the formation of the planetary system. Key words. -
Asteroseismology Notes
2 observed pulsations • operate on the dynamical time scale Asteroseismology • accessible on convenient time scale • probe global and local structure Steve Kawaler • periods change on ‘evolutionary’ time scale Iowa State University (thermal or nuclear) - depend on global properties • amplitudes change on ~ ‘local’ thermal time scale 3 4 dynamical stability a more complex example: a star • “stable” configuration represents a stable mean configuration • multiple oscillation modes • on short time scale, oscillations occur, but the • radial modes - enumerated by number of mean value is fixed on longer time scales nodes between center and surface • simple example: a pendulum (single mode) • most likely position - extrema • non-radial modes - nodes also across • mean position is at zero displacement surface of constant radius with no damping would oscillate forever • • modes frequencies determined by solution of • more complex example: a vibrating string the appropriate wave equation • multiple modes with different frequencies • enumerated by number of nodes 5 6 stability, damping, and driving Okay, start your engines... • PG 1159: light curve • zero energy change: what kind of star might this be? constant amplitude oscillation • • what kind of star can this not possibly be? • energy loss via pulsation: • what about the amplitude over the run? oscillation amplitude drops with time • PG 1336 light curve • if net energy input: • huh? what time scale(s) are involved amplitude increases with time • what kind of star (or stars)? (if properly phased) -
Planet Hunters1 (Fischer Et Al
draft version May 31, 2012 Planet Hunters: Assessing the Kepler Inventory of Short Period Planets Megan E. Schwamb1,2,3,Chris J. Lintott4,5, Debra A. Fischer6, Matthew J. Giguere6, Stuart Lynn5,4, Arfon M. Smith5,4, John M. Brewer6, Michael Parrish5, Kevin Schawinski2,3,7, and Robert J. Simpson4 [email protected] ABSTRACT We present the results from a search of data from the first 33.5 days of the Kepler science mission (Quarter 1) for exoplanet transits by the Planet Hunters citizen science project. Planet Hunters enlists members of the general public to visually identify tran- sits in the publicly released Kepler light curves via the World Wide Web. Over 24,000 volunteers reviewed the Kepler Quarter 1 data set. We examine the abundance of ≥ 2 R⊕ planets on short period (< 15 days) orbits based on Planet Hunters detections. We present these results along with an analysis of the detection efficiency of human classifiers to identify planetary transits including a comparison to the Kepler inventory of planet candidates. Although performance drops rapidly for smaller radii, ≥ 4 R⊕ Planet Hunters ≥ 85% efficient at identifying transit signals for planets with periods less than 15 days for the Kepler sample of target stars. Our high efficiency rate for simulated transits along with recovery of the majority of Kepler ≥4R⊕ planets suggest suggests the Kepler inventory of ≥4 R⊕ short period planets is nearly complete. Subject headings: Planets and satellites: detection-Planets and satellites: general 1. Introduction In the past nearly two decades, there has been an explosion in the number of known planets arXiv:1205.6769v1 [astro-ph.EP] 30 May 2012 orbiting stars beyond our own solar system, with over 700 extrasolar planets (exoplanets) known 1Yale Center for Astronomy and Astrophysics, Yale University,P.O. -
Jason A. Dittmann 51 Pegasi B Postdoctoral Fellow
Jason A. Dittmann 51 Pegasi b Postdoctoral Fellow Contact Massachusetts Institute of Technology MIT Kavli Institute: 37-438f 617-258-5928 (office) 70 Vassar St. 520-820-0928 (cell) Cambridge, MA 02139 [email protected] Education Harvard University, Cambridge, MA PhD, Astronomy and Astrophysics, May 2016 Advisor: David Charbonneau, PhD • University of Arizona, Tucson, AZ BS, Astronomy, Physics, May 2010 Advisor: Laird Close, PhD • Recent 51 Pegasi b Postdoctoral Fellow July 2017 – Present Research Earth and Planetary Science Department, MIT Positions Faculty Contact: Sara Seager Postdoctoral Researcher Feb 2017 – June 2017 Kavli Institute, MIT Supervisor: Sarah Ballard Postdoctoral Researcher July 2016 – Jan 2017 Center for Astrophysics, Harvard University Supervisor: David Charbonneau Research Assistant Sep 2010 – May 2016 Center for Astrophysics, Harvard University Advisors: David Charbonneau Publication 16 first and second authored publications Summary 22 additional co-authored publications 1 first-authored publication in Nature 1 co-authored publication in Nature Selected 51 Pegasi b Postdoctoral Fellowship 2017 – Present Awards and Pierce Fellowship 2010 – 2013 Honors Certificate of Distinction in Teaching 2012 Best Project Award, Physics Ugrd. Research Symp. 2009 Best Undergraduate Research (Steward Observatory) 2009 – 2010 Grants Principal Investigator, Hubble Space Telescope 2017, 10 orbits Awarded “Initial Reconaissance of a Transiting Rocky (maximum award) Planet in a Nearby M-Dwarf’s Habitable Zone” Principal Investigator, -
Lietuvos Mokslo Tarybos Pirmininkas Įsakymas Dėl Gamtos Mokslų Srities 2019 Metais Paskelbtų Ir Mokslo Ir Studijų Instituci
LIETUVOS MOKSLO TARYBOS PIRMININKAS ĮSAKYMAS DĖL GAMTOS MOKSLŲ SRITIES 2019 METAIS PASKELBTŲ IR MOKSLO IR STUDIJŲ INSTITUCIJŲ PATEIKTŲ VERTINTI MOKSLO DARBŲ FORMALIOJO ĮVERTINIMO APIBENDRINTŲ REZULTATŲ PATVIRTINIMO 2020 m. spalio 22 d. Nr. V-529 Vilnius Vadovaudamasis Kasmetinio universitetų ir mokslinių tyrimų institutų mokslinių tyrimų ir eksperimentinės plėtros ir meno veiklos vertinimo reglamento, patvirtinto Lietuvos Respublikos švietimo ir mokslo ministro 2017 m. spalio 4 d. įsakymu Nr. V-747 „Dėl kasmetinio universitetų ir mokslinių tyrimų institutų mokslinių tyrimų ir eksperimentinės plėtros ir meno veiklos vertinimo reglamento patvirtinimo“ (suvestinė redakcija nuo 2020-03- 04) nuostatomis ir Lietuvos mokslo ir studijų institucijų mokslinių tyrimų ir eksperimentinės plėtros bei meno veiklos vertinimo gairių, patvirtintų Lietuvos mokslo tarybos pirmininko 2018 m. birželio 15 d. įsakymu Nr. V-307 „Dėl Lietuvos mokslo ir studijų institucijų mokslinių tyrimų ir eksperimentinės plėtros bei meno veiklos vertinimo gairių patvirtinimo“ (suvestinė redakcija nuo 2020-05-14) 56 punktu, atsižvelgdamas į ekspertinio vertinimo išvadas ir Gamtos ir technikos mokslų komiteto 2020 m. spalio 5 d. siūlymą (posėdžio protokolo Nr. GTM-P-27), t v i r t i n u gamtos mokslų srities 2019 metais paskelbtų ir pateiktų vertinti mokslo darbų formaliojo įvertinimo rezultatus „Gamtos mokslų srities 2019 metais paskelbtų ir mokslo ir studijų institucijų pateiktų vertinti mokslo darbų formaliojo įvertinimo apibendrinti rezultatai“ (pridedama). Pirmininkas Romas Baronas Parengė Milda Jodinskienė 2020-10-20 PATVIRTINTA Lietuvos mokslo tarybos pirmininko 2020 m. spalio 22 d. įsakymu Nr. V-529 GAMTOS MOKSLŲ SRITIES 2019 METAIS PASKELBTŲ IR MOKSLO IR STUDIJŲ INSTITUCIJŲ PATEIKTŲ VERTINTI MOKSLO DARBŲ1 FORMALIOJO ĮVERTINIMO APIBENDRINTI REZULTATAI Mokslo Mokslo ir studijų Darbo Institucijoms Eil. -
A Search for Transiting Extrasolar Planets in the Open Cluster NGC 4755
ResearchOnline@JCU This file is part of the following reference: Jayawardene, Bandupriya S. (2015) A search for transiting extrasolar planets in the open cluster NGC 4755. DAstron thesis, James Cook University. Access to this file is available from: http://researchonline.jcu.edu.au/41511/ The author has certified to JCU that they have made a reasonable effort to gain permission and acknowledge the owner of any third party copyright material included in this document. If you believe that this is not the case, please contact [email protected] and quote http://researchonline.jcu.edu.au/41511/ A SEARCH FOR TRANSITING EXTRASOLAR PLANETS IN THE OPEN CLUSTER NGC 4755 by Bandupriya S. Jayawardene A thesis submitted in satisfaction of the requirements for the degree of Doctor of Astronomy in the Faculty of Science, Technology and Engineering June 2015 James Cook University Townsville - Australia i STATEMENT OF ACCESS I the undersigned, author of this work, understand that James Cook University will make this thesis available for use within the University Library and, via the Australian Digital Thesis network, for use elsewhere. I understand that, as an unpublished work, a thesis has significant protection under the Copyright Act and; I do not wish to place any further restriction on access to this work. 2 STATEMENT OF SOURCES DECLARATION I declare that this thesis is my own work and has not been submitted in any form for another degree or diploma at any University or other institution of tertiary education. Information derived from the published or unpublished work of others has been acknowledged in the text and list of references is given. -
Superflares and Giant Planets
Superflares and Giant Planets From time to time, a few sunlike stars produce gargantuan outbursts. Large planets in tight orbits might account for these eruptions Eric P. Rubenstein nvision a pale blue planet, not un- bushes to burst into flames. Nor will the lar flares, which typically last a fraction Elike the Earth, orbiting a yellow star surface of the planet feel the blast of ul- of an hour and release their energy in a in some distant corner of the Galaxy. traviolet light and x rays, which will be combination of charged particles, ul- This exercise need not challenge the absorbed high in the atmosphere. But traviolet light and x rays. Thankfully, imagination. After all, astronomers the more energetic component of these this radiation does not reach danger- have now uncovered some 50 “extra- x rays and the charged particles that fol- ous levels at the surface of the Earth: solar” planets (albeit giant ones). Now low them are going to create havoc The terrestrial magnetic field easily de- suppose for a moment something less when they strike air molecules and trig- flects the charged particles, the upper likely: that this planet teems with life ger the production of nitrogen oxides, atmosphere screens out the x rays, and and is, perhaps, populated by intelli- which rapidly destroy ozone. the stratospheric ozone layer absorbs gent beings, ones who enjoy looking So in the space of a few days the pro- most of the ultraviolet light. So solar up at the sky from time to time. tective blanket of ozone around this flares, even the largest ones, normally During the day, these creatures planet will largely disintegrate, allow- pass uneventfully. -
![Arxiv:0908.2624V1 [Astro-Ph.SR] 18 Aug 2009](https://docslib.b-cdn.net/cover/1870/arxiv-0908-2624v1-astro-ph-sr-18-aug-2009-1111870.webp)
Arxiv:0908.2624V1 [Astro-Ph.SR] 18 Aug 2009
Astronomy & Astrophysics Review manuscript No. (will be inserted by the editor) Accurate masses and radii of normal stars: Modern results and applications G. Torres · J. Andersen · A. Gim´enez Received: date / Accepted: date Abstract This paper presents and discusses a critical compilation of accurate, fun- damental determinations of stellar masses and radii. We have identified 95 detached binary systems containing 190 stars (94 eclipsing systems, and α Centauri) that satisfy our criterion that the mass and radius of both stars be known to ±3% or better. All are non-interacting systems, so the stars should have evolved as if they were single. This sample more than doubles that of the earlier similar review by Andersen (1991), extends the mass range at both ends and, for the first time, includes an extragalactic binary. In every case, we have examined the original data and recomputed the stellar parameters with a consistent set of assumptions and physical constants. To these we add interstellar reddening, effective temperature, metal abundance, rotational velocity and apsidal motion determinations when available, and we compute a number of other physical parameters, notably luminosity and distance. These accurate physical parameters reveal the effects of stellar evolution with un- precedented clarity, and we discuss the use of the data in observational tests of stellar evolution models in some detail. Earlier findings of significant structural differences between moderately fast-rotating, mildly active stars and single stars, ascribed to the presence of strong magnetic and spot activity, are confirmed beyond doubt. We also show how the best data can be used to test prescriptions for the subtle interplay be- tween convection, diffusion, and other non-classical effects in stellar models. -
![Arxiv:2006.10868V2 [Astro-Ph.SR] 9 Apr 2021 Spain and Institut D’Estudis Espacials De Catalunya (IEEC), C/Gran Capit`A2-4, E-08034 2 Serenelli, Weiss, Aerts Et Al](https://docslib.b-cdn.net/cover/3592/arxiv-2006-10868v2-astro-ph-sr-9-apr-2021-spain-and-institut-d-estudis-espacials-de-catalunya-ieec-c-gran-capit-a2-4-e-08034-2-serenelli-weiss-aerts-et-al-1213592.webp)
Arxiv:2006.10868V2 [Astro-Ph.SR] 9 Apr 2021 Spain and Institut D’Estudis Espacials De Catalunya (IEEC), C/Gran Capit`A2-4, E-08034 2 Serenelli, Weiss, Aerts Et Al
Noname manuscript No. (will be inserted by the editor) Weighing stars from birth to death: mass determination methods across the HRD Aldo Serenelli · Achim Weiss · Conny Aerts · George C. Angelou · David Baroch · Nate Bastian · Paul G. Beck · Maria Bergemann · Joachim M. Bestenlehner · Ian Czekala · Nancy Elias-Rosa · Ana Escorza · Vincent Van Eylen · Diane K. Feuillet · Davide Gandolfi · Mark Gieles · L´eoGirardi · Yveline Lebreton · Nicolas Lodieu · Marie Martig · Marcelo M. Miller Bertolami · Joey S.G. Mombarg · Juan Carlos Morales · Andr´esMoya · Benard Nsamba · KreˇsimirPavlovski · May G. Pedersen · Ignasi Ribas · Fabian R.N. Schneider · Victor Silva Aguirre · Keivan G. Stassun · Eline Tolstoy · Pier-Emmanuel Tremblay · Konstanze Zwintz Received: date / Accepted: date A. Serenelli Institute of Space Sciences (ICE, CSIC), Carrer de Can Magrans S/N, Bellaterra, E- 08193, Spain and Institut d'Estudis Espacials de Catalunya (IEEC), Carrer Gran Capita 2, Barcelona, E-08034, Spain E-mail: [email protected] A. Weiss Max Planck Institute for Astrophysics, Karl Schwarzschild Str. 1, Garching bei M¨unchen, D-85741, Germany C. Aerts Institute of Astronomy, Department of Physics & Astronomy, KU Leuven, Celestijnenlaan 200 D, 3001 Leuven, Belgium and Department of Astrophysics, IMAPP, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, the Netherlands G.C. Angelou Max Planck Institute for Astrophysics, Karl Schwarzschild Str. 1, Garching bei M¨unchen, D-85741, Germany D. Baroch J. C. Morales I. Ribas Institute of· Space Sciences· (ICE, CSIC), Carrer de Can Magrans S/N, Bellaterra, E-08193, arXiv:2006.10868v2 [astro-ph.SR] 9 Apr 2021 Spain and Institut d'Estudis Espacials de Catalunya (IEEC), C/Gran Capit`a2-4, E-08034 2 Serenelli, Weiss, Aerts et al.