1. A seismic and gravitationally bound double star observed by Kepler
- Author
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Tiago L. Campante, Mark E. Everett, Warrick H. Ball, T. Appourchaux, H. M. Antia, Sergei V. Vorontsov, William J. Chaplin, Kuldeep Verma, Josefina Montalbán, David R. Ciardi, Clara Régulo, Yveline Lebreton, Patrick Gaulme, Laurent Gizon, Steve B. Howell, Rafael A. García, Luca Fossati, Andrea Miglio, Elliott P. Horch, O. L. Creevey, Guy R. Davies, Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), and Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS)
- Subjects
solar-type [stars] ,Stellar mass ,Metallicity ,Double star ,Astrophysics ,asteroseismology ,Asteroseismology ,general [binaries] ,Binary star ,LINE-DATA-BASE ,stars: evolution ,MAIN-SEQUENCE ,Physics ,SOLAR-TYPE STARS ,Astronomy ,Astronomy and Astrophysics ,stars: solar-type ,Astrometry ,ASTROMETRIC MEASUREMENTS ,EQUATION-OF-STATE ,RED-GIANT BRANCH ,binaries ,stars ,evolution ,solar-type ,astrometry ,Stars ,binaries: general ,Space and Planetary Science ,Stellar mass loss ,evolution [stars] ,SPECKLE OBSERVATIONS ,STELLAR OSCILLATION FREQUENCIES ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,SPACE-BASED PHOTOMETRY ,BINARY STARS - Abstract
International audience; Context. Solar-like oscillations have been observed by Kepler and CoRoT in many solar-type stars, thereby providing a way to probe stars using asteroseismology.Aims. The derivation of stellar parameters has usually been done with single stars. The aim of the paper is to derive the stellar parameters of a double-star system (HIP 93511), for which an interferometric orbit has been observed along with asteroseismic measurements.Methods. We used a time series of nearly two years of data for the double star to detect the two oscillation-mode envelopes that appear in the power spectrum. Using a new scaling relation based on luminosity, we derived the radius and mass of each star. We derived the age of each star using two proxies: one based upon the large frequency separation and a new one based upon the small frequency separation. Using stellar modelling, the mode frequencies allowed us to derive the radius, the mass, and the age of each component. In addition, speckle interferometry performed since 2006 has enabled us to recover the orbit of the system and the total mass of the system.Results. From the determination of the orbit, the total mass of the system is 2.34-0.33+0.45 M⊙. The total seismic mass using scaling relations is 2.47 ± 0.07 M⊙. The seismic age derived using the new proxy based upon the small frequency separation is 3.5 ± 0.3 Gyr. Based on stellar modelling, the mean common age of the system is 2.7–3.9 Gyr. The mean total seismic mass of the system is 2.34–2.53 M⊙ consistent with what we determined independently with the orbit. The stellar models provide the mean radius, mass, and age of the stars as RA = 1.82−1.87R⊙, MA = 1.25−1.39 M⊙, AgeA = 2.6–3.5 Gyr; RB = 1.22−1.25 R⊙, MB = 1.08−1.14 M⊙, AgeB = 3.35–4.21 Gyr. The models provide two sets of values for Star A: [1.25–1.27] M⊙ and [1.34–1.39] M⊙. We detect a convective core in Star A, while Star B does not have any. For the metallicity of the binary system of Z ≈ 0.02, we set the limit between stars having a convective core in the range [1.14–1.25] M⊙.
- Published
- 2015
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