[en] We report the observations of a main-sequence star, HD 42618 (T[SUB]eff[/SUB] = 5765 K, G3V) by the space telescope CoRoT. This is the closest star to the Sun ever observed by CoRoT in term of its fundamental parameters. Using a preliminary version of CoRoT light curves of HD 42618, p modes are detected around 3.2 mHz associated to l = 0, 1 and 2 modes with a large spacing of 142 μHz. Various methods are then used to derive the mass and radius of this star (scaling relations from solar values as well as comparison between theoretical and observationnal frequencies) giving values in the range of (0.80 - 1.02)M[SUB]solar[/SUB] and (0.91 - 1.01)R[SUB]solar[/SUB]. A preliminary analysis of l = 0 and 1 modes allows us also to study the amount of penetrative convection at the base of the convective envelope.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Barban, C.; LESIA, CNRS UMR 8109, Observatoire de Paris, Université Pierre et Marie Curie, Université Denis Diderot, France
Deheuvels, S.; CNRS, Institut de Recherche en Astrophysique et Planétologie, Toulouse, France ; Université de Toulouse, UPS-OMP, IRAP, France
Goupil, M. J.; LESIA, CNRS UMR 8109, Observatoire de Paris, Université Pierre et Marie Curie, Université Denis Diderot, France
Lebreton, Y.; Observatoire de Paris, GEPI, CNRS UMR 8111, France ; Institut de Physique de Rennes, Université de Rennes 1, CNRS UMR 6251, France
Mathur, S.; High Altitude Observatory, NCAR, PO Box 3000, Boulder, CO 80307, USA ; Laboratoire AIM, CEA/DSM-CNRS-Université Paris Diderot ; IRFU/SAp, Centre de Saclay, France
Michel, E.
Morel, Thierry ; Université de Liège - ULiège > GAPHE : Astrophysique observationnelle (sol et espace)
Ballot, J.; CNRS, Institut de Recherche en Astrophysique et Planétologie, Toulouse, France ; Université de Toulouse, UPS-OMP, IRAP, France
Baudin, F.; Institut d'Astrophysique Spatiale, UMR8617, CNRS, Université Paris XI, France
Belkacem, K.; LESIA, CNRS UMR 8109, Observatoire de Paris, Université Pierre et Marie Curie, Université Denis Diderot, France
Benomar, O.; Sydney Institute for Astronomy (SIfA), School of Physics, University of Sydney, Australia
Boumier, P.; Institut d'Astrophysique Spatiale, UMR8617, CNRS, Université Paris XI, France
Davies, G. R.; Laboratoire AIM, CEA/DSM-CNRS-Université Paris Diderot ; IRFU/SAp, Centre de Saclay, France ; School of Physics and Astronomy, University of Birmingham, UK
García, R. A.; Laboratoire AIM, CEA/DSM-CNRS-Université Paris Diderot ; IRFU/SAp, Centre de Saclay, France
Hall, M. P.; Jeremiah Horrocks Institute of Astrophysics, University of Central Lancashire, Preston PR1 2HE, UK
Mosser, B.; LESIA, CNRS UMR 8109, Observatoire de Paris, Université Pierre et Marie Curie, Université Denis Diderot, France
Poretti, E.; INAF Osservatorio Astronomico di Brera, Merate, Italy
Régulo, C.; Instituto de Astrofísica de Canarias, Tenerife, Spain ; Departamento de Astrofísica, Universidad de La Laguna, Tenerife, Spain
Roxburgh, I.; Queen Mary University of London, Astronomy Unit, UK
Samadi, R.; LESIA, CNRS UMR 8109, Observatoire de Paris, Université Pierre et Marie Curie, Université Denis Diderot, France
Verner, G.; Queen Mary University of London, Astronomy Unit, UK
