[en] Context. The availability of asteroseismic constraints for a large sample of red giant stars from the CoRoT and Kepler missions paves the way for various statistical studies of the seismic properties of stellar populations. <BR /> Aims: We use a detailed spectroscopic study of 19 CoRoT red giant stars to compare theoretical stellar evolution models to observations of the open cluster NGC 6633 and field stars. <BR /> Methods: In order to explore the effects of rotation-induced mixing and thermohaline instability, we compare surface abundances of carbon isotopic ratio and lithium with stellar evolution predictions. These chemicals are sensitive to extra-mixing on the red giant branch. <BR /> Results: We estimate mass, radius, and distance for each star using the seismic constraints. We note that the Hipparcos and seismic distances are different. However, the uncertainties are such that this may not be significant. Although the seismic distances for the cluster members are self consistent they are somewhat larger than the Hipparcos distance. This is an issue that should be considered elsewhere. Models including thermohaline instability and rotation-induced mixing, together with the seismically determined masses can explain the chemical properties of red giant targets. However, with this sample of stars we cannot perform stringent tests of the current stellar models. Tighter constraints on the physics of the models would require the measurement of the core and surface rotation rates, and of the period spacing of gravity-dominated mixed modes. A larger number of stars with longer times series, as provided by Kepler or expected with Plato, would help ensemble asteroseismology.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Lagarde, N.; School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
Miglio, A.; School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK ; Stellar Astrophysics Centre (SAC), Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000, Aarhus C, Denmark
Eggenberger, P.; Geneva Observatory, University of Geneva, Chemin des Maillettes 51, 1290, Versoix, Switzerland
Morel, Thierry ; Université de Liège > Groupe d'astrophysique des hautes énergies (GAPHE)
Montalbán, J.; Departement of Physics and Astronomy G. Galilei, University of Padova, Vicolo dell'Osservatorio 3, 35122, Padova, Italy
Mosser, B.; LESIA, Observatoire de Paris, PSL Research University, CNRS, Université Pierre et Marie Curie, Université Denis Diderot, 92195, Meudon Cedex, France
Rodrigues, T. S.; Departement of Physics and Astronomy G. Galilei, University of Padova, Vicolo dell'Osservatorio 3, 35122, Padova, Italy ; Osservatorio Astronomico di Padova INAF, Vicolo dell'Osservatorio 5, 35122, Padova, Italy ; Laboratório Interinstitucional de e-Astronomia, LIneA, Rua Gal. Jose Cristino 77, 20921-400, Rio de Janeiro, RJ, Brazil
Girardi, L.; Osservatorio Astronomico di Padova INAF, Vicolo dell'Osservatorio 5, 35122, Padova, Italy ; Laboratório Interinstitucional de e-Astronomia, LIneA, Rua Gal. Jose Cristino 77, 20921-400, Rio de Janeiro, RJ, Brazil
Rainer, M.; INAF-Osservatorio Astronomico di Brera, via E. Bianchi 46, 23807, Merate, LC, Italy
Poretti, E.; INAF-Osservatorio Astronomico di Brera, via E. Bianchi 46, 23807, Merate, LC, Italy
Barban, C.; LESIA, Observatoire de Paris, PSL Research University, CNRS, Université Pierre et Marie Curie, Université Denis Diderot, 92195, Meudon Cedex, France
Hekker, S.; Stellar Astrophysics Centre (SAC), Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000, Aarhus C, Denmark ; Astronomical Institute "Anton Pannekoek", University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands ; Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, 37077, Göttingen, Germany
Kallinger, T.; Institute for Astrophysics, University of Vienna, Türkenschanzstrasse 17, 1180, Vienna, Austria
Valentini, Marica ; Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16, 14482, Potsdam, Germany
Carrier, F.; Katholieke Universiteit Leuven, Departement Natuurkunde en Sterrenkunde, Instituut voor Sterrenkunde, Celestijnenlaan 200D, 3001, Leuven, Belgium
Hareter, M.; Institute for Astrophysics, University of Vienna, Türkenschanzstrasse 17, 1180, Vienna, Austria
Mantegazza, L.; INAF-Osservatorio Astronomico di Brera, via E. Bianchi 46, 23807, Merate, LC, Italy
Elsworth, Y.; School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK ; Stellar Astrophysics Centre (SAC), Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000, Aarhus C, Denmark
Michel, E.; LESIA, Observatoire de Paris, PSL Research University, CNRS, Université Pierre et Marie Curie, Université Denis Diderot, 92195, Meudon Cedex, France
Baglin, A.; LESIA, Observatoire de Paris, PSL Research University, CNRS, Université Pierre et Marie Curie, Université Denis Diderot, 92195, Meudon Cedex, France)