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HD 52265 is the only known exoplanet-host star selected as a main target for the seismology programme of the CoRoT satellite. As such, it will be observed continuously during five months, which is of particular interest in the framework of planetary systems studies. This star was misclassified as a giant in the Bright Star Catalog, while it is more probably on the main-sequence or at the beginning of the subgiant branch. We performed an extensive analysis of this star, showing how asteroseismology may lead to a precise determination of its external parameters and internal structure. We first reviewed the observational constraints on the metallicity, the gravity and the effective temperature derived from the spectroscopic observations of HD 52265. We also derived its luminosity using the Hipparcos parallax. We computed the evolutionary tracks for models of various metallicities which cross the relevant observational error boxes in the gravity-effective temperature plane. We selected eight different stellar models which satisfy the observational constraints, computed their p-modes frequencies and analysed specific seismic tests. The possible models for HD 52265, which satisfy the constraints derived from the spectroscopic observations, are different in both their external and internal parameters. They lie either on the main sequence or at the beginning of the subgiant branch. The differences in the models lead to quite different properties of their oscillation frequencies. We give evidences of an interesting specific behaviour of these frequencies in case of helium-rich cores: the ``small separations may become negative and give constraints on the size of the core. We expect that the observations of this star by the CoRoT satellite wi ll allow choosing between these possible models.
This paper presents a detailed and precise study of the characteristics of the Exoplanet Host Star and CoRoT main target HD 52265, as derived from asteroseismic studies. The results are compared with previous estimates, with a comprehensive summary a
The star HD 52265 is a G0V metal-rich exoplanet-host star observed in the seismology field of the CoRoT space telescope from November 2008 to March 2009. The satellite collected 117 days of high-precision photometric data on this star, showing that i
The CoRoT mission is in its third year of observation and the data from the second long run in the galactic centre direction are being analysed. The solar-like oscillating stars that have been observed up to now have given some interesting results, s
The satellite CoRoT (Convection, Rotation, and planetary Transits) has provided high-quality data for almost six years. We show here the asteroseismic analysis and modeling of HD169392A, which belongs to a binary system weakly gravitationally bound a
Solar-like oscillations are stochastically excited by turbulent convection at the surface layers of the stars. We study the role of the surface metal abundance on the efficiency of the stochastic driving in the case of the CoRoT target HD 49933. We c