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تسجيل مستخدم جديدSeismic investigation of the {gamma} Dor star KIC 6462033: The first results of Kepler and ground-based follow up observations
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We present the first preliminary results on the analysis of ground-based time series of the {gamma} Dor star KIC 6462033 (TYC 3144-646-1, V = 10.83, P = 0.69686 d) as well as Kepler photometry in order to study pulsational behaviour in this star.{gamma} Dor variables, which exhibit g-mode pulsations, are promising asteroseismic targets to understand their rich complexity of pulsational characteristics in detail. In order to achieve this goal, intensive and numerous multicolour and high resolution spectroscopic observations are also required, to complete space-based data aimed at the determination of their physical parameters.
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The Kepler space mission, successfully launched in March 2009, is providing continuous, high-precision photometry of thousands of stars simultaneously. The uninterrupted time-series of stars of all known pulsation types are a precious source for aste
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We present results of an asteroseismic study on the $gamma$ Dor type {it Kepler} target KIC,6462033. {it Kepler} photometry is used to derive the frequency content and principal modes. High-dispersion ground-based spectroscopy is also carried out in
order to determine the atmospheric parameters and projected rotational velocity. From an analysis of the {it Kepler} long cadence time series, we find that the light curve of KIC,6462033 is dominated by three modes with frequencies $f_{1}$=0.92527, $f_{2}$=2.03656 and $f_{3}$=1.42972 d$^{-1}$ as well as we detect more than a few hundreds of combination terms. However, two other independent frequencies appear to have lower amplitudes in addition to these three dominant terms. No significant peaks are detected in the region $>$ 5 d$^{-1}$. We therefore confirm that KIC,6462033 pulsates in the frequency range of $gamma$ Dor type variables, and a future study will allow us to investigate modal behaviour in this star.
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