Talk abstract details

Studying Stellar magnetic activity with asteroseismic measurements.
R.A. Garcia, S. Mathur, J. Ballot, C. Regulo, D. Salabert, T. Ceillier and T. Metcalfe, A. Morgenthaler and P. Petit


Long and continuous photometric coverage of stars provide a great opportunity to study their stellar variability and, in particular, stellar activity cycles. A surface stellar activity proxy can be built from the variance of the light curve as the spots crossing the visible disk of stars produce a modulation in the light curve. The higher the number of spots is, the larger the variance is. Moreover, if we have access to acoustic modes, we can study the perturbations induced below the surface by the magnetic cycle in the properties of the modes, such as their amplitudes and frequencies. Although solar-like stars can have magnetic activity cycles longer than the length of current asteroseismic observations performed with CoRoT and Kepler, several authors have suggested a relation between the length of the cycles and the rotation period. Therefore, for rapidly rotating (young) stars, the cycles can be of a few years and therefore accessible to our current measurements. In this talk we propose to review some of the open questions we have and how CoRoT and Kepler measurements, with the support of ground based observations, are shedding new light onto this field.

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