Poster Abstracts

Name/Affiliation:  Meunier Nadege (Institut d’Astrophysique et de Planétologie de Grenoble, Université Joseph Fourier)

Title:  Simulation of granulation and supergranulation radial velocity and photometric time series

Stellar variability at all time-scales strongly impacts the ability to detect exoplanets, in particular when using radial velocity (RV). Solar RV variability at time-scales of months to decades have been studied (e.g. Lagrange et al. 2010, Meunier et al 2010.), taking into account magnetic activity (spot, plages, inhibition of convection in plages). Such activity can impact the interpretation of RV data of solar-like stars. In the case of stars, part of the small-scale variability also represents an important factor (Aigrain et al. 2004 for photometry). Part of the small-scale variability can be averaged out by dedicated observational strategy (Dumusque et al. 2011). We have simulated a collection of granules or supergranules evolving in time in order to reproduce realistic solar photometric and RV time series, and studied the impact on RV observations aiming at detecting exoplanets. Long-term variability is also explored.