An improved determination of convective granulation noise properties using 3D stellar atmosphere models
Luisa Fernanda Rodriguez Diaz (SAC, Aarhus Universtity)
The study of stellar granulation has vastly improved thanks to the observations made by Kepler, which have shown that the stellar flux produces stochastic brightness fluctuations. These fluctuations need to be quantified in order to detect and characterize exoplanets. In this work, we aim to provide new scaling relations between granulation properties, such as the rms brightness fluctuation and characteristic timescale, with stellar parameters such as the peak frequency, using long time series of 3D stellar atmosphere models at different metallicities and across the HR diagram, generated with the STAGGER-code. To validate our results, we compared our theoretical granulation properties with the values of a large sample of Kepler stars from the literature, and analyzed selected stars with accurate stellar parameters as well. In this talk I will present the relations that our 3D models have with stellar parameters and the agreement with observational data.