Poster Abstracts

Name/Affiliation:  Adriana Valio (Mackenzie University, Brazil)

Title:  Determining stellar properties from planetary transits

During the eclipse of a star by its orbiting planet, spots and other features on the surface of the host star may be occulted. This will cause small variations in the star light curve. Detailed analysis of these variations during planetary transits provides a wealth of information about starspot properties such as size, position, temperature (i.e. intensity), and magnetic fields. When multiple transits are detectable, it may be possible to detect the same spot on different transits and thus determine the stellar rotation. Assuming a rotation profile of the star with latitude, for example solar-like, it may also be possible to estimate stellar differential rotation. By simulating the passage of a planet (dark disk) in front of a star with multiple spots of different sizes, intensities, and positions on its surface, the stellar properties are determined. The light curves of known planets detected by the CoRoT and Kepler satellite are analyzed and the estimates of the starspots physical characteristics and the host star rotation and differential rotation presented.