Starspot temporal evolution

• Grant number: 12/17062-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2012
• End date: July 31, 2013
• Field of knowledge: Physical Sciences and Mathematics - Astronomy - Stellar Astrophysics
• Principal Investigator: Adriana Benetti Marques Valio
• Grantee: Dirceu Yuri Simplicio Netto
• Host Institution: Escola de Engenharia (EE). Universidade Presbiteriana Mackenzie (UPM). São Paulo , SP, Brazil

Abstract

Currently, it is believed that about 10% of Sun-like stars harbour planets around them. Today there are nearly 800 known planets and approximately 30% of these eclipses their host star. When passing in front of the star, the planet might cross in front of a spot on the surface of the star causing a small variation in the light curve during the transit. By using a model that simulates the transit of a planet in front of a star with spots, it is possible to characterize these spots. The fit of these small signatures in the light curve caused by the presence of spots provides the spot physical parameters such as size and intensity. This method has been applied to five stars observed by COROT. The objective of this work is to use these results to study the temporal evolution of these spots, that is, as the spots on the surface of other stars grow or shrink and how its brightness changes as it evolves. The project also aims to estimate the average lifetime of the spots and to study whether the spot lifetime varies from star to star depending on its type.