Centrum Astronomii
Uniwersytet Mikołaja Kopernika

Asymmetric light curve and Transit Duration Variations in KOI-13

Gyula Szabo

Asymmetric light curve and Transit Duration Variations in KOI-13

The A-type star KOI-13 hosts a hot Jupiter with 1.76 day period. The transit light curve is asymmetric due to the non-isotropic surface brightness of the host star, due to its rotation and gravity darkening. This allowed us to infer to the stellar obliquity of KOI-13. There is an additional periodicity of 25.4 hour which we interpret as the stellar rotation. This period is in an exact 3:5 resonance with the orbital period, putting KOI-13 into the few known systems with resonance between the stellar spin and the orbital period. We found that the transit duration of KOI-13 is gradually increasing, very probably due to a gradual increasing of the impact parameter. The rate of this variation is consistent with perturbations by the rapidly rotating host star, and suggests that KOI-13 will no more be a transiting system in 75-100 years.

Data
11.06.2012 - 11:15
Miejsce
Sala KRa