An Observing Campaign at Calar Alto to Search for Short Period Planets around Evolved Stars
Final Report Abstract
The funded observing campaign of June 2014 at Calar Alto Observatory was very successful. Most of the nights the weather was good, and 9 high-resolution spectra were obtained for each of two giant stars with transiting planet candidates. Radial velocities were derived and - together with spectra taken at the NOT - we could indeed confirm the planetary nature of both objects. The object Kepler 91 b is a hot Jupiter-like planet with a period of ~6 days. It has a mass of 0.86 MJ with a semi-major axis of 0.07 AU. This planet is the first one found to transit a giant star so far. Considering that an orbital solution for this object was recently published (August 2014), we will evaluate the value of another publication with a more precise orbit. The object KOI-1299 b is the second (after Kepler 91 b) giant planet known to transit a giant star. With a semi-major axis of 0.3 AU it is the first warm Jupiter (T eff = 940 K) discovered orbiting a giant star. In addition, it is a very eccentric planet (e=0.48) and, with a density of 5.9 g/cm3 , KOI-1299 b is among the most dense planets found so far.
