(Proposal ID) S14A-096

(PI) Sato Bunei

(Proposal Title)
 Confirmation of Kepler Planet Candidates around Giants

(Abstract)
Detecting planetary transits is extremely valuable not only because it makes 
an independent confirmation of a planet from Doppler method but also because 
the photometric transits yield unambiguous information on planet masses and 
radii, and thus mean density and interior structure, and obliquity of 
planetary orbits. Planets around giants and subgiants have been intensively 
surveyed over the decade by precise radial velocity (RV) measurements, mainly 
from the viewpoint of planet searches around intermediate-mass (1.5-5M_sun) 
stars. The planets show remarkable properties in their masses and orbital 
parameters. Unfortunately, however, it is quite difficult to detect transiting 
ones around such evolved stars because of the large sizes of the host stars. 
Therefore, our understanding of properties of planets around intermediate-mass 
stars are still far behind from those around solar-like stars. In S13B, we 
made the first RV follow-up observations with HDS for the transiting planet 
candidates around giants found by Kepler space telescope, and identified 
promising candidates of true transiting planets. Here we propose to take 
additional RV data for them with HDS in order to make sure that the RV 
periodicity is the same as the transit one.