2010A&A...509A..24H

Our primary goal is to search for planets around intermediate mass stars. We are also interested in studying the nature of radial velocity (RV) variations of K giant stars. We selected about 55 early K giant (K0-K4) stars brighter than fifth magnitude that were observed using BOES, a high resolution spectrograph attached to the 1.8m telescope at BOAO (Bohyunsan Optical Astronomy Observatory). BOES is equipped with I₂ absorption cell for high precision RV measurements. We detected a periodic radial velocity variations in the K0 III star γ¹Leonis with a period of P=429days. An orbital fit of the observed RVs yields a period of P=429days, a semi-amplitude of K=208/ms, and an eccentricity of e=0.14. To investigate the nature of the RV variations, we analyzed the photometric, CaII λ 8662 equivalent width, and line-bisector variations of γ¹ Leonis . We conclude that the detected RV variations can be best explained by a planetary companion with an estimated mass of msini=8.78M_Jupiter and a semi-major axis of a=1.19AU, assuming a stellar mass of 1.23M_☉.