A Search for Exoplanets around Northern Circumpolar Stars. VI. Detection of Planetary Companions Orbiting the Giants HD 60292 and HD 112640
We report the detection of exoplanet candidates in orbits around HD 60292 and HD 112640 from a radial velocity (RV) survey. The stars exhibit RV variations with periods of 495+/-3 days and 613+/-6 days, respectively. These detections are part of the Search for Exoplanets around Northern Circumpolar Stars (SENS) survey using the fiber-fed Bohyunsan Observatory Echelle Spectrograph installed at the 1.8-m telescope of the Bohyunsan Optical Astronomy Observatory in Korea. The aim of the survey is to search for planetary or substellar companions. We argue that the periodic RV variations are not related to surface inhomogeneities; rather, Keplerian motions of planetary companions are the most likely interpretation. Assuming stellar masses of 1.7+/-0.2 M_sun (HD 60292) and 1.8+/-0.2 M_sun (HD 112640), we obtain minimum planetary companion masses of 6.5+/-1.0 M_Jupiter and 5.0+/-1.0 M_Jupiter, and periods of 495.4+/-3.0 days and 613.2+/-5.8 days, respectively.