THE PAN-PACIFIC PLANET SEARCH. VI. GIANT PLANETS ORBITING HD 86950 AND HD 222076
No Thumbnail Available
Date
2017
Journal Title
Journal ISSN
Volume Title
Publisher
IOP PUBLISHING LTD
Abstract
We report the detection of two new planets orbiting the K giants HD 86950 and HD 222076, based on precise radial velocities obtained with three instruments: AAT/UCLES, FEROS, and CHIRON. HD 86950b has a period of 1270 +/- 57 days at a=2.72 +/- 0.08 AU, and m sin i=3.6 +/- 0.7 M-Jup. HD 222076b has P=871 +/- 19 days at a=1.83 +/- 0.03 AU, and m sin i=1.56 +/- 0.11 M-Jup. These two giant planets are typical of the population of planets known to orbit evolved stars. In addition, we find a high-amplitude periodic velocity signal (K similar to 50 m/s(-1)) in HD 29399, and show that it is due to stellar variability rather than Keplerian reflex motion. We also investigate the relation between planet occurrence and host-star metallicity for the 164-star Pan-Pacific Planet Search sample of evolved stars. In spite of the small sample of PPPS detections, we confirm the trend of increasing planet occurrence as a function of metallicity found by other studies of planets orbiting evolved stars.
Description
Keywords
planetary systems, stars: individual(HD 29399, HD 86950, HD 222076), techniques: radial velocities, PRECISE RADIAL-VELOCITIES, SPECTROSCOPIC STELLAR PARAMETERS, ALL-SKY SURVEY, EVOLVED STARS, HOST STAR, FUNDAMENTAL PARAMETERS, HABITABLE-ZONE, MASS STARS, METALLICITY, COMPANIONS