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arXiv · 1611.07648

The Pan-Pacific Planet Search VI: Giant planets orbiting HD 86950 and HD 222076

Robert A. Wittenmyer·M. I. Jones·Jinglin Zhao·J. P. Marshall·R. P. Butler·C. G. Tinney·Liang Wang·John Asher Johnson
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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$\pm$57 days at $a=2.72\pm$0.08 AU, and m sin $i=3.6\pm$0.7 Mjup. HD 222076b has $P=871\pm$19 days at $a=1.83\pm$0.03 AU, and m sin $i=1.56\pm$0.11 Mjup. These two giant planets are typical of the population of planets known to orbit evolved stars. In addition, we find a high-amplitude periodic velocity signal ($K\sim$50 m/s) 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.

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Robert A. Wittenmyer, M. I. Jones, Jinglin Zhao, J. P. Marshall, R. P. Butler, C. G. Tinney, Liang Wang, John Asher Johnson. 2016-11-23. The Pan-Pacific Planet Search VI: Giant planets orbiting HD 86950 and HD 222076. https://doi.org/10.3847/1538-3881%2F153%2F2%2F51

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