Description
We present an update to seven stars with long-period planets or planetary candidates using new and archival radial velocities from Keck-HIRES and literature velocities from other telescopes. Our updated analysis better constrains orbital parameters for these planets, four of which are known multi-planet systems. HD24040b and HD183263c are super-Jupiters with circular orbits and periods longer than 8yr. We present a previously unseen linear trend in the residuals of HD 66428 indicative of an additional planetary companion. We confirm that GJ 849 is a multi-planet system and find a good orbital solution for the c component: it is a 1M_Jup_ planet in a 15yr orbit (the longest known for a planet orbiting an M dwarf). We update the HD74156 double-planet system. We also announce the detection of HD145934b, a 2M_Jup_ planet in a 7.5yr orbit around a giant star. Two of our stars, HD187123 and HD217107, at present host the only known examples of systems comprising a hot Jupiter and a planet with a well constrained period greater than 5yr, and with no evidence of giant planets in between. Our enlargement and improvement of long-period planet parameters will aid future analysis of origins, diversity, and evolution of planetary systems.
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