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arXiv · 1510.04343

The Pan-Pacific Planet Search III: Five companions orbiting giant stars

R. A. Wittenmyer·R. P. Butler·L. Wang·C. Bergmann·G. S. Salter·C. G. Tinney·John Asher Johnson
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Abstract

We report a new giant planet orbiting the K giant HD 155233, as well as four stellar-mass companions from the Pan-Pacific Planet Search, a southern hemisphere radial velocity survey for planets orbiting nearby giants and subgiants. We also present updated velocities and a refined orbit for HD 47205b (7 CMa b), the first planet discovered by this survey. HD 155233b has a period of 885$\pm$63 days, eccentricity e=0.03$\pm$0.20, and m sin i=2.0$\pm$0.5 M_jup. The stellar-mass companions range in m sin i from 0.066 M_sun to 0.33 M_sun. Whilst HD 104358B falls slightly below the traditional 0.08 M_sun hydrogen-burning mass limit, and is hence a brown dwarf candidate, we estimate only a 50% a priori probability of a truly substellar mass.

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R. A. Wittenmyer, R. P. Butler, L. Wang, C. Bergmann, G. S. Salter, C. G. Tinney, John Asher Johnson. 2015-10-14. The Pan-Pacific Planet Search III: Five companions orbiting giant stars. https://doi.org/10.1093/mnras%2Fstv2396

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