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

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 نشر من قبل Robert Wittenmyer
 تاريخ النشر 2015
  مجال البحث فيزياء
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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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