A Sub-Saturn Mass Planet Orbiting HD 3651

  title={A Sub-Saturn Mass Planet Orbiting HD 3651},
  author={Debra A. Fischer and R. Paul Butler and Geoffrey W. Marcy and Steven S. Vogt and Gregory W. Henry},
  journal={The Astrophysical Journal},
  pages={1081 - 1087}
We report precise Doppler velocities of HD 3651 obtained at Lick and Keck Observatories. The velocities reveal evidence of a planetary companion with an orbital period of 62.23 ± 0.03 days, an eccentricity of 0.63 ± 0.04, and a velocity semiamplitude of 15.9 ± 1.7 m s-1. With an assumed mass of 0.79 M☉ for this K0 V star, we derive M sin i = 0.20MJ and a semimajor axis of 0.284 AU. The star is chromospherically inactive, with log R = -5.01, and 10 years of observations at Fairborn Observatory… 

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