The HARPS search for southern extra-solar planets – XLV. Two Neptune mass planets orbiting HD 13808: a study of stellar activity modelling’s impact on planet detection

  title={The HARPS search for southern extra-solar planets – XLV. Two Neptune mass planets orbiting HD 13808: a study of stellar activity modelling’s impact on planet detection},
  author={Eva-Maria Ahrer and D. Queloz and Vinesh M. Rajpaul and Damien S{\'e}gransan and F. Bouchy and R Hall and W. J. Handley and Cristophe Lovis and Michel Mayor and A. Mortier and Francesco Pepe and Susan E. Thompson and St{\'e}phane Udry and N Unger},
  journal={Monthly Notices of the Royal Astronomical Society},
  • E. AhrerD. Queloz N. Unger
  • Published 30 March 2005
  • Physics, Geology
  • Monthly Notices of the Royal Astronomical Society
We present a comprehensive analysis of 10 yr of HARPS radial velocities (RVs) of the K2V dwarf star HD 13808, which has previously been reported to host two unconfirmed planet candidates. We use the state-of-the-art nested sampling algorithm PolyChord to compare a wide variety of stellar activity models, including simple models exploiting linear correlations between RVs and stellar activity indicators, harmonic models for the activity signals, and a more sophisticated Gaussian process… 

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