Ghost in the time series: no planet for Alpha Cen B

  title={Ghost in the time series: no planet for Alpha Cen B},
  author={Vinesh M. Rajpaul and Suzanne Aigrain and Stephen J. Roberts},
  journal={Monthly Notices of the Royal Astronomical Society},
We re-analyse the publicly available radial velocity (RV) measurements for Alpha Cen B, a star hosting an Earth-mass planet candidate, Alpha Cen Bb, with 3.24 day orbital period. We demonstrate that the 3.24 d signal observed in the Alpha Cen B data almost certainly arises from the window function (time sampling) of the original data. We show that when stellar activity signals are removed from the RV variations, other significant peaks in the power spectrum of the window function are… 

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