Stellar Activity Manifesting at a One-year Alias Explains Barnard b as a False Positive

  title={Stellar Activity Manifesting at a One-year Alias Explains Barnard b as a False Positive},
  author={Jack Lubin and Paul Robertson and Gudmundur Stef{\'a}nsson and Joe P. Ninan and Suvrath Mahadevan and Michael Endl and Eric B. Ford and Jason T. Wright and Corey Beard and Chad F. Bender and William D. Cochran and Scott A. Diddams and Connor Fredrick and Samuel Halverson and Shubham Kanodia and Andrew J. Metcalf and Lawrence W. Ramsey and Arpita Roy and Christian Schwab and Ryan C. Terrien},
  journal={The Astronomical Journal},
Barnard’s star is among the most studied stars given its proximity to the Sun. It is often considered the radial velocity (RV) standard for fully convective stars due to its RV stability and equatorial decl. Recently, an Msini=3.3M⊕ super-Earth planet candidate with a 233 day orbital period was announced by Ribas et al. New observations from the near-infrared Habitable-zone Planet Finder (HPF) Doppler spectrometer do not show this planetary signal. We ran a suite of experiments on both the… 
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