Signals embedded in the radial velocity noise - Periodic variations in the τ Ceti velocities

  title={Signals embedded in the radial velocity noise - Periodic variations in the $\tau$ Ceti velocities},
  author={Mikko Tuomi and Hugh R. A. Jones and James S. Jenkins and Christopher G. Tinney and R. Paul Butler and Steven S. Vogt and John R. Barnes and Robert A. Wittenmyer and S. O’Toole and Jonathan Horner and Jeremy Bailey and B. D. Carter and Duncan J. Wright and Graeme S. Salter and David J. Pinfield},
  journal={Astronomy and Astrophysics},
Context. The abilities of radial velocity exoplanet surveys to detect the lowest-mass extra-solar planets are currently limited by a combination of instrument precision, lack of data, and 'jitter'. Jitter is a general term for any unknown features in the noise, and reflects a lack of detailed knowledge of stellar physics (asteroseismology, starspots, magnetic cycles, granulation, and other stellar surface phenomena), as well as the possible underestimation of instrument noise. Aims. We study… 
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