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arXiv · 1601.07495

Uncovering the planets and stellar activity of CoRoT-7 using only radial velocities

J. P. Faria·R. D. Haywood·B. J. Brewer·P. Figueira·M. Oshagh·A. Santerne·N. C. Santos
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Abstract

Stellar activity can induce signals in the radial velocities of stars, complicating the detection of orbiting low-mass planets. We present a method to determine the number of planetary signals present in radial-velocity datasets of active stars, using only radial-velocity observations. Instead of considering separate fits with different number of planets, we use a birth-death Markov chain Monte Carlo algorithm to infer the posterior distribution for the number of planets in a single run. In a natural way, the marginal distributions for the orbital parameters of all planets are also inferred. This method is applied to HARPS data of CoRoT-7. We confidently recover both CoRoT-7b and CoRoT-7c although the data show evidence for additional signals.

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J. P. Faria, R. D. Haywood, B. J. Brewer, P. Figueira, M. Oshagh, A. Santerne, N. C. Santos. 2016-02-03. Uncovering the planets and stellar activity of CoRoT-7 using only radial velocities. https://doi.org/10.1051/0004-6361%2F201527899

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