Detecting Extra-solar Planets with a Bayesian hybrid MCMC Kepler periodogram

P. C. Gregory

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arXiv · 0902.2014

Detecting Extra-solar Planets with a Bayesian hybrid MCMC Kepler periodogram

P. C. Gregory

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Abstract

A Bayesian re-analysis of published radial velocity data sets is providing evidence for additional planetary candidates. The nonlinear model fitting is accomplished with a new hybrid Markov chain Monte Carlo (HMCMC) algorithm which incorporates parallel tempering, simulated annealing and genetic crossover operations. Each of these features facilitate the detection of a global minimum in chi^2. By combining all three, the HMCMC greatly increases the probability of realizing this goal. When applied to the Kepler problem it acts as a powerful multi-planet Kepler periodogram for both parameter estimation and model selection. The HMCMC algorithm is embedded in a unique two stage adaptive control system that automates the tuning of the MCMC proposal distributions through an annealing operation.

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P. C. Gregory. 2009-02-12. Detecting Extra-solar Planets with a Bayesian hybrid MCMC Kepler periodogram. https://arxiv.org/abs/0902.2014

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