EXOFIT: Bayesian Estimation of Orbital Parameters of Extrasolar Planets

TL;DR

EXOFIT is a Bayesian tool utilizing Markov Chain Monte Carlo methods to estimate orbital parameters of extrasolar planets from radial velocity data, providing a new approach for analyzing planetary systems.

Contribution

It introduces EXOFIT, a novel Bayesian estimation tool that can analyze one or two planets simultaneously using MCMC, improving orbital parameter estimation accuracy.

Findings

EXOFIT's orbital period estimates align with published data.

It tends to prefer lower eccentricity solutions for high-eccentricity planets.

Validated on 30 stars, showing consistent results with existing methods.

Abstract

We introduce EXOFIT, a Bayesian tool for estimating orbital parameters of extrasolar planets from radial velocity measurements. EXOFIT can search for either one or two planets at present. EXOFIT employs Markov Chain Monte Carlo method implemented in an object oriented manner. As an example we re-analyze the orbital solution of HD155358 and the results are compared with that of the published orbital parameters. In order to check the agreement of the EXOFIT orbital parameters with the published ones we examined radial velocity data of 30 stars taken randomly from www.exoplanet.eu. We show that while orbital periods agree in both methods, EXOFIT prefers lower eccentricity solutions for planets with higher (e >=0.5) orbital eccentricities.