Advances in Astronomy and Space Physics, Volume 1 (2011)

Modeling radial velocities of HD 240210 with the Genetic Algorithms

A. Rozenkiewicz, K. Gozdziewski, C. Migaszewski

Toruń Centre for Astronomy, Nicolaus Copernicus University, Gagarin Str. 11, 87-100 Toruń, Poland

More than 450 extrasolar planets are known to date. To detect these intriguing objects many photometric and radial velocity surveys are in progress. We developed the Keplerian FITting code, to model published and available radial velocity data. This code is based on a hybrid, quasi-global optimization technique relying on the Genetic Algorithms and simplex algorithm. Here, we re-analyse the radial velocity data of evolved K3III star HD 240210. We found three equally good solutions which might be interpreted as signals of two-planet systems. Remarkably, one of these best-fits describes long-term stable two-planet system, involved in the 2:1 mean motion resonance. It may be the first instance of this strong mean motion resonance in a multi-planet system hosted by evolved star, as the 2:1 mean motion resonance configurations are already found around a few sun-like dwarfs.