EDP Sciences
Free access
Volume 496, Number 2, March III 2009
Page(s) L5 - L8
Section Letters
DOI http://dx.doi.org/10.1051/0004-6361/200911689
Published online 18 February 2009
A&A 496, L5-L8 (2009)
DOI: 10.1051/0004-6361/200911689


HD 60532, a planetary system in a 3:1 mean motion resonance

J. Laskar1 and A. C. M. Correia1, 2

1  ASD, IMCCE, CNRS-UMR8028, Observatoire de Paris, UPMC, 77 avenue Denfert-Rochereau, 75014 Paris, France
    e-mail: laskar@imcce.fr
2  Departamento de Física, Universidade de Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
    e-mail: correia@ua.pt

Received 20 January 2009 / Accepted 3 February 2009

A recent paper has reported that there is a planetary system around the star HD 60532, composed of two giant planets in a possible 3:1 mean motion resonance, which should be confirmed within the next decade. Here we show that the analysis of the global dynamics of the system already allows this resonance to be confirmed. The present best fit to the data corresponds to this resonant configuration, and the system is stable for at least 5 Gyr. The 3:1 resonance is so robust that stability is still possible for a wide variety of orbital parameters around the best-fit solution and would also be if the inclination of the system orbital plane is as small as 15° with respect to the plane of the sky. Moreover, if the inclination is taken as a free parameter in the adjustment to observations, we find an inclination ~20°, which corresponds to Mb = 3.1 $M_{\rm Jup}$ and Mc = 7.4 $M_{\rm Jup}$ for the planetary companions.

Key words: stars: individual: HD 60532 -- stars: planetary systems -- techniques: radial velocities -- methods: numerical

© ESO 2009