Transiting exoplanets from the CoRoT space mission IX. CoRoT-6b: a transiting hot Jupiter planet in an 8.9d orbit around a low-metallicity star

The CoRoT satellite exoplanetary team announces its sixth transiting planet in this paper. We describe and discuss the satellite observations as well as the complementary ground-based observations - photometric and spectroscopic - carried out to assess the planetary nature of the object and determine its specific physical parameters. The discovery reported here is a hot Jupiter planet in an 8.9d orbit, 18 stellar radii, or 0.08 AU, away from its primary star, which is a solar-type star (F9V) with an estimated age of 3.0 Gyr. The planet mass is close to 3 times that of Jupiter. The star has a metallicity of 0.2 dex lower than the Sun, and a relatively high Li-7 abundance. While the light curve indicates a much higher level of activity than, e. g., the Sun, there is no sign of activity spectroscopically in e. g., the [Ca II] H&K lines.