A Transiting Extrasolar Giant Planet around the Star OGLE‐TR‐10

We report a transiting extrasolar giant planet around the star OGLE-TR-10(orbital period = 3.1 days), which was uncovered as a candidate by the OGLEteam in their photometric survey towards the Galactic center (Udalski et al,2002a). We observed OGLE-TR-10 spectroscopically over a period of two years(2002-2004) using the HIRES instrument with an iodine cell on the Keck Itelescope, and measured small radial velocity variations that are consistentwith the presence of a planetary companion. This confirms the earlieridentification of OGLE-TR-10b by our team and also recently by Bouchy et al(2004a) as a possible planet. Additionally, in this paper we are able to ruleout a blend scenario as an alternative explanation. From an analysis combiningall available radial velocity measurements with the OGLE light curve we findthat OGLE-TR-10b has a mass of 0.57+/-0.12 MJup and a radius of 1.24+/-0.09RJup. These parameters bear close resemblance to those of the first knowntransiting extrasolar planet, HD 209458b.Comment: accepted to Astrophysical Journa