Doppler follow-up of OGLE transiting companions in the Galactic bulge

Two years ago, the OGLE-III survey (Optical Gravitational Lensing Experiment) announced the detection of54short period multi-transiting objects in the Galactic bulge (Udalski etal. [CITE],b). Some of these objects were considered to be potential hot Jupiters. In order to determine the true nature of these objects and to characterize their actual mass, we conducted a radial velocity follow-up of 18 of the smallest transiting candidates. We describe here our procedure and report the characterization of 8low-mass star-transiting companions, 2grazing eclipsing binaries, 2triple systems, 1confirmed exoplanet (OGLE-TR-56b), 1possible exoplanet (OGLE-TR-10b), 1clear false positive and 3unsolved cases. The variety of cases encountered in our follow-up covers a large part of the possible scenarios occurring in the search for planetary transits. As a by-product our program yields precise masses and radii of low mass stars.

Based on observations collected with the UVES and FLAMES spectrographs at the VLT/UT2 Kueyen telescope (Paranal Observatory, ESO, Chile: program 70.C-0209 and 71.C-0251).