High‐Resolution Spectroscopic Follow‐up of OGLE Planetary Transit Candidates in the Galactic Bulge: Two Possible Jupiter‐Mass Planets and Two Blends

We report the results of our campaign to follow-up spectroscopically severalcandidate extrasolar transiting planets from the OGLE-III survey in thedirection of the Galactic center, announced in 2001 (Udalski et al 2002a,b).All of these objects present shallow and periodic dips in brightness that maybe due to planetary companions. Our high-resolution Keck I/HIRES observationshave revealed two interesting cases (OGLE-TR-10 with a period of 3.1 days, andOGLE-TR-58 with a period of 4.3 days) that show no radial velocity variationsat the level of 100--200 m/s. If orbited by companions, their masses would besimilar to Jupiter. With the information in hand (including the light curves)we are not able to rule out that these candidates are instead the result ofcontamination from an eclipsing binary in the same line of sight (a "blend").We discuss also the case of OGLE-TR-56 that was recently reported by Konacki etal (2003) to have a Jupiter-size companion, based on an earlier analysis of ourdata, and we present supporting information. Two other candidates, OGLE-TR-3and OGLE-TR-33, show clear evidence that they are blends.Comment: Submitted to Ap