A Possible New Transiting Planet

Astrophysics, abstract
astro-ph/0303183

From: Stefan Dreizler <dreizler@astro.uni-tuebingen.de>

Date: Sat, 8 Mar 2003 17:51:39 GMT   (126kb)

Authors:
S. Dreizler,
P. Hauschildt,
W. Kley,
T. Rauch,
S.L. Schuh,
K. Werner,
B. Wolff

Comments: 9 pages, 12 figures, A&A in press

Recently, 59 low-luminosity object transits were reported from the Optical
Gravitational Lensing Experiment (OGLE). Our follow-up low-resolution
spectroscopy of 16 candidates provided two objects, OGLE-TR-3 and OGLE-TR-10,
which have companions with radii compatible with those of gas-giant planets.
Further high-resolution spectroscopy revealed a very low velocity variation
(<500m/s) of the host star OGLE-TR-3 which may be caused by its unseen
companion. An analysis of the radial velocity and light curve results in M<2.5
M_jup, R<1.6 R_jup, and an orbital separation of about 5 R_sol, which makes it
the planet with the shortest period known. This allows to identify the
low-luminosity companion of OGLE-TR-3 as a possible new gas-giant planet. If
confirmed, this makes OGLE-TR-3 together with OGLE-TR-56 the first extrasolar
planets detected via their transit light curves.