HAT-P-6b: A Hot Jupiter Transiting a Bright F Star

Abstract

In the ongoing HATNet survey we have detected a giant planet, with radius 1.33 +/- 0.06 RJup and mass 1.06+/-0.12 MJup, transiting the bright (V=10.5) star GSC 03239-00992. The planet is in a circular orbit with period 3.852985+/-0.000005 days and midtransit epoch 2,454,035.67575 +/- 0.00028 (HJD). The parent star is a late F star with mass 1.29+/-0.06 Msolar, radius 1.46+/-0.06 Rsolar, Teff~6570+/-80 K, [Fe/H]=-0.13+/-0.08, and age ~2.3+0.5-0.7 Gyr. With this radius and mass, HAT-P-6b has somewhat larger radius than theoretically expected. We describe the observations and their analysis to determine physical properties of the HAT-P-6 system, and briefly discuss some implications of this finding. Based in part on observations obtained at the W. M. Keck Observatory, which is operated by the University of California and the California Institute of Technology. Keck time has been in part granted by NASA (run N162Hr) and NOAO (run A285Hr).