HAT-P-25b: A hot-Jupiter transiting a moderately faint G star

Abstract

We report the discovery of HAT-P-25b, a transiting extrasolar planet orbiting the V = 13.19 G5 dwarf star GSC 1788-01237, with a period P = 3.652836 0.000019 days, transit epoch Tc = 2455176.85173 0.00047 (BJD - barycentric Julian dates throughout the paper are calculated from Coordinated Universal Time, UTC), and transit duration 0.1174 0.0017days. The host star has a mass of 1.01 0.03 M, radius of 0.96+0.05- 0.04 R, effective temperature 5500 80K, and metallicity [Fe/H] = +0.31 0.08. The planetary companion has a mass of 0.567 0.022M J and radius of 1.190+0.081- 0.056R J yielding a mean density of 0.42 0.07 g cm-3. © 2012. The American Astronomical Society. All rights reserved.