We report the discovery of KELT-3b, a moderately inflated transiting hot Jupiter with a mass of 1.477 (-0.067, +0.066) M_J, and radius of 1.345 +/- 0.072 R_J, with an orbital period of 2.7033904 +/- 0.000010 days. The host star, KELT-3, is a V=9.8 late F star with M_* = 1.278 (-0.061, +0.063) M_sun, R_* = 1.472 (-0.067, +0.065) R_sun, T_eff = 6306 (-49, +50) K, log(g) = 4.209 (-0.031, +0.033), and [Fe/H] = 0.044 (-0.082, +0.080), and has a likely proper motion companion. KELT-3b is the third transiting exoplanet discovered by the KELT survey, and is orbiting one of the 20 brightest known transiting planet host stars, making it a promising candidate for detailed characterization studies. Although we infer that KELT-3 is significantly evolved, a preliminary analysis of the stellar and orbital evolution of the system suggests that the planet has likely always received a level of incident flux above the empirically-identified threshold for radius inflation suggested by Demory & Seager (2011).
@article{arxiv.1211.1031,
title = {KELT-3b: A Hot Jupiter Transiting a V=9.8 Late-F Star},
author = {Joshua Pepper and Robert J. Siverd and Thomas G. Beatty and B. Scott Gaudi and Keivan G. Stassun and Jason Eastman and Karen Collins and David W. Latham and Allyson Bieryla and Lars A. Buchhave and Eric L. N. Jensen and Mark Manner and Kaloyan Penev and Justin R. Crepp and Phillip A. Cargile and Saurav Dhital and Michael L. Calkins and Gilbert A. Esquerdo and Perry Berlind and Benjamin J. Fulton and Rachel Street and Bo Ma and Jian Ge and Ji Wang and Qingqing Mao and Alexander J. W. Richert and Andrew Gould and Darren L. DePoy and John F. Kielkopf and Jennifer L. Marshall and Richard W. Pogge and Robert P. Stefanik and Mark Trueblood and Patricia Trueblood},
journal= {arXiv preprint arXiv:1211.1031},
year = {2015}
}