HATS-59b,c: A Transiting Hot Jupiter and a Cold Massive Giant Planet Around a Sun-Like Star

Abstract

We report the first discovery of a multi-planetary system by the HATSouth network, HATS-59b,c, a planetary system with an inner transiting hot Jupiter and an outer cold massive giant planet, which was detected via radial velocity. The inner transiting planet, HATS-59b, is on an eccentric orbit with $e=0.129\pm 0.049$, orbiting a $V=13.951\pm 0.030$ mag solar-like star ($M_{\ast }=1.038\pm 0.039M_{\odot }$, and $R_{\ast }=1.036\pm 0.067R_{\odot }$) with a period of $5.416077\pm 0.000017$ days. The outer companion, HATS-59c is on a circular orbit with $m\sin i=12.8\pm 1.1M_{\mathrm{J}}$, and a period of $1422\pm 14$ days. The inner planet has a mass of $0.806\pm 0.069M_{\mathrm{J}}$ and a radius of $1.126\pm 0.077M_{\mathrm{J}}$, yielding a density of $0.70\pm 0.16\mathrm{g}\mathrm{c}{\mathrm{m}}^{-3}$. Unlike most of the planetary systems that include only a single hot Jupiter, HATS-59b,c includes, in addition to the transiting hot Jupiter, a massive outer companion. The architecture of this system is valuable for understanding planet migration.

12 pages, 9 figures, submitted to AJ. For a short discussion, see https://sites.google.com/view/paulasarkis/research/hats-59