HATS-47b, HATS-48Ab, HATS-49b and HATS-72b: Four Warm Giant Planets Transiting K Dwarfs

Abstract

We report the discovery of four transiting giant planets around K dwarfs. The planets HATS-47b, HATS-48Ab, HATS-49b, and HATS-72b have masses of $0.369_{-0.021}^{+0.031}$ $M_J$, $0.243_{-0.030}^{+0.022}$ $M_J$, $0.353_{-0.027}^{+0.038}$ $M_J$ and $0.1254\pm 0.0039$ $M_J$, respectively, and radii of $1.117\pm 0.014$ $R_J$, $0.800\pm 0.015$ $R_J$, $0.765\pm 0.013$ $R_J$, and $0.7224\pm 0.0032$ $R_J$, respectively. The planets orbit close to their host stars with orbital periods of $3.9228$ d, $3.1317$ d, $4.1480$ d and $7.3279$ d, respectively. The hosts are main sequence K dwarfs with masses of $0.674_{-0.012}^{+0.016}$ $M_{\odot }$, $0.7279\pm 0.0066$ $M_{\odot }$, $0.7133\pm 0.0075$ $M_{\odot }$, and $0.7311\pm 0.0028$ $M_{\odot }$ and with $V$-band magnitudes of $V=14.829\pm 0.010$, $14.35\pm 0.11$, $14.998\pm 0.040$ and $12.469\pm 0.010$. The Super-Neptune HATS-72b (a.k.a.\ WASP-191b and TOI 294.01) was independently identified as a transiting planet candidate by the HATSouth, WASP and TESS surveys, and we present a combined analysis of all of the data gathered by each of these projects (and their follow-up programs). An exceptionally precise mass is measured for HATS-72b thanks to high-precision radial velocity (RV) measurements obtained with VLT/ESPRESSO, FEROS, HARPS and Magellan/PFS. We also incorporate TESS observations of the warm Saturn-hosting systems HATS-47 (a.k.a. TOI 1073.01), HATS-48A and HATS-49. HATS-47 was independently identified as a candidate by the TESS team, while the other two systems were not previously identified from the TESS data. The RV orbital variations are measured for these systems using Magellan/PFS. HATS-48A has a resolved $5.{}^{\prime \prime }4$ neighbor in Gaia~DR2, which is a common-proper-motion binary star companion to HATS-48A with a mass of $0.22$ $M_{\odot }$ and a current projected physical separation of $\sim$1,400 au.

Accepted for publication in AJ. 32 pages, 14 figures, 7 tables