HATS-39b, HATS-40b, HATS-41b, and HATS-42b: Three Inflated Hot Jupiters and a Super-Jupiter Transiting F Stars

TL;DR

This paper reports the discovery of four transiting hot Jupiters around F dwarf stars, highlighting their diverse masses, radii, and orbital characteristics, with implications for planetary formation and evolution.

Contribution

The paper presents four new hot Jupiter discoveries from the HATSouth survey, including a super-Jupiter and an inflated planet, expanding understanding of planetary diversity.

Findings

HATS-39b has an inflated radius of 1.57 R_J.

HATS-41b is a massive 9.7 M_J planet with an eccentric orbit.

HATS-40b and HATS-42b have similar radii but different masses.

Abstract

We report the discovery of four transiting hot Jupiters from the HATSouth survey: HATS-39b, HATS-40b, HATS41b and HATS-42b. These discoveries add to the growing number of transiting planets orbiting moderately bright (12.5 < V < 13.7) F dwarf stars on short (2-5 day) periods. The planets have similar radii, ranging from 1.33(+0.29/-0.20) R_J for HATS-41b to 1.58(+0.16/-0.12) R_J for HATS-40b. Their masses and bulk densities, however, span more than an order of magnitude. HATS-39b has a mass of 0.63 +/- 0.13 M_J, and an inflated radius of 1.57 +/- 0.12 R_J, making it a good target for future transmission spectroscopic studies. HATS-41b is a very massive 9.7 +/- 1.6 M_J planet and one of only a few hot Jupiters found to date with a mass over 5 M_J. This planet orbits the highest metallicity star ([Fe/H] = 0.470 +/- 0.010) known to host a transiting planet and is also likely on an eccentric orbit. The high mass, coupled with a relatively young age (1.34 +0.31/-0.51 Gyr) for the host star, are factors that may explain why this planet's orbit has not yet circularised.