WASP-37b: a 1.8 MJ exoplanet transiting a metal-poor star

TL;DR

This paper reports the discovery of WASP-37b, a hot Jupiter exoplanet transiting a metal-poor G-type star, providing insights into planet formation around low-metallicity stars.

Contribution

It presents the first detailed characterization of a transiting planet around a low-metallicity star, expanding understanding of planetary systems in such environments.

Findings

WASP-37b has a mass of 1.80 MJ and radius of 1.16 RJ.

The host star has a metallicity of [Fe/H] = -0.40.

WASP-37b orbits its star every 3.577 days.

Abstract

We report on the discovery of WASP-37b, a transiting hot Jupiter orbiting a mv = 12.7 G2-type dwarf, with a period of 3.577471 \pm 0.00001 d, transit epoch T0 = 2455338.6188 \pm 0.0006 (HJD), and a transit duration 0.1304 \pm 0.0018 d. The planetary companion has a mass Mp = 1.80 \pm 0.17 MJ and radius Rp = 1.16 \pm 0.07 RJ, yielding a mean density of 1.15 \pm 0.15 times that of Jupiter. From a spectral analysis and comparisons with stellar models, we find the host star has M* = 0.925 \pm 0.120 Msun, R* = 1.003 \pm 0.053 Rsun, Teff = 5800 \pm 150 K and [Fe/H] = -0.40 \pm 0.12. WASP-37 is therefore one of the lowest metallicity stars to host a transiting planet.