WASP-5b: a dense, very-hot Jupiter transiting a 12th-mag Southern-hemisphere star

TL;DR

The paper reports the discovery and detailed characterization of WASP-5b, a very-hot, dense Jupiter-mass exoplanet orbiting a 12th magnitude star, providing precise measurements of its physical properties and orbital parameters.

Contribution

It presents the first detailed measurements of WASP-5b's mass, radius, and density, highlighting its status as the densest known Jovian-mass planet with a very short orbital period.

Findings

WASP-5b has a mass of approximately 1.58 Jupiter masses.

The planet's radius is about 1.09 Jupiter radii.

WASP-5b's density is notably high at around 1.22 times that of Jupiter.

Abstract

We report the discovery of WASP-5b, a Jupiter-mass planet orbiting a 12th-mag G-type star in the Southern hemisphere. The 1.6-d orbital period places WASP-5b in the class of very-hot Jupiters and leads to a predicted equilibrium temperature of 1750 K. WASP-5b is the densest of any known Jovian-mass planet, being a factor seven denser than TrES-4, which is subject to similar stellar insolation, and a factor three denser than WASP-4b, which has a similar orbital period. We present transit photometry and radial-velocity measurements of WASP-5 (= USNO-B1 0487-0799749), from which we derive the mass, radius and density of the planet: M_P = 1.58 +0.13 -0.08 M_J, R_P = 1.090 +0.094 -0.058 R_J and Rho_P = 1.22 +0.19 -0.24 Rho_J. The orbital period is P = 1.6284296 +0.0000048 -0.0000037 d and the mid-transit epoch is T_C (HJD) = 2454375.62466 +0.00026 -0.00025.