The sub-Jupiter mass transiting exoplanet WASP-11b

TL;DR

This paper reports the discovery and characterization of a sub-Jupiter mass exoplanet, WASP-11b, transiting a relatively faint K3V star, with detailed measurements of its mass, radius, and orbital parameters, contributing to the understanding of low-mass exoplanets.

Contribution

First detailed characterization of a sub-Jupiter mass exoplanet transiting a small, low-luminosity star, expanding knowledge of such systems.

Findings

WASP-11b has a mass of 0.53 M_J and radius of 0.91 R_J.

The host star is a K3V type with T_eff=4800K.

WASP-11b is among the least irradiated transiting exoplanets.

Abstract

We report the discovery of a sub-Jupiter mass exoplanet transiting a magnitude V=11.7 host star 1SWASP J030928.54+304024.7. A simultaneous fit to the transit photometry and radial-velocity measurements yield a planet mass M_p=0.53+-0.07M_J, radius R_p=0.91^{+0.06}_{-0.03}R_J and an orbital period of 3.722465^{+0.000006}_{-0.000008} days. The host star is of spectral type K3V, with a spectral analysis yielding an effective temperature of 4800+-100K and log g=4.45+-0.2. It is amongst the smallest, least massive and lowest luminosity stars known to harbour a transiting exoplanet. WASP-11b is the third least strongly irradiated transiting exoplanet discovered to date, experiencing an incident flux F_p=1.9x10^8 erg s^{-1} cm^{-2} and having an equilibrium temperature T_eq=960+-70K.