WASP-104b and WASP-106b: Two transiting hot Jupiters in 1.75-day and 9.3-day orbits

Abstract

We have used the WASP survey to discover two exoplanetary systems, each consisting of a Jupiter-sized planet transiting an 11th-magnitude (V) main-sequence star. WASP-104b orbits its star in 1.75 d, whereas WASP-106b has the fourth-longest orbital period of any planet discovered by means of transits observed from the ground, orbiting every 9.29 d. Each planet is more massive than Jupiter (WASP-104b has a mass of 1.27 ± 0.05MJup, while WASP-106b has a mass of 1.93 ± 0.08MJup). Both planets are just slightly larger than Jupiter, with radii of 1.14 ± 0.04 and 1.09 ± 0.04RJup for WASP-104 and WASP-106, respectively. No significant orbital eccentricity is detected in either system, and while this is not surprising in the case of the short-period WASP-104b, it is interesting in the case of WASP-106b, because many otherwise similar planets are known to have eccentric orbits.