WASP-42 b and WASP-49 b: two new transiting sub-Jupiters

We report the discovery of two new transiting planets from the WASP survey. WASP-42 b is a 0.500 ± 0.035 M_J planet orbiting a K1 star at a separation of 0.0548 ± 0.0017 AU with a period of 4.9816872 ± 7.3 × 10^-6 days. The radius of WASP-42 b is 1.080 ± 0.057 R_J while its equilibrium temperature is T_eq = 995 ± 34 K. We detect some evidence for a small but non-zero eccentricity of e = 0.060 ± 0.013. WASP-49 b is a 0.378 ± 0.027 M_J planet around an old G6 star. It has a period of 2.7817387 ± 5.6 × 10^-6 days and a separation of 0.0379 ± 0.0011 AU. This planet is slightly bloated, having a radius of 1.115 ± 0.047 R_J and an equilibrium temperature of T_eq = 1369 ± 39 K. Both planets have been followed up photometrically, and in total we have obtained 5 full and one partial transit light curves of WASP-42 and 4 full and one partial light curves of WASP-49 using the Euler-Swiss, TRAPPIST and Faulkes South telescopes.

Based on photometric observations made with WASP-South, EulerCam on the Euler-Swiss telescope, the Belgian TRAPPIST telescope, the Faulkes South Telescope and spectroscopic observations obtained with CORALIE on the Euler-Swiss telescope and HARPS on the ESO 3.6 m telescope (Prog. ID: 087.C-0649).The photometric time series and radial velocity data in this work are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/544/A72