2017A&A...599A...3L

We report three newly discovered exoplanets from the SuperWASP survey. WASP-127b is a heavily inflated super-Neptune of mass 0.18±0.02M_J and radius 1.37±0.04R_J. This is one of the least massive planets discovered by the WASP project. It orbits a bright host star (V_mag=10.16) of spectral type G5 with a period of 4.17-days. WASP-127b is a low-density planet that has an extended atmosphere with a scale height of 2500±400km, making it an ideal candidate for transmission spectroscopy. WASP-136b and WASP-138b are both hot Jupiters with mass and radii of 1.51±0.08M_J and 1.38±0.16R_J, and 1.22±0.08M_J and 1.09±0.05R_J, respectively. WASP-136b is in a 5.22-day orbit around an F9 subgiant star with a mass of 1.41±0.07M_☉ and a radius of 2.21±0.22R_☉. The discovery of WASP-136b could help constrain the characteristics of the giant planet population around evolved stars. WASP-138b orbits an F7 star with a period of 3.63 days. Its radius agrees with theoretical values from standard models, suggesting the presence of a heavy element core with a mass of ∼10M_⊕. The discovery of these new planets helps in exploring the diverse compositional range of short-period planets, and will aid our understanding of the physical characteristics of both gas giants and low-density planets.