Three hot-Jupiters on the upper edge of the mass-radius distribution: WASP-177, WASP-181, and WASP-183

We present the discovery of three transiting planets from the WASP survey, two hot-Jupiters: WASP-177 b (∼0.5 M_Jup, ∼1.6 R_Jup) in a 3.07-d orbit of a V = 12.6 K2 star, WASP-183 b (∼0.5 M_Jup, ∼1.5 R_Jup) in a 4.11-d orbit of a V = 12.8 G9/K0 star; and one hot-Saturn planet WASP-181 b (∼0.3 M_Jup, ∼1.2 R_Jup) in a 4.52-d orbit of a V = 12.9 G2 star. Each planet is close to the upper bound of mass-radius space and has a scaled semimajor axis, a/R_*, between 9.6 and 12.1. These lie in the transition between systems that tend to be in orbits that are well aligned with their host-star's spin and those that show a higher dispersion.