Radial velocity and photometry of TOI-677

Such sources pose a challenge for models of giant planet formation, which must account for the excitation of high eccentricities without large changes in the orbital inclination. In this work, we present a new Rossiter-McLaughlin measurement of the tidally detached warm Jupiter TOI-677b, obtained using high-precision radial velocity observations with Magellan's Planet Finder Spectrograph (PFS).

Combined with previously published observations from the Very Large Telescope's ESPRESSO spectrograph, we derive one of the most precisely constrained sky-projected spin-orbit angle measurements to date for an exoplanet. The combined fit offers a refined set of self-consistent parameters, including a low sky-projected stellar obliquity of {lambda}=3.2_-1.5_^+1.6^deg and a moderately high eccentricity of e=0.460_-0.018_^+0.019^, which further constrain the puzzling architecture of this system.