The Discovery of a Planetary Companion Interior to Hot Jupiter WASP-132 b
Torres, Guillermo; Vanderburg, Andrew; Latham, David W.; Stassun, Keivan G.; Berger, Travis A.; Ziegler, Carl; Lissauer, Jack J.; Collins, Karen A.; Ricker, George R.; Winn, Joshua N.; Jenkins, Jon M.; Seager, S.; Mann, Andrew W.; Colón, Knicole D.; Twicken, Joseph D.; Sefako, Ramotholo; Bouma, Luke G.; Schwarz, Richard P.; Law, Nicholas; Briceño, César; Kostov, Veselin; Falk, Ben; Hord, Benjamin J.; Silverstein, Michele L.
United States, South Africa, Chile
Abstract
Hot Jupiters are generally observed to lack close planetary companions, a trend that has been interpreted as evidence for high-eccentricity migration. We present the discovery and validation of WASP-132 c (TOI-822.02), a 1.85 ± 0.10 R ⊕ planet on a 1.01 day orbit interior to the hot Jupiter WASP-132 b. Transiting Exoplanet Survey Satellite and ground-based follow-up observations, in conjunction with vetting and validation analysis, enable us to rule out common astrophysical false positives and validate the observed transit signal produced by WASP-132 c as a planet. Running the validation tools vespa and TRICERATOPS on this signal yields false-positive probabilities of 9.02 × 10-5 and 0.0107, respectively. Analysis of archival CORALIE radial velocity data leads to a 3σ upper limit of 28.23 ms-1 on the amplitude of any 1.01 day signal, corresponding to a 3σ upper mass limit of 37.35 M ⊕. Dynamical simulations reveal that the system is stable within the 3σ uncertainties on the planetary and orbital parameters for timescales of ~100 Myr. The existence of a planetary companion near the hot Jupiter WASP-132 b makes the giant planet's formation and evolution via high-eccentricity migration highly unlikely. Being one of just a handful of nearby planetary companions to hot Jupiters, WASP-132 c carries with it significant implications for the formation of the system and hot Jupiters as a population.