The Unusual M-dwarf Warm Jupiter TOI-1899 b: Refinement of Orbital and Planetary Parameters

Lin, Andrea S. J.; Libby-Roberts, Jessica E.; Alvarado-Montes, Jaime A.; Canas, Caleb I.; Kanodia, Shubham; Han, Te; Hebb, Leslie; Jensen, Eric L. N.; Mahadevan, Suvrath; Powers, Luke C.; Swaby, Tera N.; Wisniewski, John; Beard, Corey; Bender, Chad F.; Blake, Cullen H.; Cochran, William D.; Diddams, Scott A.; Frazier, Robert C.; Fredrick, Connor; Gully-Santiago, Michael; Halverson, Samuel; Logsdon, Sarah E.; McElwain, Michael W.; Morley, Caroline; Ninan, Joe P.; Rajagopal, Jayadev; Ramsey, Lawrence W.; Robertson, Paul; Roy, Arpita; Schwab, Christian; Stefansson, Guomundur; Stevens, Daniel J.; Terrien, Ryan C.; Wright, Jason T.
2023
ASTRONOMICAL JOURNAL
DOI
10.3847/1538-3881/ace1ef
TOI-1899 b is a rare exoplanet, a temperate warm Jupiter orbiting an M dwarf, first discovered by Canas et al. (2020) from a TESS single-transit event. Using new radial velocities (RVs) from the precision RV spectrographs HPF and NEID, along with additional TESS photometry and ground-based transit follow-up, we are able to derive a much more precise orbital period of P = 29.090312(-0.000035)(+0.000036) days, along with a radius of R-p = 0.99 +/- 0.03 R-J. We have also improved the constraints on planet mass, M-p = 0.67 +/- 0.04 M-J, and eccentricity, which is consistent with a circular orbit at 2 sigma (e = 0.044(-0.027)(+0.029)). TOI-1899 b occupies a unique region of parameter space as the coolest known (T-eq approximate to 380 K) Jovian-sized transiting planet around an M dwarf; we show that it has great potential to provide clues regarding the formation and migration mechanisms of these rare gas giants through transmission spectroscopy with JWST, as well as studies of tidal evolution.