A Transiting Warm Giant Planet around the Young Active Star TOI-201
Trifonov, Trifon; Henning, Thomas; Latham, David W.; Jordán, Andrés; Kossakowski, Diana; Brahm, Rafael; Kane, Stephen R.; Wittenmyer, Robert A.; Horner, Jonathan; Hobson, Melissa J.; Espinoza, Nestor; Schlecker, Martin; Collins, Karen A.; Wohler, Bill; Ricker, George R.; Winn, Joshua N.; Jenkins, Jon M.; Seager, S.; Shporer, Avi; Udry, Stéphane; Bowler, Brendan P.; Smith, Alexis M. S.; Twicken, Joseph D.; Bryant, Edward M.; Daylan, Tansu; Bouchy, François; Nielsen, Louise D.; Plavchan, Peter; Zucker, Shay; Sarkis, Paula; Tinney, C. G.; Huang, Chelsea; Kielkopf, John; Okumura, Jack; Wright, Duncan J.; Grieves, Nolan; McLean, Brian; Thorngren, Daniel; Shahaf, Sahar; Mengel, Matthew W.; Briegal, Joshua T.; Jones, Matias; Unger, Nicolas; Rojas, Felipe; West, Richard; Torres, Pascal; Addison, Brett; Binnenfeld, Avraham; Tilbrook, Rosanna
Chile, United States, Germany, Canada, Israel, Australia, Switzerland, United Kingdom
Abstract
We present the confirmation of the eccentric warm giant planet TOI-201 b, first identified as a candidate in Transiting Exoplanet Survey Satellite photometry (Sectors 1-8, 10-13, and 27-28) and confirmed using ground-based photometry from Next Generation Transit Survey and radial velocities from FEROS, HARPS, CORALIE, and MINERVA-Australis. TOI-201 b orbits a young ( ${0.87}_{-0.49}^{+0.46}\,\mathrm{Gyr}$ ) and bright (V = 9.07 mag) F-type star with a 52.9781 day period. The planet has a mass of ${0.42}_{-0.03}^{+0.05}\,{M}_{{\rm{J}}}$ , a radius of ${1.008}_{-0.015}^{+0.012}\,{R}_{{\rm{J}}}$ , and an orbital eccentricity of ${0.28}_{-0.09}^{+0.06};$ it appears to still be undergoing fairly rapid cooling, as expected given the youth of the host star. The star also shows long-term variability in both the radial velocities and several activity indicators, which we attribute to stellar activity. The discovery and characterization of warm giant planets such as TOI-201 b are important for constraining formation and evolution theories for giant planets.