학술논문
TESS Hunt for Young and Maturing Exoplanets (THYME) X: a two-planet system in the 210 Myr MELANGE-5 Association
Document Type
Working Paper
Author
Thao, Pa Chia; Mann, Andrew W.; Barber, Madyson G.; Kraus, Adam L.; Tofflemire, Benjamin M.; Bush, Jonathan L.; Wood, Mackenna L.; Collins, Karen A.; Vanderburg, Andrew; Quinn, Samuel N.; Zhou, George; Newton, Elisabeth R.; Ziegler, Carl; Law, Nicholas; Barkaoui, Khalid; Pozuelos, Francisco J.; Timmermans, Mathilde; Gillon, Michaël; Jehin, Emmanuël; Schwarz, Richard P.; Gan, Tianjun; Shporer, Avi; Horne, Keith; Sefako, Ramotholo; Suarez, Olga; Mekarnia, Djamel; Guillot, Tristan; Abe, Lyu; Triaud, Amaury H. M. J.; Radford, Don J.; Murillo, Ana Isabel Lopez; Ricker, George R.; Winn, Joshua N.; Jenkins, Jon M.; Bouma, Luke G.; Fausnaugh, Michael; Guerrero, Natalia M.; Kunimoto, Michelle
Source
Subject
Language
Abstract
Young (<500 Myr) planets are critical to studying how planets form and evolve. Among these young planetary systems, multi-planet configurations are particularly useful as they provide a means to control for variables within a system. Here, we report the discovery and characterization of a young planetary system, TOI-1224. We show that the planet-host resides within a young population we denote as MELANGE-5 . By employing a range of age-dating methods -- isochrone fitting, lithium abundance analysis, gyrochronology, and Gaia excess variability -- we estimate the age of MELANGE-5 to be 210$\pm$27 Myr. MELANGE-5 is situated in close proximity to previously identified younger (80 -110 Myr) associations, Crius 221 and Theia 424/Volans-Carina, motivating further work to map out the group boundaries. In addition to a planet candidate detected by the TESS pipeline and alerted as a TESS Object of Interest, TOI-1224 b, we identify a second planet, TOI-1224 c, using custom search tools optimized for young stars (Notch and LOCoR). We find the planets are 2.10$\pm$0.09$R_\oplus$ and 2.88$\pm$0.10$R_\oplus$ and orbit their host star every 4.18 and 17.95 days, respectively. With their bright ($K$=9.1 mag), small ($R_{*}$=0.44R$_{\odot}$), and cool ($T_{eff}$ =3326K) host star, these planets represent excellent candidates for atmospheric characterization with JWST.
Comment: Accepted for publication in The Astronomical Journal; 33 pages, 17 figures, 9 tables
Comment: Accepted for publication in The Astronomical Journal; 33 pages, 17 figures, 9 tables