@article{1e4e63bb83944ad88fafe97075c45012,
title = "TESS Hunt for Young and Maturing Exoplanets (THYME). VI. An 11 Myr Giant Planet Transiting a Very-low-mass Star in Lower Centaurus Crux",
abstract = "Mature super-Earths and sub-Neptunes are predicted to be ≃ Jovian radius when younger than 10 Myr. Thus, we expect to find 5-15 R planets around young stars even if their older counterparts harbor none. We report the discovery and validation of TOI 1227b, a 0.85 ± 0.05 R J (9.5 R) planet transiting a very-low-mass star (0.170 ± 0.015 M) every 27.4 days. TOI 1227's kinematics and strong lithium absorption confirm that it is a member of a previously discovered subgroup in the Lower Centaurus Crux OB association, which we designate the Musca group. We derive an age of 11 ± 2 Myr for Musca, based on lithium, rotation, and the color-magnitude diagram of Musca members. The TESS data and ground-based follow-up show a deep (2.5\%) transit. We use multiwavelength transit observations and radial velocities from the IGRINS spectrograph to validate the signal as planetary in nature, and we obtain an upper limit on the planet mass of ≃0.5 M J. Because such large planets are exceptionally rare around mature low-mass stars, we suggest that TOI 1227b is still contracting and will eventually turn into one of the more common <5 R planets.",
author = "Mann, \{Andrew W.\} and Wood, \{MacKenna L.\} and Schmidt, \{Stephen P.\} and Barber, \{Madyson G.\} and Owen, \{James E.\} and Tofflemire, \{Benjamin M.\} and Newton, \{Elisabeth R.\} and Mamajek, \{Eric E.\} and Bush, \{Jonathan L.\} and Mace, \{Gregory N.\} and Kraus, \{Adam L.\} and Thao, \{Pa Chia\} and Andrew Vanderburg and Joe Llama and Johns-Krull, \{Christopher M.\} and L. Prato and Stahl, \{Asa G.\} and Tang, \{Shih Yun\} and Fields, \{Matthew J.\} and Collins, \{Karen A.\} and Collins, \{Kevin I.\} and Tianjun Gan and Jensen, \{Eric L.N.\} and Jacob Kamler and Schwarz, \{Richard P.\} and Elise Furlan and Gnilka, \{Crystal L.\} and Howell, \{Steve B.\} and Lester, \{Kathryn V.\} and Owens, \{Dylan A.\} and Olga Suarez and Djamel Mekarnia and Tristan Guillot and Lyu Abe and Triaud, \{Amaury H.M.J.\} and Johnson, \{Marshall C.\} and Milburn, \{Reilly P.\} and Rizzuto, \{Aaron C.\} and Quinn, \{Samuel N.\} and Ronan Kerr and Ricker, \{George R.\} and Roland Vanderspek and Latham, \{David W.\} and Sara Seager and Winn, \{Joshua N.\} and Jenkins, \{Jon M.\} and Guerrero, \{Natalia M.\} and Avi Shporer and Schlieder, \{Joshua E.\} and Brian McLean and Bill Wohler",
note = "Publisher Copyright: {\textcopyright} 2022. The American Astronomical Society. All rights reserved.",
year = "2022",
month = apr,
day = "1",
doi = "10.3847/1538-3881/ac511d",
language = "English (US)",
volume = "163",
journal = "Astronomical Journal",
issn = "0004-6256",
publisher = "American Astronomical Society",
number = "4",
}