TY - JOUR
T1 - TESS Hunt for Young and Maturing Exoplanets (THYME). VII. Membership, Rotation, and Lithium in the Young Cluster Group-X and a New Young Exoplanet
AU - Newton, Elisabeth R.
AU - Rampalli, Rayna
AU - Kraus, Adam L.
AU - Mann, Andrew W.
AU - Curtis, Jason L.
AU - Vanderburg, Andrew
AU - Krolikowski, Daniel M.
AU - Huber, Daniel
AU - Petter, Grayson C.
AU - Bieryla, Allyson
AU - Tofflemire, Benjamin M.
AU - Thao, Pa Chia
AU - Wood, Mackenna L.
AU - Kerr, Ronan
AU - Safanov, Boris S.
AU - Strakhov, Ivan A.
AU - Ciardi, David R.
AU - Giacalone, Steven
AU - Dressing, Courtney D.
AU - Gill, Holden
AU - Savel, Arjun B.
AU - Collins, Karen A.
AU - Brown, Peyton
AU - Murgas, Felipe
AU - Isogai, Keisuke
AU - Narita, Norio
AU - Palle, Enric
AU - Quinn, Samuel N.
AU - Eastman, Jason D.
AU - Fűrész, Gábor
AU - Shiao, Bernie
AU - Daylan, Tansu
AU - Caldwell, Douglas A.
AU - Ricker, George R.
AU - Vanderspek, Roland
AU - Seager, Sara
AU - Winn, Joshua N.
AU - Jenkins, Jon M.
AU - Latham, David W.
N1 - Publisher Copyright:
© 2022. The Author(s). Published by the American Astronomical Society.
PY - 2022/9/1
Y1 - 2022/9/1
N2 - The public, all-sky surveys Gaia and TESS provide the ability to identify new young associations and determine their ages. These associations enable study of planetary evolution by providing new opportunities to discover young exoplanets. A young association was recently identified by Tang et al. and Fürnkranz et al. using astrometry from Gaia (called “Group-X” by the former). In this work, we investigate the age and membership of this association, and we validate the exoplanet TOI 2048 b, which was identified to transit a young, late G dwarf in Group-X using photometry from TESS. We first identified new candidate members of Group-X using Gaia EDR3 data. To infer the age of the association, we measured rotation periods for candidate members using TESS data. The clear color-period sequence indicates that the association is the same age as the 300 ± 50 Myr old NGC 3532. We obtained optical spectra for candidate members that show lithium absorption consistent with this young age. Further, we serendipitously identify a new, small association nearby Group-X, which we call MELANGE-2. Lastly, we statistically validate TOI 2048 b, which is a 2.1 ± 0.2 R ⊕ radius planet on a 13.8-day orbit around its 300 Myr old host star.
AB - The public, all-sky surveys Gaia and TESS provide the ability to identify new young associations and determine their ages. These associations enable study of planetary evolution by providing new opportunities to discover young exoplanets. A young association was recently identified by Tang et al. and Fürnkranz et al. using astrometry from Gaia (called “Group-X” by the former). In this work, we investigate the age and membership of this association, and we validate the exoplanet TOI 2048 b, which was identified to transit a young, late G dwarf in Group-X using photometry from TESS. We first identified new candidate members of Group-X using Gaia EDR3 data. To infer the age of the association, we measured rotation periods for candidate members using TESS data. The clear color-period sequence indicates that the association is the same age as the 300 ± 50 Myr old NGC 3532. We obtained optical spectra for candidate members that show lithium absorption consistent with this young age. Further, we serendipitously identify a new, small association nearby Group-X, which we call MELANGE-2. Lastly, we statistically validate TOI 2048 b, which is a 2.1 ± 0.2 R ⊕ radius planet on a 13.8-day orbit around its 300 Myr old host star.
UR - http://www.scopus.com/inward/record.url?scp=85137413687&partnerID=8YFLogxK
U2 - 10.3847/1538-3881/ac8154
DO - 10.3847/1538-3881/ac8154
M3 - Article
AN - SCOPUS:85137413687
SN - 0004-6256
VL - 164
JO - Astronomical Journal
JF - Astronomical Journal
IS - 3
M1 - 115
ER -