학술논문
Three low-mass companions around aged stars discovered by TESS
Document Type
Working Paper
Author
Lin, Zitao; Gan, Tianjun; Wang, Sharon X.; Shporer, Avi; Rabus, Markus; Zhou, George; Psaridi, Angelica; Bouchy, François; Bieryla, Allyson; Latham, David W.; Mao, Shude; Stassun, Keivan G.; Hellier, Coel; Howell, Steve B.; Ziegler, Carl; Caldwell, Douglas A.; Clark, Catherine A.; Collins, Karen A.; Curtis, Jason L.; Faherty, Jacqueline K.; Gnilka, Crystal L.; Grunblatt, Samuel K.; Jenkins, Jon M.; Johnson, Marshall C.; Law, Nicholas; Lendl, Monika; Littlefield, Colin; Lund, Michael B.; Lund, Mikkel N.; Mann, Andrew W.; McDermott, Scott; Mishra, Lokesh; Mounzer, Dany; Paegert, Martin; Pritchard, Tyler; Ricker, George R.; Seager, Sara; Srdoc, Gregor; Sun, Qinghui; Tang, Jiaxin; Udry, Stéphane; Vanderspek, Roland; Watanabe, David; Winn, Joshua N.; Yu, Jie
Source
Subject
Language
Abstract
We report the discovery of three transiting low-mass companions to aged stars: a brown dwarf (TOI-2336b) and two objects near the hydrogen burning mass limit (TOI-1608b and TOI-2521b). These three systems were first identified using data from the Transiting Exoplanet Survey Satellite (TESS). TOI-2336b has a radius of $1.05\pm 0.04\ R_J$, a mass of $69.9\pm 2.3\ M_J$ and an orbital period of 7.71 days. TOI-1608b has a radius of $1.21\pm 0.06\ R_J$, a mass of $90.7\pm 3.7\ M_J$ and an orbital period of 2.47 days. TOI-2521b has a radius of $1.01\pm 0.04\ R_J$, a mass of $77.5\pm 3.3\ M_J$ and an orbital period of 5.56 days. We found all these low-mass companions are inflated. We fitted a relation between radius, mass and incident flux using the sample of known transiting brown dwarfs and low-mass M dwarfs. We found a positive correlation between the flux and the radius for brown dwarfs and for low-mass stars that is weaker than the correlation observed for giant planets. We also found that TOI-1608 and TOI-2521 are very likely to be spin-orbit synchronized, leading to the unusually rapid rotation of the primary stars considering their evolutionary stages. Our estimates indicate that both systems have much shorter spin-orbit synchronization timescales compared to their ages. These systems provide valuable insights into the evolution of stellar systems with brown dwarf and low-mass stellar companions influenced by tidal effects.
Comment: 23 pages, 15 figures; Published in MNRAS
Comment: 23 pages, 15 figures; Published in MNRAS