학술논문
TOI-2109b: An Ultrahot Gas Giant on a 16 hr Orbit
Document Type
Working Paper
Author
Wong, Ian; Shporer, Avi; Zhou, George; Kitzmann, Daniel; Komacek, Thaddeus D.; Tan, Xianyu; Tronsgaard, René; Buchhave, Lars A.; Vissapragada, Shreyas; Greklek-McKeon, Michael; Rodriguez, Joseph E.; Ahlers, John P.; Quinn, Samuel N.; Furlan, Elise; Howell, Steve B.; Bieryla, Allyson; Heng, Kevin; Knutson, Heather A.; Collins, Karen A.; McLeod, Kim K.; Berlind, Perry; Brown, Peyton; Calkins, Michael L.; de Leon, Jerome P.; Esparza-Borges, Emma; Esquerdo, Gilbert A.; Fukui, Akihiko; Gan, Tianjun; Girardin, Eric; Gnilka, Crystal L.; Ikoma, Masahiro; Jensen, Eric L. N.; Kielkopf, John; Kodama, Takanori; Kurita, Seiya; Lester, Kathryn V.; Lewin, Pablo; Marino, Giuseppe; Murgas, Felipe; Narita, Norio; Pallé, Enric; Schwarz, Richard P.; Stassun, Keivan G.; Tamura, Motohide; Watanabe, Noriharu; Benneke, Björn; Ricker, George R.; Latham, David W.; Vanderspek, Roland; Seager, Sara; Winn, Joshua N.; Jenkins, Jon M.; Caldwell, Douglas A.; Fong, William; Huang, Chelsea X.; Mireles, Ismael; Schlieder, Joshua E.; Shiao, Bernie; Villaseñor, Jesus Noel
Source
AJ, 162, 256 (2021)
Subject
Language
Abstract
We report the discovery of an ultrahot Jupiter with an extremely short orbital period of $0.67247414\,\pm\,0.00000028$ days ($\sim$16 hr). The $1.347 \pm 0.047$ $R_{\rm Jup}$ planet, initially identified by the Transiting Exoplanet Survey Satellite (TESS) mission, orbits TOI-2109 (TIC 392476080): a $T_{\rm eff} \sim 6500$ K F-type star with a mass of $1.447 \pm 0.077$ $M_{\rm Sun}$, a radius of $1.698 \pm 0.060$ $R_{\rm Sun}$, and a rotational velocity of $v\sin i_* = 81.9 \pm 1.7$ km s$^{-1}$. The planetary nature of TOI-2109b was confirmed through radial velocity measurements, which yielded a planet mass of $5.02 \pm 0.75$ $M_{\rm Jup}$. Analysis of the Doppler shadow in spectroscopic transit observations indicates a well-aligned system, with a sky-projected obliquity of $\lambda = 1\overset{\circ}{.}7 \pm 1\overset{\circ}{.}7$. From the TESS full-orbit light curve, we measured a secondary eclipse depth of $731 \pm 46$ ppm, as well as phase-curve variations from the planet's longitudinal brightness modulation and ellipsoidal distortion of the host star. Combining the TESS-band occultation measurement with a $K_s$-band secondary eclipse depth ($2012 \pm 80$ ppm) derived from ground-based observations, we find that the dayside emission of TOI-2109b is consistent with a brightness temperature of $3631 \pm 69$ K, making it the second hottest exoplanet hitherto discovered. By virtue of its extreme irradiation and strong planet-star gravitational interaction, TOI-2109b is an exceptionally promising target for intensive follow-up studies using current and near-future telescope facilities to probe for orbital decay, detect tidally driven atmospheric escape, and assess the impacts of H$_2$ dissociation and recombination on the global heat transport.
Comment: 30 pages, 17 figures, published in AJ
Comment: 30 pages, 17 figures, published in AJ