TOI-954 b and K2-329 b: Short-period Saturn-mass Planets that Test whether Irradiation Leads to Inflation
Date Issued
2021
Author(s)
Sha, Lizhou
Huang, Chelsea X.
Shporer, Avi
Rodriguez, Joseph E.
Vanderburg, Andrew
Brahm, Rafael
Hagelberg, Janis
Matthews, Elisabeth C.
Ziegler, Carl
Livingston, John H.
Stassun, Keivan G.
Wright, Duncan J.
Crane, Jeffrey D.
Espinoza, Nestor
Bouchy, Francois
Bakos, Gaspar A.
Collins, Karen A.
Zhou, George
Bieryla, Allyson
Hartman, Joel D.
Wittenmyer, Robert A.
Nielsen, Louise D.
Plavchan, Peter
Bayliss, Daniel
Sarkis, Paula
Tan, Thiam-Guan
Cloutier, Ryan
Mancini, Luigi
Jordan, Andres
Wang, Sharon
Henning, Thomas
Narita, Norio
Penev, Kaloyan
Teske, Johanna K.
Kane, Stephen R.
Mann, Andrew W.
Addison, Brett C.
Tamura, Motohide
Horner, Jonathan
Barbieri, Mauro
Burt, Jennifer A.
Diaz, Matias R.
Crossfield, Ian J. M.
Dragomir, Diana
Drass, Holger
Feinstein, Adina D.
Zhang, Hui
Hart, Rhodes
Kielkopf, John F.
Jensen, Eric L. N.
Montet, Benjamin T.
Ottoni, Gael
Schwarz, Richard P.
Rojas, Felipe
Nespral, David
Torres, Pascal
Mengel, Matthew W.
Udry, Stephane
Zapata, Abner
Snoddy, Erin
Okumura, Jack
Ricker, George R.
Vanderspek, Roland K.
Latham, David W.
Winn, Joshua N.
Seager, Sara
Jenkins, Jon M.
Colon, Knicole D.
Henze, Christopher E.
Krishnamurthy, Akshata
Ting, Eric B.
Vezie, Michael
Villanueva, Steven
DOI
http://dx.doi.org/10.3847/1538-3881/abd187
Abstract
We report the discovery of two short-period Saturn-mass planets, one transiting the G subgiant TOI-954 (TIC 44792534, V = 10.343, T = 9.78) observed in TESS sectors 4 and 5 and one transiting the G dwarf K2-329 (EPIC 246193072, V = 12.70, K = 10.67) observed in K2 campaigns 12 and 19. We confirm and characterize these two planets with a variety of ground-based archival and follow-up observations, including photometry, reconnaissance spectroscopy, precise radial velocity, and high-resolution imaging. Combining all available data, we find that TOI-954 b has a radius of 0.852(-0.062)(+0.053) R-J and a mass of 0.174(-0.017)(+0.018) M-J and is in a 3.68 day orbit, while K2-329 b has a radius of 0.774(-0.024)(+0.026) R-J and a mass if 0.260(-0.022)(+0.020) M-J and is in a 12.46 day orbit. As TOI-954 b is 30 times more irradiated than K2-329 b but more or less the same size, these two planets provide an opportunity to test whether irradiation leads to inflation of Saturn-mass planets and contribute to future comparative studies that explore Saturn-mass planets at contrasting points in their lifetimes.