TOI-954 b and K2-329 b: Short-Period Saturn-Mass Planets that Test whether Irradiation Leads to Inflation
Creators: name: Sha, Lizhou
name: Huang, Chelsea X.
name: Shporer, Avi
name: Rodriguez, Joseph E.
name: Vanderburg, Andrew
name: Brahm, Rafael
name: Hagelberg, Janis
name: Matthews, Elisabeth C.
name: Ziegler, Carl
name: Livingston, John H.
name: Stassun, Keivan G.
name: Wright, Duncan J.
name: Crane, Jeffrey D.
name: Espinoza, Néstor
name: Bouchy, François
name: Bakos, Gáspár Á.
name: Collins, Karen A.
name: Zhou, George
name: Bieryla, Allyson
name: Hartman, Joel D.
name: Wittenmyer, Robert A.
name: Nielsen, Louise D.
name: Plavchan, Peter
name: Bayliss, Daniel
name: Sarkis, Paula
name: Tan, Thiam-Guan
name: Cloutier, Ryan
name: Mancini, Luigi
name: Jordán, Andrés
name: Wang, Sharon
name: Henning, Thomas
name: Narita, Norio
name: Penev, Kaloyan
name: Teske, Johanna K.
name: Kane, Stephen R.
name: Mann, Andrew W.
name: Addison, Brett C.
name: Tamura, Motohide
name: Horner, Jonathan
name: Barbieri, Mauro
name: Burt, Jennifer A.
name: Díaz, Matías R.
name: Crossfield, Ian J. M.
name: Dragomir, Diana
name: Drass, Holger
name: Feinstein, Adina D.
name: Zhang, Hui
name: Hart, Rhodes
name: Kielkopf, John F.
name: Jensen, Eric L. N.
name: Montet, Benjamin T.
name: Ottoni, Gaël
name: Schwarz, Richard P.
name: Rojas, Felipe
name: Nespral, David Lopez Fdez
name: Torres, Pascal
name: Mengel, Matthew W.
name: Udry, Stéphane
name: Zapata, Abner
name: Snoddy, Erin
name: Okumura, Jack
name: Ricker, George R.
name: Vanderspek, Roland K.
name: Latham, David W.
name: Winn, Joshua N.
name: Seager, Sara
name: Jenkins, Jon M.
name: Colón, Knicole D.
name: Henze, Christopher E.
name: Krishnamurthy, Akshata
name: Ting, Eric B.
name: Vezie, Michael
name: Villanueva, Steven
Publisher: name: arXiv
Year: 2020
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: 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 $0.852_{-0.062}^{+0.053} \, R_{\mathrm{J}}$ and a mass of $0.174_{-0.017}^{+0.018} \, M_{\mathrm{J}}$ and is in a 3.68 day orbit, while K2-329 b has a radius of $0.774_{-0.024}^{+0.026} \, R_{\mathrm{J}}$ and a mass of $0.260_{-0.022}^{+0.020} \, M_{\mathrm{J}}$ 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.
description: 28 pages, 9 figures, 11 tables, accepted by AJ, ancillary data also available at https://github.com/vulpicastor/toi954-data