@article{3069055,
    title = "A Hot Saturn Orbiting an Oscillating Late Subgiant Discovered by TESS",
    author = "Huber, D. and Chaplin, W.J. and Chontos, A. and Kjeldsen, H. and Christensen-Dalsgaard, J. and Bedding, T.R. and Ball, W. and Brahm, R. and Espinoza, N. and Henning, T. and Jordán, A. and Sarkis, P. and Knudstrup, E. and Albrecht, S. and Grundahl, F. and Andersen, M.F. and Pallé, P.L. and Crossfield, I. and Fulton, B. and Howard, A.W. and Isaacson, H.T. and Weiss, L.M. and Handberg, R. and Lund, M.N. and Serenelli, A.M. and Rørsted Mosumgaard, J. and Stokholm, A. and Bieryla, A. and Buchhave, L.A. and Latham, D.W. and Quinn, S.N. and Gaidos, E. and Hirano, T. and Ricker, G.R. and Vanderspek, R.K. and Seager, S. and Jenkins, J.M. and Winn, J.N. and Antia, H.M. and Appourchaux, T. and Basu, S. and Bell, K.J. and Benomar, O. and Bonanno, A. and Buzasi, D.L. and Campante, T.L. and Çelik Orhan, Z. and Corsaro, E. and Cunha, M.S. and Davies, G.R. and Deheuvels, S. and Grunblatt, S.K. and Hasanzadeh, A. and Di Mauro, M.P. and A. García, R. and Gaulme, P. and Girardi, L. and Guzik, J.A. and Hon, M. and Jiang, C. and Kallinger, T. and Kawaler, S.D. and Kuszlewicz, J.S. and Lebreton, Y. and Li, T. and Lucas, M. and Lundkvist, M.S. and Mann, A.W. and Mathis, S. and Mathur, S. and Mazumdar, A. and Metcalfe, T.S. and Miglio, A. and F. G. Monteiro, M.J.P. and Mosser, B. and Noll, A. and Nsamba, B. and Joel Ong, J.M. and Örtel, S. and Pereira, F. and Ranadive, P. and Régulo, C. and Rodrigues, T.S. and Roxburgh, I.W. and Aguirre, V.S. and Smalley, B. and Schofield, M. and Sousa, S.G. and Stassun, K.G. and Stello, D. and Tayar, J. and White, T.R. and Verma, K. and Vrard, M. and Yildiz, M. and Baker, D. and Bazot, M. and Beichmann, C. and Bergmann, C. and Bugnet, L. and Cale, B. and Carlino, R. and Cartwright, S.M. and Christiansen, J.L. and Ciardi, D.R. and Creevey, O. and Dittmann, J.A. and Nascimento, J.-D.D. and Eylen, V.V. and Fürész, G. and Gagné, J. and Gao, P. and Gazeas, K. and Giddens, F. and Hall, O.J. and Hekker, S. and Ireland, M.J. and Latouf, N. and Lebrun, D. and Levine, A.M. and Matzko, W. and Natinsky, E. and Page, E. and Plavchan, P. and Mansouri-Samani, M. and McCauliff, S. and Mullally, S.E. and Orenstein, B. and Soto, A.G. and Paegert, M. and Van Saders, J.L. and Schnaible, C. and Soderblom, D.R. and Szabó, R. and Tanner, A. and Tinney, C.G. and Teske, J. and Thomas, A. and Trampedach, R. and Wright, D. and Yuan, T.T. and Zohrabi, F.",
    journal = "ASTRONOMICAL JOURNAL (THE)",
    year = "2019",
    volume = "157",
    number = "6",
    publisher = "INSTITUTE OF PHYSICS PUBLISHING",
    issn = "0004-6256",
    doi = "10.3847/1538-3881/ab1488",
    abstract = "We present the discovery of HD 221416 b, the first transiting planet identified by the Transiting Exoplanet Survey Satellite (TESS) for which asteroseismology of the host star is possible. HD 221416 b (HIP 116158, TOI-197) is a bright (V = 8.2 mag), spectroscopically classified subgiant that oscillates with an average frequency of about 430 μHz and displays a clear signature of mixed modes. The oscillation amplitude confirms that the redder TESS bandpass compared to Kepler has a small effect on the oscillations, supporting the expected yield of thousands of solar-like oscillators with TESS 2 minute cadence observations. Asteroseismic modeling yields a robust determination of the host star radius (R∗ = 2.943 ± 0.064 Ro), mass (M∗ = 1.212 ± 0.074 Mo), and age (4.9 ± 1.1 Gyr), and demonstrates that it has just started ascending the red-giant branch. Combining asteroseismology with transit modeling and radial-velocity observations, we show that the planet is a "hot Saturn" (Rp = 9.17 ± 0.33 R⊕) with an orbital period of ∼14.3 days, irradiance of F = 343 ± 24 F⊕, and moderate mass (Mp = 60.5 ± 5.7 M⊕) and density (ρp = 0.431 ± 0.062 g cm-3). The properties of HD 221416 b show that the host-star metallicity-planet mass correlation found in sub-Saturns (4-8 R⊕) does not extend to larger radii, indicating that planets in the transition between sub-Saturns and Jupiters follow a relatively narrow range of densities. With a density measured to ∼15%, HD 221416 b is one of the best characterized Saturn-size planets to date, augmenting the small number of known transiting planets around evolved stars and demonstrating the power of TESS to characterize exoplanets and their host stars using asteroseismology. © 2019. The American Astronomical Society. All rights reserved.."
}