A Hot Saturn Orbiting an Oscillating Late Subgiant Discovered by TESS
Journal
Date Issued
2019
Author(s)
Huber, Daniel
•
Chaplin, William J.
•
Chontos, Ashley
•
Kjeldsen, Hans
•
Christensen-Dalsgaard, Jørgen
•
Bedding, Timothy R.
•
Ball, Warrick
•
Brahm, Rafael
•
Espinoza, Nestor
•
Henning, Thomas
•
Jordán, Andrés
•
Sarkis, Paula
•
Knudstrup, Emil
•
Albrecht, Simon
•
Grundahl, Frank
•
Fredslund Andersen, Mads
•
Pallé, Pere L.
•
Crossfield, Ian
•
Fulton, Benjamin
•
Howard, Andrew W.
•
Isaacson, Howard T.
•
Weiss, Lauren M.
•
Handberg, Rasmus
•
Lund, Mikkel N.
•
Serenelli, Aldo M.
•
Rørsted Mosumgaard, Jakob
•
Stokholm, Amalie
•
Bieryla, Allyson
•
Buchhave, Lars A.
•
Latham, David W.
•
Quinn, Samuel N.
•
Gaidos, Eric
•
Hirano, Teruyuki
•
Ricker, George R.
•
Vanderspek, Roland K.
•
Seager, Sara
•
Jenkins, Jon M.
•
Winn, Joshua N.
•
Antia, H. M.
•
Appourchaux, Thierry
•
Basu, Sarbani
•
Bell, Keaton J.
•
Benomar, Othman
•
•
Buzasi, Derek L.
•
Campante, Tiago L.
•
Çelik Orhan, Z.
•
•
Cunha, Margarida S.
•
Davies, Guy R.
•
Deheuvels, Sebastien
•
Grunblatt, Samuel K.
•
Hasanzadeh, Amir
•
•
García, Rafael A.
•
Gaulme, Patrick
•
•
Guzik, Joyce A.
•
Hon, Marc
•
Jiang, Chen
•
Kallinger, Thomas
•
Kawaler, Steven D.
•
Kuszlewicz, James S.
•
Lebreton, Yveline
•
Li, Tanda
•
Lucas, Miles
•
Lundkvist, Mia S.
•
Mann, Andrew W.
•
Mathis, Stéphane
•
Mathur, Savita
•
Mazumdar, Anwesh
•
Metcalfe, Travis S.
•
•
Monteiro, Mário J. P. F. G.
•
Mosser, Benoit
•
Noll, Anthony
•
Nsamba, Benard
•
Ong, Jia Mian Joel
•
Örtel, S.
•
Pereira, Filipe
•
Ranadive, Pritesh
•
Régulo, Clara
•
•
Roxburgh, Ian W.
•
Silva Aguirre, Victor
•
Smalley, Barry
•
Schofield, Mathew
•
Sousa, Sérgio G.
•
Stassun, Keivan G.
•
Stello, Dennis
•
Tayar, Jamie
•
White, Timothy R.
•
Verma, Kuldeep
•
Vrard, Mathieu
•
Yıldız, M.
•
Baker, David
•
Bazot, Michaël
•
Beichmann, Charles
•
Bergmann, Christoph
•
Bugnet, Lisa
•
Cale, Bryson
•
Carlino, Roberto
•
Cartwright, Scott M.
•
Christiansen, Jessie L.
•
Ciardi, David R.
•
Creevey, Orlagh
•
Dittmann, Jason A.
•
Do Nascimento, Jose-Dias, Jr.
•
Van Eylen, Vincent
•
Fürész, Gabor
•
Gagné, Jonathan
•
Gao, Peter
•
Gazeas, Kosmas
•
Giddens, Frank
•
Hall, Oliver J.
•
Hekker, Saskia
•
Ireland, Michael J.
•
Latouf, Natasha
•
LeBrun, Danny
•
Levine, Alan M.
•
Matzko, William
•
Natinsky, Eva
•
Page, Emma
•
Plavchan, Peter
•
Mansouri-Samani, Masoud
•
McCauliff, Sean
•
Mullally, Susan E.
•
Orenstein, Brendan
•
Garcia Soto, Aylin
•
Paegert, Martin
•
van Saders, Jennifer L.
•
Schnaible, Chloe
•
Soderblom, David R.
•
Szabó, Róbert
•
Tanner, Angelle
•
Tinney, C. G.
•
Teske, Johanna
•
Thomas, Alexandra
•
Trampedach, Regner
•
Wright, Duncan
•
Yuan, Thomas T.
•
Zohrabi, Farzaneh
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 R ☉), mass (M ⋆ = 1.212 ± 0.074 M ☉), 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” (R p = 9.17 ± 0.33 R ⊕) with an orbital period of ∼14.3 days, irradiance of F = 343 ± 24 F ⊕, and moderate mass (M p = 60.5 ± 5.7 M ⊕) and density (ρ p = 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.
Volume
157
Issue
6
Start page
245
Issn Identifier
0004-6256
Ads BibCode
2019AJ....157..245H
Rights
open.access
File(s)![Thumbnail Image]()
![Thumbnail Image]()
Loading...
Name
30434-huber_P01.pdf
Description
Miur
Size
6.39 MB
Format
Adobe PDF
Checksum (MD5)
0b16ef2cc633196cc4a269b512f452e1
Loading...
Name
huber.pdf
Description
Pdf editoriale
Size
14.83 MB
Format
Adobe PDF
Checksum (MD5)
dd0adc2579059669f88df04b3d2b5aac