Bibcode
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; Bonanno, Alfio; Buzasi, Derek L.; Campante, Tiago L.; Çelik Orhan, Z.; Corsaro, Enrico; Cunha, Margarida S.; Davies, Guy R.; Deheuvels, Sebastien; Grunblatt, Samuel K.; Hasanzadeh, Amir; Di Mauro, Maria Pia; García, Rafael A.; Gaulme, Patrick; Girardi, Léo; 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.; Miglio, Andrea; Monteiro, Mário J. P. F. G.; Mosser, Benoit; Noll, Anthony; Nsamba, Benard; Ong, Jia Mian Joel; Örtel, S.; Pereira, Filipe; Ranadive, Pritesh; Régulo, Clara; Rodrigues, Thaíse S.; 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 et al.
Referencia bibliográfica
The Astronomical Journal, Volume 157, Issue 6, article id. 245, 14 pp. (2019).
Fecha de publicación:
6
2019
Número de citas
86
Número de citas referidas
77
Descripción
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.
Proyectos relacionados
Sismología Solar y Estelar y Búsqueda de Exoplanetas
Los objetivos genéricos de este Proyecto son: 1) el estudio de la estructura y dinámica del interior solar, 2) la extensión de dicho estudio al caso de otras estrellas, 3) la búsqueda y caracterización de planetas extrasolares por métodos fotométricos (principalmente mediante el método de tránsitos) y espectroscópico (variaciones en la velocidad
Savita
Mathur