dc.contributor.author | Huber, Daniel | |
dc.contributor.author | Crossfield, Ian | |
dc.date.accessioned | 2020-12-23T19:47:01Z | |
dc.date.available | 2020-12-23T19:47:01Z | |
dc.date.issued | 2019-05-30 | |
dc.identifier.citation | Daniel Huber et al 2019 AJ 157 245 | en_US |
dc.identifier.uri | http://hdl.handle.net/1808/31003 | |
dc.description.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 (Rsstarf = 2.943 ± 0.064 R⊙), mass (Msstarf = 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" (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. | en_US |
dc.publisher | IOP Publishing | en_US |
dc.rights | © 2019. The American Astronomical Society. All rights reserved. | en_US |
dc.subject | Asteroseismology | en_US |
dc.subject | Techniques: photometric | en_US |
dc.subject | Planets and satellites: individual | en_US |
dc.subject | (HD 221416 b) | en_US |
dc.subject | Stars: fundamental parameters | en_US |
dc.subject | Planets and satellites: fundamental parameters | en_US |
dc.title | A Hot Saturn Orbiting an Oscillating Late Subgiant Discovered by TESS | en_US |
dc.type | Article | en_US |
kusw.kuauthor | Crossfield, Ian | |
kusw.kudepartment | Physics and Astronomy | en_US |
dc.identifier.doi | 10.3847/1538-3881/ab1488 | en_US |
dc.identifier.orcid | https://orcid.org/0000-0001-8832-4488 | en_US |
kusw.oaversion | Scholarly/refereed, publisher version | en_US |
kusw.oapolicy | This item meets KU Open Access policy criteria. | en_US |
dc.rights.accessrights | openAccess | en_US |