Stellar diameters and temperatures. VI. High angular resolution measurements of the transiting exoplanet host stars HD 189733 and HD 209458 and implications for models of cool dwarfs
Article
Article Title | Stellar diameters and temperatures. VI. High angular resolution measurements of the transiting exoplanet host stars HD 189733 and HD 209458 and implications for models of cool dwarfs |
---|---|
ERA Journal ID | 1074 |
Article Category | Article |
Authors | Boyajian, Tabetha (Author), von Braun, Kaspar (Author), Feiden, Gregory A. (Author), Huber, Daniel (Author), Basu, Sarbani (Author), Demarque, Pierre (Author), Fischer, Debra A. (Author), Schaefer, Gail (Author), Mann, Andrew W. (Author), White, Timothy R. (Author), Maestro, Vicente (Author), Brewer, John (Author), Lamell, C. Brooke (Author), Spada, Federico (Author), Lopez-Morales, Mercedes (Author), Ireland, Michael (Author), Farrington, Chris (Author), van Belle, Gerard T. (Author), Kane, Stephen R. (Author), Jones, Jeremy (Author), ten Brummelaar, Theo A. (Author), Ciardi, David R. (Author), McAlister, Harold A. (Author), Ridgway, Stephen (Author), Goldfinger, P. J. (Author), Turner, Nils H. (Author) and Sturmann, Laszlo (Author) |
Journal Title | Monthly Notices of the Royal Astronomical Society |
Journal Citation | 447 (1), pp. 846-857 |
Number of Pages | 12 |
Year | 2015 |
Publisher | Oxford University Press |
Place of Publication | United Kingdom |
ISSN | 0035-8711 |
1365-2966 | |
Digital Object Identifier (DOI) | https://doi.org/10.1093/mnras/stu2502 |
Web Address (URL) | https://academic.oup.com/mnras/article/447/1/846/1753469 |
Abstract | We present direct radii measurements of the well-known transiting exoplanet host stars HD 189733 and HD 209458 using the CHARA Array interferometer. We find the limbdarkened angular diameters to be θLD = 0.3848 ± 0.0055 and 0.2254 ± 0.0072 mas for HD 189733 and HD 209458, respectively. HD 189733 and HD 209458 are currently the only two transiting exoplanet systems where detection of the respective planetary companion's orbital motion from high-resolution spectroscopy has revealed absolute masses for both star and planet. We use our new measurements together with the orbital information from radial velocity and photometric time series data, Hipparcos distances, and newly measured bolometric fluxes to determine the stellar effective temperatures (Teff = 4875 ± 43, 6092 ± 103 K), stellar linear radii (R* =0.805±0.016, 1.203±0.061 R), mean stellar densities (ρ* =1.62±0.11, 0.58 ± 0.14 ρ), planetary radii (Rp = 1.216 ± 0.024, 1.451 ± 0.074 RJup), and mean planetary densities (ρp = 0.605 ± 0.029, 0.196 ± 0.033 ρJup) for HD 189733b and HD 209458b, respectively. The stellar parameters for HD 209458, an F9 dwarf, are consistent with indirect estimates derived from spectroscopic and evolutionary modelling. However, we find that models are unable to reproduce the observational results for the K2 dwarf, HD 189733. We show that, for stellar evolutionary models to match the observed stellar properties of HD 189733, adjustments lowering the solar-calibrated mixing-length parameter to αMLT =1.34 need to be employed. |
Keywords | Infrared stars;HD 189733; HD 209458; Stars: late-type; Techniques: interferometric; |
ANZSRC Field of Research 2020 | 510109. Stellar astronomy and planetary systems |
519999. Other physical sciences not elsewhere classified | |
Public Notes | This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2015 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved. |
Byline Affiliations | Yale University, United States |
Lowell Observatory, United States | |
Uppsala University, Sweden | |
National Aeronautics and Space Administration (NASA), United States | |
Massey University, New Zealand | |
Mount Wilson Observatory, United States | |
University of Texas, United States | |
Georg August University of Gottingen, Germany | |
University of Sydney | |
Leibniz Institute for Astrophysics, Germany | |
Center for Astrophysics Harvard and Smithsonian, United States | |
Australian National University | |
San Francisco State University, United States | |
Georgia State University, United States | |
National Optical Astronomy Observatory, United States | |
Institution of Origin | University of Southern Queensland |
https://research.usq.edu.au/item/q4307/stellar-diameters-and-temperatures-vi-high-angular-resolution-measurements-of-the-transiting-exoplanet-host-stars-hd-189733-and-hd-209458-and-implications-for-models-of-cool-dwarfs
Download files
1219
total views106
total downloads4
views this month1
downloads this month