Physical properties of the eclipsing binary KIC 9851944 and analysis of its tidally perturbed p- and g-mode pulsations

Scientific paper - Original scientific paper

• Author: Z Jennings
• Author: J Southworth
• Author: K Pavlovski
• Author: T Van Reeth
• Author's institution: University of Zagreb; Faculty of Science; (Department of Physics); (History, Philosophy and Sociology of Science Division)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract (english)

ABSTRACT Stars that are both pulsating and eclipsing offer an important opportunity to better understand many of the physical phenomena that occur in stars, because it is possible to measure the pulsation frequencies of stars for which the masses and radii are known precisely and accurately. KIC 9851944 is a double-lined detached eclipsing binary containing two F-stars which show both pressure and gravity mode pulsations. We present an analysis of new high-resolution spectroscopy of the system and high-quality light curves from the Kepler and TESS space missions. We determine the masses and effective temperatures of the stars to 0.6 per cent precision, and their radii to 1.0 and 1.5 per cent precision. The secondary component is cooler, but larger and more massive than the primary so is more evolved; both lie inside the δ Scuti and γ Doradus instability strips. We measure a total of 133 significant pulsation frequencies in the light curve, including 14 multiplets that each contain between 3 and 19 frequencies. We find evidence for tidal perturbations to some of the p and g modes, attribute a subset of the frequencies to either the primary or secondary star, and measure a buoyancy radius and near-core rotational frequency for the primary component. KIC 9851944 is mildly metal-rich and MIST isochrones from the MESA evolutionary code agree well with the observed properties of the system for an age of 1.25 Gyr.

• Keywords (english): binaries: eclipsing – binaries: spectroscopic – stars: fundamental parameters – stars: oscillations – stars: variables: δ Scuti
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Monthly Notices of the Royal Astronomical Society
• Numbering: vol. 527, no. 2, pp. 4052-4075
• p-ISSN: 0035-8711
• e-ISSN: 1365-2966
• DOI: https://doi.org/10.1093/mnras/stad3427
• URN:NBN: urn:nbn:hr:217:751566
• Publication: 2024-01
• Document URL: https://academic.oup.com/mnras/article/527/2/4052/7379621
• Type of resource: Text
• Access conditions: Open access
• Public note: © The Author(s) 2023. Published by Oxford University Press on behalf of Royal Astronomical Society. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. Accepted 2023 November 1. Received 2023 November 1; in original form 2023 June 23.
• Created on: 2024-07-22 10:36:37