Physical properties of eclipsing binaries containing intermediate-mass pulsators or low-mass stars

Jennings, Zachary Paul Stephen

Abstract

Precise stellar parameter measurements are crucial for improving our theoretical understanding of stellar structure. They help quantify model errors and uncertainties and provide vital constraints for interpreting observed phenomena, such as radius inflation in low-mass stars. To advance stellar theory, particularly for main-sequence intermediate-mass stars, we need to move beyond simplifications related to complex processes like mixing, convection, and magnetism.
Spectroscopically double-lined eclipsing binaries offer precise measurements of conventional properties like mass and radius using geometry-based methods, achieving model-independent precisions often better than 1%. Asteroseismology constrains stellar interiors, reducing model flexibility and enhancing theory-to-observation comparisons. Simultaneously, binarity narrows parameter space and resolves model ambiguities for asteroseismology. These synergies make double-lined eclipsing binary systems with pulsating components invaluable for advancing stellar theory, while also enabling investigations of tidal effects on pulsations.
This work presents the analysis of two doubled lined detached eclipsing binary systems, KIC 9851944 and KIC 4851217, each of which consists of a δ Scuti pulsator and another intermediate mass star. The masses and radii of the components in each EB are measured to precisions better than 1% on average. We report the detection of tidally perturbed pulsations in KIC 9851944 and tidally tilted pulsations, as well as a tertiary component in KIC 4851217. Pulsation mode identification would make these systems well-equipped for advancing intermediate-mass stellar theory with asteroseismology.
For low-mass stellar theory, observational constraints are limited due to the rarity of eclipsing systems featuring two spectroscopically detectable low-mass stars. Increasing instances of M dwarfs transiting brighter F/G dwarfs offer indirect measurements and calibration opportunities. By utilising TESS data and radial velocity measurements, we also improve the characterization of 12 such binaries in this work, in addition to two where we present the first measurements of the M dwarf’s properties.

Citation

Jennings, Z. P. S. (2024). Physical properties of eclipsing binaries containing intermediate-mass pulsators or low-mass stars. (Thesis). Keele University. Retrieved from https://keele-repository.worktribe.com/output/775631

• Thesis Type: Thesis
• Deposit Date: Mar 15, 2024
• Publicly Available Date: Mar 15, 2024
• Public URL: https://keele-repository.worktribe.com/output/775631
• Award Date: 2024-03