Mixed-mode ensemble asteroseismology of low-luminosity Kepler red giants

• Verfasst von: Kuszlewicz, James S. [VerfasserIn]
• Verfasst von: Hon, Marc [VerfasserIn]
• Verfasst von: Huber, Daniel [VerfasserIn]
• Titel: Mixed-mode ensemble asteroseismology of low-luminosity Kepler red giants
• Verf.angabe: James S. Kuszlewicz, Marc Hon, Daniel Huber
• E-Jahr: 2023
• Jahr: 2023 September 10
• Umfang: 19 S.
• Fussnoten: Gesehen am 06.12.2024
• Titel Quelle: Enthalten in: The astrophysical journal / 1
• Ort Quelle: London : Institute of Physics Publ., 1995
• Jahr Quelle: 2023
• Band/Heft Quelle: 954(2023), 2, Artikel-ID 152, Seite 1-19
• ISSN Quelle: 1538-4357
• DOI: doi:10.3847/1538-4357/ace598
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1872107451

Abstract

We present measurements of the dipole mode asymptotic period spacing (ΔΠ1), the coupling factor between the p- and g-modes (q), the g-mode phase offset (ϵ g ), and the mixed-mode frequency rotational splitting (δ ν rot) for 1074 low-luminosity red giants from the Kepler mission. Using oscillation mode frequencies extracted from each star, we apply Bayesian optimization to estimate ΔΠ1 from the power spectrum of the stretched-period spectrum and to perform the subsequent forward modeling of the mixed-mode frequencies. With our measurements, we show that the mode coupling factor q shows significant anticorrelation with both the stellar mass and metallicity, and can reveal highly metal-poor stars. We present the evolution of ϵ g up the lower giant branch up to before the luminosity bump, and find no significant trends in ϵ g or δ ν rot with the stellar mass and metallicity in our sample. Additionally, we identify six new red giants showing anomalous distortions in their g-mode pattern. Our data products, code, and results are provided in a public repository.