Asteroseismic modelling of solar-type stars: A deeper look at the treatment of initial helium abundance

Abstract

Detailed understanding of stellar physics is essential towards a robust determination of stellar properties (e.g. radius, mass, and age). Among the vital input physics used in the modelling of solar-type stars which remain poorly constrained, is the initial helium abundance. To this end, when constructing stellar model grids, the initial helium abundance is estimated either (i) by using the semi-empirical helium-to-heavy element enrichment ratio, ($\Delta Y/\Delta Z$), anchored to the standard Big Bang Nucleosynthesis value or (ii) by setting the initial helium abundance as a free variable. Adopting 35 low-mass, solar-type stars with multi-year Kepler photometry from the asteroseismic "LEGACY" sample, we explore the systematic uncertainties on the inferred stellar parameters (i.e., radius, mass, and age) arising from the treatment of the initial helium abundance in stellar model grids . The stellar masses and radii derived from grids with free initial helium abundance are lower compared to those from grids based on a fixed $\Delta Y/\Delta Z$ ratio. We find the systematic uncertainties on mean density, radius, mass, and age arising from grids which employ a fixed value of $\Delta Y/\Delta Z$ and those with free initial helium abundance to be $\sim$ 0.9%, $\sim$ 2%, $\sim$ 5% and $\sim$ 29%, respectively. We report that the systematic uncertainties on the inferred masses and radii arising from the treatment of initial helium abundance in stellar grids lie within the expected accuracy limits of ESA's PLATO, although this is not the case for the age.

12 pages, 10 figures, and 6 tables. Accepted for publication in MNRAS

References in corpus (23)

• The APOKASC Catalog: An Asteroseismic and Spectroscopic Joint Survey of Targets in the Kepler Fields
• Correcting stellar oscillation frequencies for near-surface effects
• Standing on the shoulders of Dwarfs: the Kepler asteroseismic LEGACY sample II - radii, masses, and ages
• Standing on the shoulders of Dwarfs: the $Kepler$ asteroseismic LEGACY sample I - oscillation mode parameters
• A new correction of stellar oscillation frequencies for near-surface effects
• YREC: The Yale Rotating Stellar Evolution Code
• Asteroseismology for "à la carte" stellar age-dating and weighing: Age and mass of the CoRoT exoplanet host HD 52265
• A precise asteroseismic age and radius for the evolved Sun-like star KIC 11026764
• An asteroseismic signature of helium ionization
• Stroemgren survey for Asteroseismology and Galactic Archaeology: let the SAGA begin
• Determining stellar parameters of asteroseismic targets: going beyond the use of scaling relations
• The Helium abundance and Delta Y / Delta Z in Lower Main Sequence stars
• AIMS - A new tool for stellar parameter determinations using asteroseismic constraints
• The Chemical Evolution of Helium
• Asteroseismic estimate of helium abundance of a solar analog binary system
• Seismic measurement of the locations of the base of convection zone and helium ionization zone for stars in the {\it Kepler} seismic LEGACY sample
• Prospects for asteroseismic inference on the envelope helium abundance in red giant stars
• Helium signature in red giant oscillation patterns observed by Kepler
• Asteroseismology of 36 Kepler subgiants -- II: Determining ages from detailed modelling
• Convective boundary mixing in low- and intermediate-mass stars I. Core properties from pressure-mode asteroseismology
• TESS Asteroseismic Analysis of the Known Exoplanet Host Star HD 222076
• On using dipolar modes to constrain the helium glitch in red-giant stars
• On the nature of the core of $\alpha$ Centauri A: the impact of the metallicity mixture

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