Examining the Relationship Between Convective Core Overshoot and Stellar Properties Using Asteroseismology

TL;DR

This study uses Kepler asteroseismic data to explore how core overshoot varies with stellar mass and impacts inferred stellar properties, revealing a positive correlation and significant effects on mass, radius, and age estimates.

Contribution

It provides the first detailed analysis of the mass-dependent trend of core overshoot using asteroseismology, highlighting its influence on stellar parameter inference.

Findings

Strong positive correlation between stellar mass and overshoot (slope 0.89).

Inferred stellar mass and radius can vary significantly with overshoot.

Overshoot affects age estimates due to changes in stellar parameters.

Abstract

Core overshoot is a large source of uncertainty in constructing stellar models. Whether the amount of overshoot is constant or mass dependent is not completely known, even though models sometimes assume a mass-based trend. In this work we use asteroseismic data from stars observed by \textit{Kepler} to investigate the relationship between various stellar properties and the amount of overshoot needed to properly model a given star. We find a strong positive trend between stellar mass and overshoot amount for stars between 1.1 and 1.5 $M_\odot$, with a slope of 0.89. Additionally, we investigate how inferred stellar properties change as a function of overshoot. Our model grids show that the inferred stellar mass and radius can vary by as much as 14\% and 6\% respectively, depending on the extent of overshoot. This mass spread results in a commensurate spread in the ages.