Star-crossed Clusters: Asteroseismic Ages for Individual Stars are in Tension with the Ages of their Host Clusters

TL;DR

Asteroseismic ages for stars in well-studied clusters show high variance and conflict with traditional isochrone-based ages, indicating potential unaccounted factors affecting age estimates.

Contribution

This study highlights discrepancies between asteroseismic and isochrone ages in clusters, suggesting the need for new corrections or understanding of stellar processes.

Findings

Significant variance in asteroseismic ages within clusters

Discrepancies exceed known age uncertainties

Potential influence of binary processes or unaccounted corrections

Abstract

A meta-analysis of seismic ages determined for individual stars in the well-studied open and globular clusters NGC 6819, NGC 6791, M67, M4, M19, M80, and M9 reveals both high variance across measurements and significant discrepancy with independent, isochrone-based age determinations for the clusters in which these stars reside. The scatter among asteroseismic ages for individual stars in any one of these clusters far surpasses both the absolute age uncertainty computed for reference cluster M92 (5.4\%) and the model-to-model systematic uncertainties in isochrones (roughly 10\%). This suggests that either binary processes are significantly altering the masses of stars in these clusters, or some additional corrections, perhaps as a function of mass, metallicity, or surface gravity, are required to bring the asteroseismic age scale into concordance with ages inferred from isochrone or similar model fitting.