Determine whether discrepant component ages are genuine

Determine whether the seven M51 eclipsing-binary systems identified as formally discrepant in component age are genuinely age-discrepant, rather than appearing discrepant because the inferred ages depend strongly on the adopted stellar-evolution models, using independent spectroscopic and dynamical-mass constraints where necessary.

Background

The paper fits temperatures, radii, and surface gravities for both components of 136 M51 eclipsing-binary candidates and compares them with solar-metallicity MIST stellar-evolution tracks to infer apparent component ages. Most systems are consistent with coevality, but seven systems are discrepant at the formal 95% level.

The authors caution that these apparent age differences may result from model dependence or binary-interaction processes such as mass transfer, tidal distortion, rotational mixing, contact evolution, or mergers. They state that independent spectroscopy and dynamical masses are needed to measure surface gravities more precisely and establish whether the discrepancies are statistically real.