[Y/Mg] as a Stellar Chronometer: Combining Asteroseismic and Chemical Data

The determination of stellar ages remains one of the greatest challenges in astrophysics, as age cannot be directly measured. Advances over the last decade highlight a great potential of chemical clocks, particularly abundance ratios involving s-process and α-elements to estimate stellar ages with improved precision. For a sample of 205 stars observed with the high-resolution spectrograph and 1.65 m telescope at the Molėtai Astronomical Observatory in Lithuania, we determined Y and Mg abundances and derived new asteroseismic ages from TESS observations. Our results reveal the dependence of the [Y/Mg]–age relationship on the Galactic birthplaces of thin-disc stars, while confirming previous results on negligible correlations for thick-disc stars. This study highlights the importance of integrating chemical compositions, asteroseismic data, and precise astrometric measurements from Gaia to refine the applicability of chemical clocks and enhance our understanding of Galactic chemical evolution.