# Stellar population synthesis based modelling of the Milky Way using asteroseismology of dwarfs and subgiants from Kepler

## TL;DR

This study revisits asteroseismic data of Kepler dwarf and subgiant stars to understand discrepancies in stellar mass distributions, revealing model inaccuracies and the impact of scaling relation corrections on the results.

## Contribution

It provides a detailed analysis of Milky Way models using asteroseismology, highlighting the effects of model inaccuracies and scaling relation corrections on stellar mass distribution predictions.

## Key findings

- TRILEGAL predicts more massive and bluer stars than Galaxia.
- Both models fail to accurately reproduce the observed  space distribution.
- Applying corrections to  scaling relations narrows the mass distribution without shifting the mean.

## Abstract

Early attempts to apply asteroseismology to study the Galaxy have already shown unexpected discrepancies for the mass distribution of stars between the Galactic models and the data; a result that is still unexplained. Here, we revisit the analysis of the asteroseismic sample of dwarf and subgiant stars observed by Kepler and investigate in detail the possible causes for the reported discrepancy. We investigate two models of the Milky Way based on stellar population synthesis, Galaxia and TRILEGAL. In agreement with previous results, we find that TRILEGAL predicts more massive stars compared to Galaxia, and that TRILEGAL predicts too many blue stars compared to 2MASS observations. Both models fail to match the distribution of the stellar sample in $(\log g,T_{\rm eff})$ space, pointing to inaccuracies in the models and/or the assumed selection function. When corrected for this mismatch in $(\log g,T_{\rm eff})$ space, the mass distribution calculated by Galaxia is broader and the mean is shifted toward lower masses compared to that of the observed stars. This behaviour is similar to what has been reported for the Kepler red giant sample. The shift between the mass distributions is equivalent to a change of 2\% in $\nu_{\rm max}$, which is within the current uncertainty in the $\nu_{\rm max}$ scaling relation. Applying corrections to the $\Delta \nu$ scaling relation predicted by the stellar models makes the observed mass distribution significantly narrower, but there is no change to the mean.