New population synthesis approach:The golden path to constrain stellar andgalactic physics

TL;DR

This paper introduces an advanced population synthesis approach using the Besançon Galaxy model to better understand stellar and galactic evolution by integrating stellar evolution, asteroseismic, and chemical data.

Contribution

It develops the BGM to include stellar evolution predictions, asteroseismic properties, and chemical abundances, enabling exploration of effects like extra-mixing in red giants and modeling of white dwarf remnants.

Findings

Inclusion of stellar evolution predictions in BGM.

Modeling of extra-mixing effects in red giants.

Potential to constrain stellar and galactic evolution.

Abstract

The cornerstone mission of the European Space Agency, Gaia, has revealed properties of 260 000 white dwarfs in the Galaxy, allowing us for the first time to constrain the evolution of white dwarfs with a large sample. Complementary surveys (CoRoT,Kepler, K2, APOGEE andGaia-ESO), will revolutionize our understanding of the formation and history of our Galaxy, providing accurate stellar masses, radii, ages, distances, and chemical properties for very large samples of stars across different Galactic stellar populations. To exploit the potential of the combination of spectroscopic, seismic and astrometric observations, the population synthesis approach is a very crucial and efficient tool. We develop the Besan\c{c}on Galaxy model (BGM, Lagarde et al.2017) for which stellar evolution predictions are included, providing the global asteroseismic properties and the surface chemical abundances along the evolution of low- and intermediate-mass stars. For the first time, the BGM can explore the effects of an extra-mixing occurring in red-giant stars (Lagarde et al.2019), changing their stellar properties. The nextstep is to model a consistent treatment of giant stars and their remnants (e.g., white dwarfs).This kind of improvement would help us to constrain stellar and Galactic evolutions.