Study of the thick disc of the Milky Way from a population synthesis model

The thick disc is a major component of the Milky Way but its epoch of formation and characteristics are still not yet well constrained. The Besançon Galaxy Model (BGM, Robin et al. 2003) is a population synthesis model based on a scenario of formation and evolution of the Galaxy, a star formation history, and a set of stellar evolution models. Thanks to Lagarde et al. (2017), new evolutionary tracks have been introduced into the Besancon Galaxy Model (STAREVOL, Lagarde et al. 2012) to provide global asteroseismic and surface chemical properties along the evolutionary stages. This updated Galaxy model will allow us to constrain the thick disc structure and history using the Markov Chain Monte Carlo fitting method (MCMC). We show preliminary results applying this MCMC method on the 2MASS photometric survey.