Study of the diagonal ridges in metallicity for different star populations

Abstract

Various surveys, like Gaia, GALAH and LAMOST, have uncovered many features of the Milky Way. In particular, they have uncovered diagonal ridges in metallicity in the (R, Vϕ) plane. In this thesis, we use a realistic N-body simulation to study these ridges. We calculate the metallicity residuals for different age populations and azimuth sectors. We find that residuals decrease with age and change with azimuth. Finally, we calculate the angular momenta of the resonances of the bar and spiral arms, and we find that there is a relation between the residuals and the resonances, but it is not conclusive