Radially extended metallicity profiles in nearby early-type galaxies

Stellar metallicity gradients in the outer regions of galaxies are a critical tool for disentangling the contributions of stars formed locally and stars accreted from external systems. In my thesis I present the first compilation of extended metallicity profiles over a wide range of galaxy for both the stellar and the globular cluster components out to previously unexplored regions. I found that more massive galaxies present shallower outer stellar and globular cluster metallicity gradients, thus confirming the importance of accretion in their formation. Low mass galaxies, instead, present steeper metallicity gradients in both the components, explainable with a relative lack of mergers in their history or accretion of very low-metallicity stars in the outer regions