Speaker
Description
It is well established that Globular Clusters (GCs) are formed by multiple populations (MPs) with different light element abundances (C, N, O, Na, Mg, Al, Si, K), that are structured in well-defined patterns, such as the Na-O and Mg-Al anticorrelations. This evidence is interpreted as the result of a self-enrichment process, where a second population of stars was formed from material processed by massive stars of the first population (polluters) through the hot CNO cycle and its secondary NeNa and MgAl chains. A detailed analysis of these anticorrelations can put constraints on the models for the different proposed polluters. Mg-K anticorrelation is the most extreme manifestation of the phenomenon of MPs in GCs. Such feature was observed only in a handful of Milky Way GCs, and represents a key feature to disentangle among the different polluters proposed in literature. Here I will present the result of the very first Mg-K anticorrelation in an extragalactic GC, namely NGC 1786. Its detection confirms the universality of the MPs and puts further constraints on the theoretical models.