Description
Because they form their numerous stars so efficiently, globular clusters (GCs) have long been hypothesized to be the building blocks of young galaxies, with preliminary observations from JWST suggesting this may be the case at high redshifts. Within the Milky Way, our best tracers of the contribution of GCs to the proto-Galaxy are their most chemically peculiar stars: namely, second generation GC stars with such anomalous overabundances in nitrogen and depletions in oxygen ("high-[N/O] stars") that they can reliably be tagged as having originated in a cluster long after they have escaped. We identify associations between high-[N/O] field stars and Galactic globular clusters using their orbital integrals of motion and metallicities. These associations are compared to those between the rest of the halo and the GCs to quantify an excess association between the high-[N/O] stars and clusters, thus identifying the potential birth sites of the nitrogen-enhanced stars in the field. We find a strong degree of association with the low orbital energy, highest initial mass clusters, whereas such an association does not appear to strongly exist between the low energy clusters and high-[N/O] stars. This suggests that the most initially massive inner Galaxy clusters contributed a substantial number of the high-[N/O] stars in the halo–and confirms the in-situ origin of many of these stars. We propose that this link between these particular clusters and the nitrogen-enhanced halo stars exists because only in the inner Galaxy can the most massive clusters--which form the most second generation, high-[N/O] stars—be significantly stripped.
