The origin of multiple stellar populations (MSPs) in globular clusters (GCs) remains a mystery. Various scenarios have been proposed, suggesting that the enriched populations form through pollution from the first generation of stars. Through numerical N-body models, we have discovered a strong connection between stellar mergers during the formation stage of GCs and the formation of these polluters, indicating that stellar dynamics play a crucial role in MSP formation. The occurrence of stellar mergers is particularly enhanced in binary-rich clusters, where stars formed from gas polluted by merger-driven ejections or winds manifest as MSPs. Our findings underscore the significance of stellar mergers as a process that links MSP formation to star cluster dynamics, enabling multiple MSP formation channels to coexist naturally. The scenario examined here, alongside a potential top-heavy initial mass function, offers a compelling explanation for the high mass fraction of MSPs (addressing the mass budget problem) and the absence of MSPs in young and low-mass star clusters.
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