Mergers, tidal interactions, and mass exchange in a population of disc globular clusters

Understand

We present the results of a self-consistent $N$-body simulation following the evolution of a primordial population of thick disc globular clusters (GCs).

• We study how the internal properties of such clusters evolve under the action of mutual interactions, while they orbit a Milky Way-like galaxy.
• For the first time, through analytical and numerical considerations, we find that physical encounters between disc GCs are a crucial factor that contributed to the shape of the current properties of the Galactic GC system.
• Close passages or motion on similar orbits may indeed have a significant impact on the internal structure of clusters, producing multiple gravitationally bound sub-populations through the exchange of mass and even mergers.