Dynamical Evolution of Substructured Star Clusters at 3 kpc from the Galactic Center

We investigate the evolution of initial fractal clusters at 3 kpc from the Galactic Center (GC) of the Milky Way and show how red supergiant clusters (RSGCs)-like objects, which are considered to be the result of active star formation in the Scutum complex, can form by 16 Myr. We find that initial tidal filling and tidal over-filling fractals are shredded by the tidal force, but some substructures can survive as individual subclusters, especially when the initial virial ratio is ≤0.5. These surviving subclusters are weakly mass segregated and show a top-heavy mass function. This implies the possibility that a single substructured star cluster can evolve into multiple ‘star clusters’.