2021/12/03 by Meghan E. Hughes, Joel L. Pfeffer, Nate Bastian +5 · 1 citation
Physics and Astronomy · #astro-ph.GA #astro-ph.SR
paper · pdf · doi:10.1093/mnras/stab3597
Accepted to MNRAS
arxiv created 2021/12/03 · arxiv updated 2022/02/02
The mass function of globular cluster (GC) populations is a fundamental observable that encodes the physical conditions under which these massive stellar clusters formed and evolved. The high-mass end of star cluster mass functions are commonly described using a Schechter function, with an exponential truncation mass Mc,*. For the GC mass functions in the Virgo galaxy cluster, this truncation mass increases with galaxy mass (M*). In this paper we fit Schechter mass functions to the GCs in the most massive galaxy group (M200 = 5.14 × 1013 M\odot) in the E-MOSAICS simulations. The fiducial cluster formation model in E-MOSAICS reproduces the observed trend of Mc,* with M* for the Virgo cluster. We therefore examine the origin of the relation by fitting Mc,* as a function of galaxy mass, with and without accounting for mass loss by two-body relaxation, tidal shocks and/or dynamical friction. In the absence of these mass-loss mechanisms, the Mc,*-M* relation is flat above M_* > 1010 M\odot. It is therefore the disruption of high-mass GCs in galaxies with M*∼ 1010 M\odot that lowers the Mc,* in these galaxies. High-mass GCs are able to survive in more massive galaxies, since there are more mergers to facilitate their redistribution to less-dense environments. The Mc,*-M_* relation is therefore a consequence of both the formation conditions of massive star clusters and their environmentally-dependent disruption mechanisms.