Populating the Upper Black Hole Mass Gap through Stellar Collisions in Young Star Clusters

  title={Populating the Upper Black Hole Mass Gap through Stellar Collisions in Young Star Clusters},
  author={Kyle Kremer and Mario Spera and Devin Becker and Sourav Chatterjee and Ugo N. Di Carlo and Giacomo Fragione and Carl L. Rodriguez and Claire S. Ye and Frederic A. Rasio},
  journal={The Astrophysical Journal},
Theoretical modeling of massive stars predicts a gap in the black hole (BH) mass function above $\sim 40-50\,M_{\odot}$ for BHs formed through single star evolution, arising from (pulsational) pair-instability supernovae. However, in dense star clusters, dynamical channels may exist that allow construction of BHs with masses in excess of those allowed from single star evolution. The detection of BHs in this so-called "upper-mass gap" would provide strong evidence for the dynamical processing of… 
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