The Stellar Merger Scenario for Black Holes in the Pair-instability Gap

  title={The Stellar Merger Scenario for Black Holes in the Pair-instability Gap},
  author={Mathieu Renzo and Matteo Cantiello and Brian D. Metzger and Y.-F. Jiang},
  journal={arXiv: Solar and Stellar Astrophysics},
The recent detection of GW190521 stimulated ideas on how to populate the predicted black hole pair-instability mass gap. One proposed scenario is the dynamical merger of two stars below the pair instability regime forming a star with a small core and an over-sized envelope. We explore this scenario with detailed stellar evolution calculations, starting with ad-hoc initial conditions enforcing no core growth during the merger. We outline the main challenges this scenario has to overcome, in… 

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