Fallback Accretion Halted by R-process Heating in Neutron Star Mergers and Gamma-Ray Bursts

  title={Fallback Accretion Halted by R-process Heating in Neutron Star Mergers and Gamma-Ray Bursts},
  author={Wataru Ishizaki and Kenta Kiuchi and Kunihito Ioka and Shinya Wanajo},
  journal={The Astrophysical Journal},
The gravitational wave event GW170817 with a macronova/kilonova shows that a merger of two neutron stars ejects matter with radioactivity including r-process nucleosynthesis. A part of the ejecta inevitably falls back to the central object, possibly powering long-lasting activities of a short gamma-ray burst (sGRB), such as extended and plateau emissions. We investigate fallback accretion with r-process heating by performing one-dimensional hydrodynamic simulations and developing a semi… 
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