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arXiv · astro-ph/0204494

Neutron Star Binaries as Central Engines of GRBs

S. Rosswog
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Abstract

We describe the results high resolution, hydrodynamic calculations of neutron star mergers. The model makes use of a new, nuclear equation of state, accounts for multi-flavour neutrino emission and solves the equations of hydrodynamics using the smoothed particle hydrodynamics method with more than $10^6$ particles. The merger leaves behind a strongly differentially rotating central object of $\sim 2.5$ M$_{\odot}$ together with a distribution of hot debris material. For the most realistic case of initial neutron star spins, no sign of a collapse to a black hole can be seen. We argue that the differential rotation stabilizes the central object for $\sim 10^2$ s and leads to superstrong magnetic fields. We find the neutrino emission from the hot debris around the freshly-formed, supermassive neutron star to be substantially lower than predicted previously. Therefore the annihilation of neutrino anti-neutrino pairs will have difficulties to power very energetic bursts ($\gg 10^{49}$ erg).

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S. Rosswog. 2002-04-29. Neutron Star Binaries as Central Engines of GRBs. https://doi.org/10.1063/1.1579343

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