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arXiv · 2311.00031

Neutrino trapping and out-of-equilibrium effects in binary neutron star merger remnants

Pedro Luis Espino·Peter Hammond·David Radice·Sebastiano Bernuzzi·Rossella Gamba·Francesco Zappa·Luis Felipe Longo Micchi·Albino Perego
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Abstract

We study out-of-thermodynamic equilibrium effects in neutron star mergers with 3D general-relativistic neutrino-radiation large-eddy simulations. During merger, the cores of the neutron stars remain cold ($T \sim$ a few MeV) and out of thermodynamic equilibrium with trapped neutrinos originating from the hot collisional interface between the stars. However, within ${\sim}2{-}3$ milliseconds matter and neutrinos reach equilibrium everywhere in the remnant. Our results show that dissipative effects, such as bulk viscosity, if present, are only active for a short window of time after the merger.

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Pedro Luis Espino, Peter Hammond, David Radice, Sebastiano Bernuzzi, Rossella Gamba, Francesco Zappa, Luis Felipe Longo Micchi, Albino Perego. 2023-10-31. Neutrino trapping and out-of-equilibrium effects in binary neutron star merger remnants. https://arxiv.org/abs/2311.00031

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