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  • General-relativistic Radiation Transport Scheme in Gmunu. II. Implementation of Novel Microphysical Library for Neutrino Radiation—Weakhub
Title: General-relativistic Radiation Transport Scheme in Gmunu. II. Implementation of Novel Microphysical Library for Neutrino Radiation—Weakhub
Abstract We introduceWeakhub, a novel neutrino microphysics library that provides opacities and kernels beyond conventional interactions used in the literature. This library includes neutrino–matter, neutrino–neutrino interactions and plasma process, along with corresponding weak and strong corrections. A full kinematics approach is adopted for the calculations ofβ-processes, incorporating various weak corrections and medium modifications due to the nuclear equation of state. Calculations of plasma processes, electron neutrino–antineutrino annihilation, and nuclear de-excitation are also included. We also present the detailed derivations of weak interactions and the coupling to the two-moment based general-relativistic multigroup radiation transport in the general-relativisticmultigridnumerical (Gmunu) code. We compare the neutrino opacity spectra for all interactions and estimate their contributions at hydrodynamical points in core-collapse supernovae and binary neutron star (BNS) postmerger remnants, and predict the effects of improved opacities in comparison to conventional ones for a BNS postmerger at a specific hydrodynamical point. We test the implementation of the conventional set of interactions by comparing it to an open-source neutrino libraryNuLibin a core-collapse supernova simulation. We demonstrate good agreement with discrepancies of less than ∼10% in luminosity for all neutrino species, while also highlighting the reasons contributing to the differences. To compare the advanced interactions to the conventional set in core-collapse supernova modeling, we perform simulations to analyze their impacts on neutrino signatures, hydrodynamical behaviors, and shock dynamics, showing significant deviations.  more » « less
Award ID(s):
2020275
PAR ID:
10509464
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
IOP
Date Published:
Journal Name:
The Astrophysical Journal Supplement Series
Volume:
272
Issue:
1
ISSN:
0067-0049
Page Range / eLocation ID:
9
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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