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arXiv · 2402.18303

Gray Two-moment Neutrino Transport: Comprehensive Tests and Improvements for Supernova Simulations

Haakon Andresen·Evan P. O'Connor·Oliver Eggenberger Andersen·Sean M. Couch
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Abstract

In this work we extended an energy-integrated neutrino transport method to facilitate efficient, yet precise, modeling of compact astrophysical objects. We particularly focus on core-collapse supernovae. We implemented a gray neutrino-transport framework from the literature into FLASH and performed a detailed evaluation of its accuracy in core-collapse supernova simulations. Based on comparisons with results from simulations using energy-dependent neutrino transport, we incorporated several improvements to the original scheme. Our analysis shows that our gray neutrino transport method successfully reproduces key aspects from more complex energy-dependent transport across a variety of progenitors and equations of state. We find both qualitative and reasonable quantitative agreement with multi-group M1 transport simulations. However, the gray scheme tends to slightly favor shock revival. In terms of gravitational wave and neutrino signals, there is a good alignment with the energy-dependent transport, although we find 15-30% discrepancies in the average energy and luminosity of heavy-lepton neutrinos. Simulations using the gray transport are around four times faster than those using energy-dependent transport.

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Haakon Andresen, Evan P. O'Connor, Oliver Eggenberger Andersen, Sean M. Couch. 2024-02-28. Gray Two-moment Neutrino Transport: Comprehensive Tests and Improvements for Supernova Simulations. https://doi.org/10.1051/0004-6361%2F202449776

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