On the Requirements for Realistic Modeling of Neutrino Transport in Simulations of Core-Collapse Supernovae

TL;DR

This study uses a detailed neutrino transport code to evaluate how various approximations affect core-collapse supernova simulations, highlighting the importance of accurate physics modeling for realistic results.

Contribution

The paper systematically assesses the impact of common approximations in supernova simulations using a versatile code, emphasizing the need for comprehensive physics inclusion.

Findings

Omission of observer corrections hampers explosion potential.

Neglecting relativistic effects alters simulation outcomes.

Simplified weak interactions reduce model accuracy.

Abstract

We have conducted a series of numerical experiments with the spherically symmetric, general relativistic, neutrino radiation hydrodynamics code Agile-BOLTZTRAN to examine the effects of several approximations used in multidimensional core-collapse supernova simulations. Our code permits us to examine the effects of these approximations quantitatively by removing, or substituting for, the pieces of supernova physics of interest. These approximations include: (1) using Newtonian versus general relativistic gravity, hydrodynamics, and transport; (2) using a reduced set of weak interactions, including the omission of non-isoenergetic neutrino scattering, versus the current state-of-the-art; and (3) omitting the velocity-dependent terms, or observer corrections, from the neutrino Boltzmann kinetic equation. We demonstrate that each of these changes has noticeable effects on the outcomes of our simulations. Of these, we find that the omission of observer corrections is particularly detrimental to the potential for neutrino-driven explosions and exhibits a failure to conserve lepton number. Finally, we discuss the impact of these results on our understanding of current, and the requirements for future, multidimensional models.