# Simulations of core-collapse supernovae in spatial axisymmetry with full Boltzmann neutrino transport

## TL;DR

This paper presents the first axisymmetric supernova simulations with full Boltzmann neutrino transport, revealing detailed neutrino distributions and the impact of nuclear EOS on shock evolution.

## Contribution

It introduces a full 5D neutrino transport simulation in axisymmetry, incorporating relativistic effects and comparing different nuclear equations-of-state.

## Key findings

- Shock wave reaches ~700km in LS EOS simulation
- More vigorous turbulence in LS EOS leads to higher neutrino heating
- Non-axisymmetric neutrino angular distributions affect flux evolution

## Abstract

We present the first results of our spatially axisymmetric core-collapse supernova simulations with full Boltzmann neutrino transport, which amount to a time-dependent 5-dimensional (2 in space and 3 in momentum space) problem in fact. Special relativistic effects are fully taken into account with a two-energy-grid technique. We performed two simulations for a progenitor of 11.2M, employing different nuclear equations-of-state (EOS's): Lattimer and Swesty's EOS with the incompressibility of K = 220MeV (LS EOS) and Furusawa's EOS based on the relativistic mean field theory with the TM1 parameter set (FS EOS). In the LS EOS the shock wave reaches ~700km at 300ms after bounce and is still expanding whereas in the FS EOS it stalled at ~200km and has started to recede by the same time. This seems to be due to more vigorous turbulent motions in the former during the entire post-bounce phase, which leads to higher neutrino-heating efficiency in the neutrino-driven convection. We also look into the neutrino distributions in momentum space, which is the advantage of the Boltzmann transport over other approximate methods. We find non-axisymmetric angular distributions with respect to the local radial direction, which also generate off-diagonal components of the Eddington tensor. We find that the r {\theta}-component reaches ~10% of the dominant rr-component and, more importantly, it dictates the evolution of lateral neutrino fluxes, dominating over the {\theta}{\theta}-component, in the semi-transparent region. These data will be useful to further test and possibly improve the prescriptions used in the approximate methods.