Building CCSN Explosion Simulation with Spectral Two-Moment Neutrino Transport Using FLASH

We are developing the toolkit for high-order neutrino-radiation hydrodynamics (thornado) to simulate in an efficient and robust manner core-collapse supernova (CCSN) explosions. thornado implements spectral two-moment neutrino transport with a high-order discontinuous Galerkin method and implicit-explicit time stepping. More details of our numerical methods are presented in previous publications\footnote{Endeve et al. 2015, JCP, {287}, 151-183}\footnote{Chu et al. 2019, JCP, {389},62-93}. WeakLib\footnote{WeakLib: https://github.com/starkiller-astro/weaklib} is a microphysics library that provides input microphysics (equations of state (EoS) and neutrino opacities) by table interpolation. thornado and WeakLib have been coupled with FLASH\footnote{Fryxell et al. 2000, AJSS, 131.1, 273} as external libraries. With this enhanced FLASH code, we hope to simulate CCSN explosions in multiple dimensions with self gravity, hydrodynamics, spectral two-moment neutrino transport, the Steiner, Hempel and Fischer (SFHo)\footnote{Steiner et al. 2010, Astro. J., 722(1), p.33} EoS, and ``Bruenn~85"\footnote{Bruenn, S. W. 1985, AJSS, {58}, 771-841} neutrino opacities. Here we present select physically motivated test problems and preliminary results from gravitational collapse.