nuX is a GPU-accelerated neutrino-transport module for dynamical spacetimes, written in C++ and designed to run within the Einstein Toolkit using the CarpetX driver. CarpetX itself is built atop AMReX, a framework for block-structured adaptive mesh refinement (AMR).
nuX provides a two-moment (M1) evolution of radiation variables with analytic closures and multi-species support, interfacing with our GRMHD code AsterX.
- Two-moment (M1) neutrino transport with analytic closures (e.g., Minerbo/Levermore)
- Ray-by-ray M0 leakage transport with synchronized CarpetX subcycling
- Port of the
THC_M1code of Radice et al. 2022 - Multi-species support (typically
$ν_e$ ,$\barν_e$ ,$ν_x$ ) - Source terms for neutrino–matter coupling and stress–energy feedback (
$T^{μν}_{\rm rad}$ ) coupled with AsterX - Robust floors, masking, and diagnostics for production-quality BNS/CCSN simulations
nuX_Base— Shared radiation interface variables (rN,rE,rF,rP) used by transport and seed thornsnuX_M1— Core M1 evolution: fluxes, closures, source terms, analysis/diagnostics, stress–energy outputnuX_M0— GPU ray-by-ray M0 transport and matter couplingnuX_LeakageBase— Rate-library-independent leakage and optical depthsnuX_NuRates— Physical interaction rates & opacities viabns_nuratesnuX_WeakRates— Independent GPU-capable WeakRates implementation for transport and THC_M1 cross-validationnuX_FakeRates— Lightweight fake/constant rates for testingnuX_NuRatesToy— Toy module for testingnuX_M1_Seeds— initial data provider for various tests with M1nuX_M0_Seeds— initial data provider for various tests with M0nuX_Utils— Tensor utilities, metric helpers, math wrappers
- Instructions for downloading and building nuX with the Einstein Toolkit are available here.
- Thornlist is available here
- Simfactory files for various clusters and setup instructions can be found here.
- AsterX - GRMHD code
- CarpetX – Next-generation driver for the Einstein Toolkit
- SpacetimeX – Modules for spacetime evolution
- BNSTools – Utilities supporting BNS merger simulations