An Open-Source Neutrino Radiation Hydrodynamics Code for Core-Collapse Supernovae

Evan O'Connor
The Astrophysical Journal: Supplement, 219, 24 (2015)


We present an open-source update to the spherically-symmetric, general-relativistic hydrodynamics, core-collapse supernova code GR1D (O'Connor & Ott, 2010, CQG, 27, 114103). The source code is available at We extend its capabilities to include a fully general relativistic treatment of neutrino transport based on the moment formalisms of Shibata et al., 2011, PTP, 125, 1255 and Cardall et al., 2013, PRD, 87 103004. We pay special attention to implementing and testing numerical methods and approximations that lessen the computational demand of the transport scheme by removing the need to invert large matrices. This is especially important for the implementation and development of moment-like transport methods in two and three dimensions. A critical component of neutrino transport calculations are the neutrino-matter interaction coefficients that describe the production, absorption, scattering, and annihilation of neutrinos. In this article we also describe our open-source, neutrino interaction library NuLib (available at We believe that an open-source approach to describing these interactions is one of the major steps needed to progress towards robust models of core-collapse supernovae and robust predictions of the neutrino signal. We show, via comparisons to full Boltzmann neutrino transport simulations of core collapse, that our neutrino transport code performs remarkably well. Furthermore, we show that the methods and approximations we employ to increase efficiency do not decrease the fidelity of our results. We also test the ability of our general relativistic transport code to model failed core-collapse supernovae by evolving a 40 solar mass zero-age main sequence mass progenitor to the onset of protoneutron star collapse to a black hole.

Simulation Code

Our simulation code is available at as tagged git repository (tag 'GR1Dv2'). We use the equation of state tables from, particularly the LS180 and LS220. We generate the neutrino interaction rates with NuLib (available at and have tagged a version also called 'GR1Dv2'. Please direct comments and questions to Evan O'Connor (evanoconnor 'at'

NuLib tables

Here are the NuLib tables used in the article, they are all reproducible from the GR1Dv2 tagged version of NuLib but also provided here.

For our comparison simulation with Liebendoerfer et al. (2005), the following table is needed:

For Figure 7 the following tables are needed:
A NuLib table with our heavy-lepton neutrino production/annihilation approximation using only electron-positron annihilation as a interaction: NuLib_LS180_noweak_nonnbrem_rho82_temp65_ye51_ng18_ns3_Itemp65_Ieta61_version1.0_20141111.h5
A NuLib table with electron-position pair produciton / neutrino-antineutrino annihilation kernels: NuLib_LS180_noweak_epkernels_rho82_temp65_ye51_ng18_ns3_Itemp65_Ieta61_version1.0_20141111.h5

For the black hole formation run the following table is needed:

Simulation Results

All of the results presented in this article are reproducible with the 'GR1Dv2' tagged releases of our codes. A tarball of the parameter files necessary to do this is linked here, they are also available in the source code repository in the sample_parameter_files directory. The collection of data we used (and any scripts needed for data manipulation) for the figures and discussion in the article is available here. The data from Liebendoerfer et al. (2005) is available from their publisher here. We do not publish here the initial progenitor data from Woosley & Weaver (1995) or Woosley & Heger (2007).