Code for Astrophysics

Software for simulating and post-processing SNe Ia

Computation of nucleosynthetic yield for SN Ia consists of 3 steps, which involve various software.

The first step is the simulation itself. This is performed in the Flash Astrophysical Hydrodynamics Software along with several additions. The additions are available here:

The reaction-diffusion formalism for thickened flames in the "Flame" Unit is the same as that distributed with more recent releases of the mainline Flash software, although it is located in a different place in the source tree. This will be reconciled in future versions.

The second step is construction of the histories of tracer particles from the files saved by Flash. This is performed with particle tools:

The third step is to post-process these fluid element histories using the Torch nuclear reaction network available below. The scripts used to perform this post-processing are available here:

My version of the Torch nuclear network code

Torch is Frank Timmes' general nuclear network code, and is available from his code website. My version has been modified in several ways to be used to compute nucleosynthetic yields from multidimensional simulations of thermonuclear supernovae. Modifications include improvement of the jacobian terms used for computing detonations, addition of a specified-pressure-history self-heating mode, and addition of a weak rate table including rates from Langanke & Martinez-Pinedo (table compiled by Ed Brown).

You can obtain the code with either of the following:

Note that the version of mainline torch that I started from was from a decent while ago.

Surface Helium Detonation on a WD in Plane Parallel Uniform Gravity

A Simulation Unit for Flash 4

do git clone

or here is the git repository tarballed

Also requires this patch that allows calling of EOS by specifying abar and zbar instead of species.

This is used in Moore, Townsley, and Bildsten 2013, ApJ, submitted.

Helium Strip Detonation

A Simulation Unit for Flash 4

do git clone

or here is the git repository tarballed

This is used in Moore, Townsley, and Bildsten 2013, ApJ, submitted.

Type Ia Supernova FLASH Simulation Unit


From Readme :

Dean M. Townsley 2009, Additional testing and input by: Aaron P. Jackson, Alan C. Calder

A Simulation Unit is a drop-in component for the FLASH 3.0 hydrodynamics code ( which configures, initializes and implements a particular physical problem.

This is a Simulation Unit for performance of Type Ia supernova simulations with FLASH. This code is provided as a reference implementation for the randomized initial condition used by Townsley etal (2009, ApJ, in press, ArXiv:0906.4384) to construct a framework for study of SN Ia systematics based on a theoretical population of SNe Ia. The critical components for reproducability of the theoretical population are the random number generator, contained in the file sim_LCGRandomIterate.F90 and the usage of this for choosing the coefficients of the multipole initial condition. The coefficients are chosen by code in Simulation_init.F90 and their use to generate the initial flame surface appears in Simulation_initBlock.F90.

Additionally, the implementation of the refinement prescriptions described in the same paper is included in the files Grid_markRefineDerefine.F90 and gr_markRefineDerefine.F90. And an example initial WD is included in cc_7e8_linear_wd_plain.dat.

Example parameter files for both 1-d and 2-d simulations described in Townsley etal (2009) are included. Additional files are relevant to interaction with the FLASH source tree.