GEANT4 2016

GRAS

The Geant4 Radiation Analysis for Space (GRAS) tool is a Geant4-based application that deals with common analyses types in 3D geometry models. More information and the download of the GRAS package are found on the GRAS web page (login required). In order to use GRAS on the cluster the following steps need to be done:

1. download the GRAS-package version 3.3 (this version is working on the cluster, other versions may or may not work)
2. unpack the tar-file in your home-directory on the cluster (or another location of your choice, the following steps assume you use $HOME)
3. change into the directory gras-03-03
4. load the modules Geant/9.6 and CMake
5. execute the following commands:

mkdir build
cd build
.
.
.

After that the GRAS package is installed and ready to use. The package comes with a few examples, to test if everything work you could:

 cd $HOME/gras-03-03
 . bin/gras-env.sh         # this adds GRAS to your environment
 cd examples/magfield/example1/
 module load python
 python launch_example.py  # before you need to apply the patch below
 python plot_results.py

After this you see a number of new files, namely txt-, log-, and png-files (and some more). You need to copy these files to your local machine to view them.

In order to have the example above working you need to change a path in launch_example.py:

 os.chdir("../../../bin/Linux-g++")

should be

 os.chdir("../../../bin")

If you are using GRAS in any way for you work, please reference the official GRAS paper like so:

GRAS Paper
Official GRAS publication in IEEE Transactions on Nuclear Science:
G. Santin, V. Ivanchenko, H. Evans, P. Nieminen, E. Daly, "GRAS: A general-purpose 3-D modular simulation tool for space environment effects analysis", IEEE Trans. Nucl. Sci. 52, Issue 6, 2005, pp 2294 - 2299