DTP

Simulation with GGS

GGS Simulation of a simple detector with the silicon detectors with timing capabilities

Ingredients:

• macros/run.mac: datacard, a la Geant, to set the simulation parameters
• macros/geo.mac: datacard for the parametric geometry
• {src,include}/DetectorConstruction.{cc,hh}: definition, a la Geant, of the geometry

Typical commands:

- compilation and installation:

cd <build_path>
cmake -DCMAKE_INSTALL_PREFIX=<installation_path> <source_path> -DGGS_DIR=$GGS_SYS/
make
make install

The make install is not required and even not suggested. All the pieces are both copied in the build directory and installed: everything should work even in the build directory.

A working example can be found in useful_commands/cmake_and_compile.sh that includes also the creation of the gdml version of the geometry (see below). A reasonable approch could be to call the build dir as the source one (<git_clone_name>) but with the suffix _build, then:

cd <git_clone_name>_build
cmake -DCMAKE_INSTALL_PREFIX=${PWD/%_build}_install ${PWD/%_build} -DGGS_DIR=$GGS_SYS/
./useful_commands/cmake_and_compile.sh

and then, everytime the source code or the scripts are changed, is enough to launch a

./useful_commands/cmake_and_compile.sh

(if you change the source cmake_and_compile.sh you have to call it twice: first time is fully executed in its previous version but the cmake call changes it; second time the new versions is exectued).

- simulation:

GGSPenny -g lib/libTestGeometry.so -gd macros/geo.mac -d macros/run.mac -ro test.root

A working example can be found in useful_commands/run.sh

• visualization of the geometry and of the simulated events:

GGSLeonard -g lib/TestGeometry.gdml

GGSLeonard -g lib/TestGeometry.gdml -i test.root

Working examples can be found in useful_commands/show_geometry.sh and useful_commands/show_events.sh

- conversion from parametric geometry to GDML

GGSWolowitz -g lib/libTestGeometry.so -o lib/TestGeometry.gdml -t gdml -gd macros/geo.mac

- conversion from parametric geometry to VGM (http://ivana.home.cern.ch/ivana/VGM.html)

GGSWolowitz -g lib/libTestGeometry.so -gd macros/geo.mac -t vgm -o lib/TestGeometry.vgm.root

Analysis

• conversion from GGS output to plain ROOT file:

./exe/Digitization [output file name] <input file name 1> <input file name 2> ...

for example:

./exe/Digitization DigitOut.root GGSOutput.root

If the first and only input argument (not sure if more are passed) is a text file with a list of files they're are chained (as passing them as paramenters).

• create analysis histos:

./exe/DataAnalysis [output file name] <input file name 1> <input file name 2> ...

for example:

./exe/DataAnalysis AnaOut.root DigitOut.root

DataAnalysis output will be AnaOut.root

and

./exe/DataAnalysis_calo [output file name] <input file name 1> <input file name 2> ... [nominal energy] [min deposited energy] [max deposited energy]

for example:

./exe/DataAnalysis_calo AnaOut.root DigitOut.root 100 60 80

where DataAnalysis_calo executable analysis considers energy deposit in calorimeter. The command requires three additional arguments:

./exe/DataAnalysis_calo AnaOut.root DigitOut.root <nominal energy in GeV> <E calo min in GeV> <E calo max in GeV>

where Ecalo_min and Ecalo_max are needed to consider hit times only if in the specified energy range. The beam_energy par is just used to create the binning of the energy histos.