Basic Geant4 scintillation example

Shows working scintillation and optical propagation, compatible with at least Geant4v11.02

Scintillator is CeBr3. Properties are written in header files and then assigned in src/Materials.cc.

You can configure some settings in DetectorConstruction.cc, and enable or disable scintillation in main.cc.

How to run the code

1. Install Geant4 using the getting started guide from CERN.
2. Open a terminal and run mkdir build && cd build && cmake .. && make
3. Run the output executable.
4. Run a macro, for example /control/execute macros/gps_beam_center.mac and then /run/beamOn 1. You should get a response like in the photo below.

File output

files output into folder of format 'run#-date-time'

output files per run:

• scint-phots-out.tab -> number of scintillated photons per event
• si-out.tab -> number of detected scintillated photons per event
• cryst-out.tab -> energy deposit for event (sum over each hit) or individual hit energies (configurable in Analysis.hh)
• spec-in.tab -> input energy spectrum

the files are saved by class Analysis.

Things that can be configured

configurable in DetectorConstruction.hh and DetectorConstruction.cc:

• air gap between crystal, teflon, aluminum (it's really big at the moment)
• build teflon or not
• build aluminum or not the aluminum is red and the teflon is green just for clarity.

configurable in Analysis.cc

• save silicon detector hit positions (saveSiPositions)
• save positions of hits inside of crystal (saveCrystPos)
• save each hit energy, not just the sum for an event (saveEachHitEnergy)

Important notes

if you set the RINDEX for aluminum and give it a G4OpticalSkinSurface you can get weird crashes like the one in failed-aluminum.txt

you can test just optical photons using macros/optical_diagnose.mac and then beamOn. you can test scintillation using the G4GeneralParticleSource like in macros/gps_beam_center.mac and then beamOn.