Countig particles at the boundary

Particles, Track, Event, Run and Biasing
1

hello,
I have to check how many electrons cross the boundary between two different material (same geometry of a calorimeter). At this point (see the code) i don’t know how to count the number of electrons with that conditions. I’m only a student and i’m trying to learn geant by myself so i miss some fundamentals and i’m sorry for this trivial question.
Thanks to all.

if (particleName==“electron” && pre_vol_name ==“Abso” && post_vol_name == “Gap”){
did_cross=true;
}

2

What you have will work.

You can test for postStepPoint->GetStepStatus() == fGeomBoundary, which means the track hit the boundary leaving the volume. That’s an integer compare, so faster than comparing strings.

You can also test the track->GetParticleDefinition() directly against G4Electron::Definition(), which is a pointer comparison instead of strings.

SteppingAction or a sensitive detector (SD) gets called on every step of every track, so if you can avoid string comparisons your job will run faster.

3

Thank you so much for the reply. But will fGeomBoundary consider the boundary between the volume and the world? What should i use to count the particles? I only need the number of electrons.