Proton energy deposit (secondaries) by bremsstrahlung

I was checking energy deposit (dE/dx vs Kinetic Energy) of proton by changing physics process, and saw different energy deposit.

The energy deposit with FTFP_BERT or QGSP_BERT is very different from the one with G4EmStandardPhysics only. Why?


how you measure dEdx?


Note that the total energy deposited by a track need not be only dE/dx.

When I look “TestEm18”, there is a code (as follows).

I just inject a single proton, and I take deposited energy from secondaries particles using below code. Here, I assume all particles are derived from radiation loss (bremsstrahlung)

StackingAction::ClassifyNewTrack(const G4Track* track)
   if (charged) {
   } else {

Note that the total energy deposited by a track need not be only dE/dx.

This means …

In the left, I’m looking “simple” radiation/brems loss (by looking all secondaries which are generated by the radiation/brems loss) This is because physics process I register is only “EM”_standard.

In the right, I’m including “other” physics effect (not only radiation loss) which relates to a proton. This is because I register other physics processes (not only “EM”). To see whether it is derived from the radiation loss, I have to follow each secondaries.

Am I correct?

Yes, of course ! TestEm18 assumes that there are only Em processes registered.

Dear all
Thanks for the comments.