Implementation of Msc model for proton in EmStandard_opt4

[Guillaume_Houyoux]

_Geant4 Version:_11.0.0
_Operating System:_Linux
_Compiler/Version:_gcc/11.4.0
_CMake Version:_cmake/3.22.1

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Hi Geant4 community,

I wanted to have a closer look to the implementation of the multiple scattering as modeled for protons in EmStandard_Opt4. In the documentation, it is written that the Wentzel IV model is used, but I am not able to find exactly where it is given in /source/physics_lists/constructors/electromagnetic/src/G4EmStandardPhysics_option4.cc

Can anyone help me ?

Cheers,

Guillaume.

[Alex2671]

particle = G4Positron::Positron();
msc1 = new G4GoudsmitSaundersonMscModel();
msc2 = new G4WentzelVIModel();
msc1->SetHighEnergyLimit(highEnergyLimit);
msc2->SetLowEnergyLimit(highEnergyLimit);
G4EmBuilder::ConstructElectronMscProcess(msc1,msc2,particle);

you might be wonder why is positron is proton? So, it has also PenelopeIonisationIonModel() under comments “register processes”

[Guillaume_Houyoux]

Thanks a lot !

For completeness for the other users, it was indeed in the G4EmBuilder.cc file, where The WentzelVI model is the default msc model for protons.

if( isProton ) {
msc = new G4hMultipleScattering();
if(isWVI) {
msc->SetEmModel(new G4WentzelVIModel());
ss = new G4CoulombScattering();