Force Collision Biasing

Hello colleagues,

I have been trying to apply biasing using the Force Collision method for mu+, the muPairProduction process and a carbon target of a 1 cm thickness.

In DetectorConstruction.cc, I have added:

G4BOptrForceCollision* biasingForceCollision = new G4BOptrForceCollision(“mu+”, “muPairProd”);
biasingForceCollision->AttachTo(fLBox);

And in PhysicsList.cc:

G4GenericBiasingPhysics* biasingPhysics = new G4GenericBiasingPhysics();
std::vector< G4String > processToBias;
processToBias.push_back(“muPairProd”);
biasingPhysics->Bias(“mu+”, processToBias);
physicsList->RegisterPhysics(biasingPhysics);

I have tried with several thicknesses, physics lists and cuts. While the program is compiled normally and without errors, whenever I comment the two sections above no change is observed in my output files. So, I guess that the biasing doesn’t work properly.

Could you please let me know where I am wrong?

Thank you very much in advance!

Cheers!