XsecBiasingOperator.cxx

#include "SimCore/BiasOperators/XsecBiasingOperator.h"
 
#include "Framework/Exception/Exception.h"
 
namespace simcore {
 
XsecBiasingOperator::XsecBiasingOperator(
    std::string name, const framework::config::Parameters& parameters)
    : G4VBiasingOperator(name),
      the_log_{framework::logging::makeLogger(name)} {}
 
void XsecBiasingOperator::StartRun() {
  if (this->getParticleToBias().compare("gamma") == 0) {
    process_manager_ = G4Gamma::GammaDefinition()->GetProcessManager();
  } else if (this->getParticleToBias().compare("e-") == 0) {
    process_manager_ = G4Electron::ElectronDefinition()->GetProcessManager();
  } else if (this->getParticleToBias().compare("neutron") == 0) {
    process_manager_ = G4Neutron::NeutronDefinition()->GetProcessManager();
  } else if (this->getParticleToBias().compare("kaon0L") == 0) {
    process_manager_ =
        G4KaonZeroLong::KaonZeroLongDefinition()->GetProcessManager();
  } else {
    // Fallback: look up arbitrary particles via G4ParticleTable
    // This supports custom particles like A' ("A^1") and any future additions
    auto* particle = G4ParticleTable::GetParticleTable()->FindParticle(
        this->getParticleToBias());
    if (particle) {
      process_manager_ = particle->GetProcessManager();
    } else {
      EXCEPTION_RAISE("BiasSetup", "Invalid particle type '" +
                                       this->getParticleToBias() + "'.");
    }
  }
 
  ldmx_log(info) << "Biasing particles of type " << this->getParticleToBias();
 
  if (processIsBiased(this->getProcessToBias())) {
    xsec_operation_ =
        new G4BOptnChangeCrossSection("changeXsec-" + this->getProcessToBias());
  } else {
    EXCEPTION_RAISE("BiasSetup",
                    this->getProcessToBias() +
                        " is not found in list of biased processes!");
  }
}
 
bool XsecBiasingOperator::processIsBiased(std::string process) {
  // Loop over all processes and check if the given process is being
  // biased.
  const G4BiasingProcessSharedData* shared_data =
      G4BiasingProcessInterface::GetSharedData(process_manager_);
  if (shared_data) {
    for (size_t iprocess = 0;
         iprocess < (shared_data->GetPhysicsBiasingProcessInterfaces()).size();
         ++iprocess) {
      const G4BiasingProcessInterface* wrapper_process =
          (shared_data->GetPhysicsBiasingProcessInterfaces())[iprocess];
 
      if (wrapper_process->GetWrappedProcess()->GetProcessName().compareTo(
              process) == 0) {
        return true;
      }
    }
  }
  return false;
}
 
DEFINE_FACTORY(XsecBiasingOperator);
 
}  // namespace simcore