TestEm6/src/PrimaryGeneratorAction.cc

0001 //
0002 // ********************************************************************
0003 // * License and Disclaimer                                           *
0004 // *                                                                  *
0005 // * The  Geant4 software  is  copyright of the Copyright Holders  of *
0006 // * the Geant4 Collaboration.  It is provided  under  the terms  and *
0007 // * conditions of the Geant4 Software License,  included in the file *
0008 // * LICENSE and available at  http://cern.ch/geant4/license .  These *
0009 // * include a list of copyright holders.                             *
0010 // *                                                                  *
0011 // * Neither the authors of this software system, nor their employing *
0012 // * institutes,nor the agencies providing financial support for this *
0013 // * work  make  any representation or  warranty, express or implied, *
0014 // * regarding  this  software system or assume any liability for its *
0015 // * use.  Please see the license in the file  LICENSE  and URL above *
0016 // * for the full disclaimer and the limitation of liability.         *
0017 // *                                                                  *
0018 // * This  code  implementation is the result of  the  scientific and *
0019 // * technical work of the GEANT4 collaboration.                      *
0020 // * By using,  copying,  modifying or  distributing the software (or *
0021 // * any work based  on the software)  you  agree  to acknowledge its *
0022 // * use  in  resulting  scientific  publications,  and indicate your *
0023 // * acceptance of all terms of the Geant4 Software license.          *
0024 // ********************************************************************
0025 //
0026 /// \file electromagnetic/TestEm6/src/PrimaryGeneratorAction.cc
0027 /// \brief Implementation of the PrimaryGeneratorAction class
0028 //
0029 //
0030 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
0031 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
0032
0033 #include "PrimaryGeneratorAction.hh"
0034
0035 #include "DetectorConstruction.hh"
0036 #include "PrimaryGeneratorMessenger.hh"
0037
0038 #include "G4Event.hh"
0039 #include "G4ParticleDefinition.hh"
0040 #include "G4ParticleGun.hh"
0041 #include "G4ParticleTable.hh"
0042 #include "G4SystemOfUnits.hh"
0043 #include "Randomize.hh"
0044
0045 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
0046
0047 PrimaryGeneratorAction::PrimaryGeneratorAction(DetectorConstruction* DC)
0048   : G4VUserPrimaryGeneratorAction(), fParticleGun(0), fDetector(DC), fRndmBeam(0), fGunMessenger(0)
0049 {
0050   fParticleGun = new G4ParticleGun(1);
0051   G4ParticleDefinition* particle = G4ParticleTable::GetParticleTable()->FindParticle("gamma");
0052   fParticleGun->SetParticleDefinition(particle);
0053   fParticleGun->SetParticleEnergy(100 * TeV);
0054   fParticleGun->SetParticleMomentumDirection(G4ThreeVector(1., 0., 0.));
0055
0056   // create a messenger for this class
0057   fGunMessenger = new PrimaryGeneratorMessenger(this);
0058 }
0059
0060 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
0061
0062 PrimaryGeneratorAction::~PrimaryGeneratorAction()
0063 {
0064   delete fParticleGun;
0065   delete fGunMessenger;
0066 }
0067
0068 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
0069
0070 void PrimaryGeneratorAction::GeneratePrimaries(G4Event* anEvent)
0071 {
0072   // this function is called at the begining of event
0073   //
0074   G4double x0 = -0.5 * (fDetector->GetSize());
0075   G4double y0 = 0. * cm, z0 = 0. * cm;
0076
0077   // randomize the beam, if requested.
0078   //
0079   if (fRndmBeam > 0.) {
0080     G4double rbeam = 0.5 * (fDetector->GetSize()) * fRndmBeam;
0081     y0 = (2 * G4UniformRand() - 1.) * rbeam;
0082     z0 = (2 * G4UniformRand() - 1.) * rbeam;
0083   }
0084   fParticleGun->SetParticlePosition(G4ThreeVector(x0, y0, z0));
0085   fParticleGun->GeneratePrimaryVertex(anEvent);
0086 }
0087
0088 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......