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25 //
26 //
27 /// \file B1/src/PrimaryGeneratorAction.cc
28 /// \brief Implementation of the B1::PrimaryGeneratorAction class
29
30 #include "PrimaryGeneratorAction.hh"
31
32 #include "G4Box.hh"
33 #include "G4LogicalVolume.hh"
34 #include "G4LogicalVolumeStore.hh"
35 #include "G4ParticleGun.hh"
36 #include "G4ParticleTable.hh"
37 #include "G4SystemOfUnits.hh"
38 #include "Randomize.hh"
39
40 namespace B1
41 {
42
43 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
44
45 PrimaryGeneratorAction::PrimaryGeneratorAction()
46 {
47 G4int n_particle = 1;
48 fParticleGun = new G4ParticleGun(n_particle);
49
50 // default particle kinematic
51 G4ParticleTable* particleTable = G4ParticleTable::GetParticleTable();
52 G4String particleName;
53 G4ParticleDefinition* particle = particleTable->FindParticle(particleName = "gamma");
54 fParticleGun->SetParticleDefinition(particle);
55 fParticleGun->SetParticleMomentumDirection(G4ThreeVector(0., 0., 1.));
56 fParticleGun->SetParticleEnergy(6. * MeV);
57 }
58
59 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
60
61 PrimaryGeneratorAction::~PrimaryGeneratorAction()
62 {
63 delete fParticleGun;
64 }
65
66 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
67
68 void PrimaryGeneratorAction::GeneratePrimaries(G4Event* event)
69 {
70 // this function is called at the begining of ecah event
71 //
72
73 // In order to avoid dependence of PrimaryGeneratorAction
74 // on DetectorConstruction class we get Envelope volume
75 // from G4LogicalVolumeStore.
76
77 G4double envSizeXY = 0;
78 G4double envSizeZ = 0;
79
80 if (!fEnvelopeBox) {
81 G4LogicalVolume* envLV = G4LogicalVolumeStore::GetInstance()->GetVolume("Envelope");
82 if (envLV) fEnvelopeBox = dynamic_cast<G4Box*>(envLV->GetSolid());
83 }
84
85 if (fEnvelopeBox) {
86 envSizeXY = fEnvelopeBox->GetXHalfLength() * 2.;
87 envSizeZ = fEnvelopeBox->GetZHalfLength() * 2.;
88 }
89 else {
90 G4ExceptionDescription msg;
91 msg << "Envelope volume of box shape not found.\n";
92 msg << "Perhaps you have changed geometry.\n";
93 msg << "The gun will be place at the center.";
94 G4Exception("PrimaryGeneratorAction::GeneratePrimaries()", "MyCode0002", JustWarning, msg);
95 }
96
97 G4double size = 0.8;
98 G4double x0 = size * envSizeXY * (G4UniformRand() - 0.5);
99 G4double y0 = size * envSizeXY * (G4UniformRand() - 0.5);
100 G4double z0 = -0.5 * envSizeZ;
101
102 fParticleGun->SetParticlePosition(G4ThreeVector(x0, y0, z0));
103
104 fParticleGun->GeneratePrimaryVertex(event);
105 }
106
107 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
108
109 } // namespace B1
110