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Par02Smearer.cc
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29 
30 #include "Par02Smearer.hh"
31 #include "Par02PrimaryParticleInformation.hh"
32 #include "G4PrimaryParticle.hh"
33 #include "G4UnitsTable.hh"
34 #include "G4SystemOfUnits.hh"
35 #include "G4TransportationManager.hh"
36 #include "G4FieldManager.hh"
37 #include "G4UniformMagField.hh"
38 #include <ctime>
39 
40 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
41 
42 Par02Smearer* Par02Smearer::fPar02Smearer = 0;
43 
44 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
45 
46 Par02Smearer::Par02Smearer() {
47  time_t seed = time( NULL );
48  fRandomEngine = new CLHEP::HepJamesRandom( static_cast< long >( seed ) );
49  fRandomGauss = new CLHEP::RandGauss( fRandomEngine );
50 }
51 
52 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
53 
54 Par02Smearer::~Par02Smearer() {}
55 
56 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
57 
58 Par02Smearer* Par02Smearer::Instance() {
59  if ( ! fPar02Smearer ) {
60  fPar02Smearer = new Par02Smearer();
61  }
62  return fPar02Smearer;
63 }
64 
65 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
66 
67 G4ThreeVector Par02Smearer::SmearMomentum( const G4Track* aTrackOriginal,
68  G4double aResolution ) {
69  return SmearGaussian( aTrackOriginal, aResolution );
70 }
71 
72 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
73 
74 G4double Par02Smearer::SmearEnergy( const G4Track* aTrackOriginal,
75  G4double aResolution ) {
76  G4double newE = -1.0;
77  while ( newE < 0.0 ) { // To ensure that the resulting value is not negative
78  // (vital for energy smearing, does not change direction
79  // for momentum smearing)
80  if ( aResolution != -1.0 ) {
81  newE = aTrackOriginal->GetKineticEnergy() * Gauss( 1.0, aResolution );
82  } else {
83  newE = aTrackOriginal->GetKineticEnergy();
84  }
85  }
86  return newE;
87 }
88 
89 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
90 
91 G4ThreeVector Par02Smearer::SmearGaussian( const G4Track* aTrackOriginal,
92  G4double aResolution ) {
93  G4ThreeVector originP = aTrackOriginal->GetMomentum();
94  G4ThreeVector originPos = aTrackOriginal->GetPosition();
95  G4double rdm = Gauss( 1.0, aResolution );
96  G4ThreeVector smearedMom( originP.x()*rdm, originP.y()*rdm, originP.z()*rdm );
97  return smearedMom;
98 }
99 
100 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
101 
102 G4double Par02Smearer::Gauss( G4double aMean, G4double aStandardDeviation ) {
103  return fRandomGauss->fire( aMean, aStandardDeviation );
104 }
105 
106 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
107