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26 //
27 /// \file Par02Smearer.hh
28 /// \brief Definition of the Par02Smearer class
29
30 #ifndef PAR02_SMEARER_H
31 #define PAR02_SMEARER_H
32
33 #include "CLHEP/Random/JamesRandom.h"
34 #include "CLHEP/Random/RandGauss.h"
35 #include "Par02Output.hh"
36
37 #include "G4Track.hh"
38 #include "globals.hh"
39
40 /// Smearing of the particle momentum or energy.
41 ///
42 /// A singleton class used to smear (alter) the particle momentum (for tracking
43 /// detectors) and energy (for calorimeters). In case the resolution is given,
44 /// the momentum (energy) is smeared with Gaussian distribution.
45 /// @author Anna Zaborowska
46
47 class Par02Smearer
48 {
49 public:
50 /// Allows the access to the unique Par02Smearer class object.
51 /// @return A pointer to the Par02Smearer class.
52 static Par02Smearer* Instance();
53
54 /// Smears the momentum with a given resolution.
55 /// @param aTrack A track to smear.
56 /// @param aResolution A resolution. Gaussian smearing is done with a
57 /// given resolution as a standard deviation.
58 G4ThreeVector SmearMomentum(const G4Track* aTrack, G4double aResolution = -1);
59
60 /// Smears the energy deposit with a given resolution.
61 /// @param aTrack A track to smear.
62 /// @param aResolution A resolution. Gaussian smearing is done with a
63 /// given resolution as a standard deviation.
64 G4double SmearEnergy(const G4Track* aTrack, G4double aResolution = -1);
65
66 /// First possible type of smearing. Smears the momentum with a given resolution.
67 /// @param aTrackOriginal A track to smear.
68 /// @param aResolution A resolution taken as a standard deviation of a
69 /// Gaussian distribution.
70 G4ThreeVector SmearGaussian(const G4Track* aTrackOriginal, G4double aResolution);
71
72 /// Returns a random number from a Gaussian distribution.
73 /// @param aMean The mean of the Gaussian distribution.
74 /// @param aStandardDeviation The standard deviation of a Gaussian distribution.
75 G4double Gauss(G4double aMean, G4double aStandardDeviation);
76
77 protected:
78 /// A default constructor.
79 Par02Smearer();
80
81 ~Par02Smearer();
82
83 private:
84 /// A pointer to Par02Smearer object.
85 static Par02Smearer* fPar02Smearer;
86
87 /// CLHEP random engine.
88 CLHEP::HepRandomEngine* fRandomEngine;
89
90 /// CLHEP random engine used in gaussian smearing.
91 CLHEP::RandGauss* fRandomGauss;
92 };
93
94 #endif
95