Par02/include/Par02Smearer.hh

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0027 /// \file Par02Smearer.hh
0028 /// \brief Definition of the Par02Smearer class
0029
0030 #ifndef PAR02_SMEARER_H
0031 #define PAR02_SMEARER_H
0032
0033 #include "CLHEP/Random/JamesRandom.h"
0034 #include "CLHEP/Random/RandGauss.h"
0035 #include "Par02Output.hh"
0036
0037 #include "G4Track.hh"
0038 #include "globals.hh"
0039
0040 /// Smearing of the particle momentum or energy.
0041 ///
0042 /// A singleton class used to smear (alter) the particle momentum (for tracking
0043 /// detectors) and energy (for calorimeters). In case the resolution is given,
0044 /// the momentum (energy) is smeared with Gaussian distribution.
0045 /// @author Anna Zaborowska
0046
0047 class Par02Smearer
0048 {
0049   public:
0050     /// Allows the access to the unique Par02Smearer class object.
0051     /// @return A pointer to the Par02Smearer class.
0052     static Par02Smearer* Instance();
0053
0054     /// Smears the momentum with a given resolution.
0055     /// @param aTrack A track to smear.
0056     /// @param aResolution A resolution. Gaussian smearing is done with a
0057     ///                    given resolution as a standard deviation.
0058     G4ThreeVector SmearMomentum(const G4Track* aTrack, G4double aResolution = -1);
0059
0060     /// Smears the energy deposit with a given resolution.
0061     /// @param aTrack A track to smear.
0062     /// @param aResolution A resolution. Gaussian smearing is done with a
0063     ///                    given resolution as a standard deviation.
0064     G4double SmearEnergy(const G4Track* aTrack, G4double aResolution = -1);
0065
0066     /// First possible type of smearing. Smears the momentum with a given resolution.
0067     /// @param aTrackOriginal A track to smear.
0068     /// @param aResolution A resolution taken as a standard deviation of a
0069     ///                    Gaussian distribution.
0070     G4ThreeVector SmearGaussian(const G4Track* aTrackOriginal, G4double aResolution);
0071
0072     /// Returns a random number from a Gaussian distribution.
0073     /// @param aMean The mean of the Gaussian distribution.
0074     /// @param aStandardDeviation The standard deviation of a Gaussian distribution.
0075     G4double Gauss(G4double aMean, G4double aStandardDeviation);
0076
0077   protected:
0078     /// A default constructor.
0079     Par02Smearer();
0080
0081     ~Par02Smearer();
0082
0083   private:
0084     /// A pointer to Par02Smearer object.
0085     static Par02Smearer* fPar02Smearer;
0086
0087     /// CLHEP random engine.
0088     CLHEP::HepRandomEngine* fRandomEngine;
0089
0090     /// CLHEP random engine used in gaussian smearing.
0091     CLHEP::RandGauss* fRandomGauss;
0092 };
0093
0094 #endif