Par02/include/Par02Smearer.hh

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0026 /// \file Par02Smearer.hh
0027 /// \brief Definition of the Par02Smearer class
0028
0029 #ifndef PAR02_SMEARER_H
0030 #define PAR02_SMEARER_H
0031
0032 #include "CLHEP/Random/JamesRandom.h"
0033 #include "CLHEP/Random/RandGauss.h"
0034 #include "Par02Output.hh"
0035
0036 #include "G4Track.hh"
0037 #include "globals.hh"
0038
0039 /// Smearing of the particle momentum or energy.
0040 ///
0041 /// A singleton class used to smear (alter) the particle momentum (for tracking
0042 /// detectors) and energy (for calorimeters). In case the resolution is given,
0043 /// the momentum (energy) is smeared with Gaussian distribution.
0044 /// @author Anna Zaborowska
0045
0046 class Par02Smearer
0047 {
0048   public:
0049     /// Allows the access to the unique Par02Smearer class object.
0050     /// @return A pointer to the Par02Smearer class.
0051     static Par02Smearer* Instance();
0052
0053     /// Smears the momentum with a given resolution.
0054     /// @param aTrack A track to smear.
0055     /// @param aResolution A resolution. Gaussian smearing is done with a
0056     ///                    given resolution as a standard deviation.
0057     G4ThreeVector SmearMomentum(const G4Track* aTrack, G4double aResolution = -1);
0058
0059     /// Smears the energy deposit with a given resolution.
0060     /// @param aTrack A track to smear.
0061     /// @param aResolution A resolution. Gaussian smearing is done with a
0062     ///                    given resolution as a standard deviation.
0063     G4double SmearEnergy(const G4Track* aTrack, G4double aResolution = -1);
0064
0065     /// First possible type of smearing. Smears the momentum with a given resolution.
0066     /// @param aTrackOriginal A track to smear.
0067     /// @param aResolution A resolution taken as a standard deviation of a
0068     ///                    Gaussian distribution.
0069     G4ThreeVector SmearGaussian(const G4Track* aTrackOriginal, G4double aResolution);
0070
0071     /// Returns a random number from a Gaussian distribution.
0072     /// @param aMean The mean of the Gaussian distribution.
0073     /// @param aStandardDeviation The standard deviation of a Gaussian distribution.
0074     G4double Gauss(G4double aMean, G4double aStandardDeviation);
0075
0076   protected:
0077     /// A default constructor.
0078     Par02Smearer();
0079
0080     ~Par02Smearer();
0081
0082   private:
0083     /// A pointer to Par02Smearer object.
0084     static Par02Smearer* fPar02Smearer;
0085
0086     /// CLHEP random engine.
0087     CLHEP::HepRandomEngine* fRandomEngine;
0088
0089     /// CLHEP random engine used in gaussian smearing.
0090     CLHEP::RandGauss* fRandomGauss;
0091 };
0092
0093 #endif