include/Geant4/G4VAnnihilationCollision.hh

0001 //
0002 // ********************************************************************
0003 // * License and Disclaimer                                           *
0004 // *                                                                  *
0005 // * The  Geant4 software  is  copyright of the Copyright Holders  of *
0006 // * the Geant4 Collaboration.  It is provided  under  the terms  and *
0007 // * conditions of the Geant4 Software License,  included in the file *
0008 // * LICENSE and available at  http://cern.ch/geant4/license .  These *
0009 // * include a list of copyright holders.                             *
0010 // *                                                                  *
0011 // * Neither the authors of this software system, nor their employing *
0012 // * institutes,nor the agencies providing financial support for this *
0013 // * work  make  any representation or  warranty, express or implied, *
0014 // * regarding  this  software system or assume any liability for its *
0015 // * use.  Please see the license in the file  LICENSE  and URL above *
0016 // * for the full disclaimer and the limitation of liability.         *
0017 // *                                                                  *
0018 // * This  code  implementation is the result of  the  scientific and *
0019 // * technical work of the GEANT4 collaboration.                      *
0020 // * By using,  copying,  modifying or  distributing the software (or *
0021 // * any work based  on the software)  you  agree  to acknowledge its *
0022 // * use  in  resulting  scientific  publications,  and indicate your *
0023 // * acceptance of all terms of the Geant4 Software license.          *
0024 // ********************************************************************
0025 //
0026 //
0027 // -------------------------------------------------------------------
0028 //      GEANT4 Class file
0029 //
0030 //      For information related to this code contact:
0031 //
0032 //      File name:     G4VElasticCollision
0033 //
0034 //      Author:        Maria Grazia Pia
0035 //
0036 //      Creation date: 15 April 1999
0037 //
0038 //      Modifications:
0039 //
0040 // -------------------------------------------------------------------
0041
0042 #ifndef G4VANNIHILATIONCOLLISION_HH
0043 #define G4VANNIHILATIONCOLLISION_HH
0044
0045 #include "globals.hh"
0046 #include "G4Log.hh"
0047 #include "G4VCollision.hh"
0048 #include "G4VCrossSectionSource.hh"
0049 #include "G4VAngularDistribution.hh"
0050 #include "G4KineticTrackVector.hh"
0051
0052 class G4KineticTrack;
0053
0054
0055 class G4VAnnihilationCollision : public G4VCollision
0056 {
0057
0058 public:
0059
0060   G4VAnnihilationCollision();
0061
0062   virtual ~G4VAnnihilationCollision();
0063
0064   G4bool operator==(const G4VAnnihilationCollision &right) const;
0065   G4bool operator!=(const G4VAnnihilationCollision &right) const;
0066
0067   virtual G4KineticTrackVector* FinalState(const G4KineticTrack& trk1,
0068                           const G4KineticTrack& trk2) const;
0069   virtual const G4VAngularDistribution* GetAngularDistribution() const
0070   {
0071     return theAngularDistribution;
0072   }
0073
0074 protected:
0075
0076   virtual const G4ParticleDefinition* GetOutgoingParticle(const G4KineticTrack& trk1,
0077                               const G4KineticTrack& trk2) const = 0;
0078
0079 private:
0080
0081   double BrWigInt0(const double x, const double gamma, const double m0) const
0082     { return 2.0*gamma*std::atan( 2.0 * (x-m0)/ gamma  ); }
0083
0084   G4double BrWigInt1(const G4double x, const G4double gamma, const G4double m0) const
0085     { return 0.5*gamma*gamma*G4Log( (x-m0)*(x-m0)+gamma*gamma/4.0 ) + m0*BrWigInt0(x,gamma,m0); }
0086
0087   double BrWigInv(const double x, const double gamma, const double m0) const
0088     { return 0.5*gamma*std::tan( 0.5*x/gamma )+m0; }
0089
0090   double SampleResonanceMass(const double poleMass,
0091                  const double width,
0092                  const double minMass,
0093                  const double maxMass) const;
0094 private:
0095
0096  G4VAngularDistribution * theAngularDistribution;
0097
0098 };
0099
0100
0101
0102
0103 #endif