source: trunk/source/processes/electromagnetic/highenergy/src/G4eeToTwoPiModel.cc@ 1192

Last change on this file since 1192 was 1055, checked in by garnier, 17 years ago

maj sur la beta de geant 4.9.3
File size: 4.7 KB
Line 
1//
2// ********************************************************************
3// * License and Disclaimer *
4// * *
5// * The Geant4 software is copyright of the Copyright Holders of *
6// * the Geant4 Collaboration. It is provided under the terms and *
7// * conditions of the Geant4 Software License, included in the file *
8// * LICENSE and available at http://cern.ch/geant4/license . These *
9// * include a list of copyright holders. *
10// * *
11// * Neither the authors of this software system, nor their employing *
12// * institutes,nor the agencies providing financial support for this *
13// * work make any representation or warranty, express or implied, *
14// * regarding this software system or assume any liability for its *
15// * use. Please see the license in the file LICENSE and URL above *
16// * for the full disclaimer and the limitation of liability. *
17// * *
18// * This code implementation is the result of the scientific and *
19// * technical work of the GEANT4 collaboration. *
20// * By using, copying, modifying or distributing the software (or *
21// * any work based on the software) you agree to acknowledge its *
22// * use in resulting scientific publications, and indicate your *
23// * acceptance of all terms of the Geant4 Software license. *
24// ********************************************************************
25//
26// $Id: G4eeToTwoPiModel.cc,v 1.7 2009/02/20 16:38:33 vnivanch Exp $
27// GEANT4 tag $Name: geant4-09-03-beta-cand-01 $
28//
29// -------------------------------------------------------------------
30//
31// GEANT4 Class header file
32//
33//
34// File name: G4eeToTwoPiModel
35//
36// Author: Vladimir Ivanchenko
37//
38// Creation date: 25.10.2003
39//
40// Modifications:
41//
42//
43// -------------------------------------------------------------------
44//
45
46
47//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
48//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
49
50#include "G4eeToTwoPiModel.hh"
51#include "Randomize.hh"
52#include "G4PionPlus.hh"
53#include "G4PionMinus.hh"
54#include "G4DynamicParticle.hh"
55#include "G4PhysicsVector.hh"
56#include "G4PhysicsLinearVector.hh"
57#include "G4eeCrossSections.hh"
58
59//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
60
61using namespace std;
62
63G4eeToTwoPiModel::G4eeToTwoPiModel(G4eeCrossSections* cr):
64 cross(cr)
65{
66 massPi = G4PionPlus::PionPlus()->GetPDGMass();
67 massRho = 775.5*MeV;
68}
69
70//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
71
72G4eeToTwoPiModel::~G4eeToTwoPiModel()
73{}
74
75//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
76
77G4double G4eeToTwoPiModel::ThresholdEnergy() const
78{
79 return 2.0*massPi;
80}
81
82//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
83
84G4double G4eeToTwoPiModel::PeakEnergy() const
85{
86 return massRho;
87}
88
89//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
90
91G4double G4eeToTwoPiModel::ComputeCrossSection(G4double e) const
92{
93 G4double ee = std::min(HighEnergy(),e);
94 return cross->CrossSection2pi(ee);
95}
96
97//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
98
99G4PhysicsVector* G4eeToTwoPiModel::PhysicsVector(G4double emin,
100 G4double emax) const
101{
102 G4double tmin = std::max(emin, 2.0*massPi);
103 G4double tmax = std::max(tmin, emax);
104 G4int nbins = (G4int)((tmax - tmin)/(5.*MeV));
105 G4PhysicsVector* v = new G4PhysicsLinearVector(emin,emax,nbins);
106 v->SetSpline(true);
107 return v;
108}
109
110//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
111
112void G4eeToTwoPiModel::SampleSecondaries(std::vector<G4DynamicParticle*>* newp,
113 G4double e, const G4ThreeVector& direction)
114{
115
116 G4double tkin = 0.5*e - massPi;
117 if(tkin < 0.0) tkin = 0.0;
118 G4double cost;
119 do {
120 cost = 2.0*G4UniformRand() - 1.0;
121 } while( G4UniformRand() > 1.0 - cost*cost );
122
123 G4double sint = sqrt(1.0 - cost*cost);
124 G4double phi = twopi * G4UniformRand();
125
126 G4ThreeVector dir(sint*cos(phi),sint*sin(phi), cost);
127 dir.rotateUz(direction);
128
129 // create G4DynamicParticle objects
130 G4DynamicParticle* pip =
131 new G4DynamicParticle(G4PionPlus::PionPlus(),dir,tkin);
132 G4DynamicParticle* pin =
133 new G4DynamicParticle(G4PionMinus::PionMinus(),-dir,tkin);
134 newp->push_back(pip);
135 newp->push_back(pin);
136}
137
138//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
139
Note: See TracBrowser for help on using the repository browser.