Geant4  10.02
G4ProtonInelasticCrossSection.cc
Go to the documentation of this file.
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 // By JPW, working, but to be cleaned up. @@@
27 // G.Folger, 29-sept-2006: extend to 1TeV, using a constant above 20GeV
28 // 22 Dec 2006 - DHW added isotope dependence
29 // G.Folger, 25-Nov-2009: extend to 100TeV, using a constant above 20GeV
30 // V.Ivanchenko, 18-Aug-2011: migration to new design and cleanup;
31 // make it applicable for Z>1
32 //
33 
35 #include "G4SystemOfUnits.hh"
36 #include "G4DynamicParticle.hh"
37 #include "G4Proton.hh"
38 #include "G4HadTmpUtil.hh"
39 #include "G4NistManager.hh"
40 
42  : G4VCrossSectionDataSet("Axen-Wellisch"),thEnergy(19.8*CLHEP::GeV)
43 {
46 }
47 
49 {}
50 
51 G4bool
53  const G4DynamicParticle* aPart,
54  G4int Z, const G4Material*)
55 {
56  return ((1 < Z) && (aPart->GetDefinition() == theProton));
57 }
58 
60  const G4DynamicParticle* aPart,
61  G4int Z, const G4Material*)
62 {
63  return GetProtonCrossSection(aPart->GetKineticEnergy(), Z);
64 }
65 
67  G4double kineticEnergy, G4int Z)
68 {
69  if(kineticEnergy <= 0.0) { return 0.0; }
70 
71  // constant cross section above ~20GeV
72  if (kineticEnergy > thEnergy) { kineticEnergy = thEnergy; }
73 
75  G4double a13 = G4Pow::GetInstance()->powA(a,-0.3333333333);
76  G4int nOfNeutrons = G4lrint(a) - Z;
77  kineticEnergy /=GeV;
78  G4double alog10E = std::log10(kineticEnergy);
79 
80  static const G4double nuleonRadius=1.36e-15;
81  static const G4double fac=CLHEP::pi*nuleonRadius*nuleonRadius;
82 
83  G4double b0 = 2.247-0.915*(1 - a13);
84  G4double fac1 = b0*(1 - a13);
85  G4double fac2 = 1.;
86  if(nOfNeutrons > 1) { fac2=G4Log((G4double(nOfNeutrons))); }
87  G4double crossSection = 1.0E31*fac*fac2*(1. + 1./a13 - fac1);
88 
89  // high energy correction
90  crossSection *= (1 - 0.15*G4Exp(-kineticEnergy))/(1.0 - 0.0007*a);
91 
92  // first try on low energies: rise
93  G4double ff1= 0.70-0.002*a; // slope of the drop at medium energies.
94  G4double ff2= 1.00+1/a; // start of the slope.
95  G4double ff3= 0.8+18/a-0.002*a; // stephight
96 
97  G4double ff4= 1.0 - (1.0/(1+G4Exp(-8*ff1*(alog10E + 1.37*ff2))));
98 
99  crossSection *= (1 + ff3*ff4);
100 
101  // low energy return to zero
102 
103  ff1=1. - 1./a - 0.001*a; // slope of the rise
104  ff2=1.17 - 2.7/a - 0.0014*a; // start of the rise
105 
106  ff4=-8.*ff1*(alog10E + 2.0*ff2);
107 
108  crossSection *= millibarn/(1. + G4Exp(ff4));
109  return crossSection;
110 }
static G4Pow * GetInstance()
Definition: G4Pow.cc:55
G4double powA(G4double A, G4double y) const
Definition: G4Pow.hh:259
G4double GetKineticEnergy() const
virtual G4double GetElementCrossSection(const G4DynamicParticle *, G4int Z, const G4Material *)
G4ParticleDefinition * GetDefinition() const
G4double a
Definition: TRTMaterials.hh:39
int G4int
Definition: G4Types.hh:78
static G4NistManager * Instance()
bool G4bool
Definition: G4Types.hh:79
virtual G4bool IsElementApplicable(const G4DynamicParticle *aPart, G4int Z, const G4Material *)
static G4Proton * Proton()
Definition: G4Proton.cc:93
static const double GeV
Definition: G4SIunits.hh:214
G4double G4Log(G4double x)
Definition: G4Log.hh:230
G4double G4Exp(G4double initial_x)
Exponential Function double precision.
Definition: G4Exp.hh:183
static const double pi
Definition: G4SIunits.hh:74
int G4lrint(double ad)
Definition: templates.hh:163
G4double GetAtomicMassAmu(const G4String &symb) const
static const double millibarn
Definition: G4SIunits.hh:105
static const G4double fac
double G4double
Definition: G4Types.hh:76
static const G4double b0
G4double GetProtonCrossSection(G4double kineticEnergy, G4int Z)