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G4NeutronElectronElXsc.cc
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25 //
26 // 16.05.17 V. Grichine first implementation
27 
28 
30 #include "G4PhysicalConstants.hh"
31 #include "G4SystemOfUnits.hh"
32 #include "G4DynamicParticle.hh"
33 #include "G4ParticleDefinition.hh"
34 #include "G4ParticleTable.hh"
35 #include "G4IonTable.hh"
36 #include "G4HadTmpUtil.hh"
37 #include "G4NistManager.hh"
38 // #include "G4Integrator.hh"
39 
40 #include "G4PhysicsLogVector.hh"
41 #include "G4PhysicsTable.hh"
42 
43 #include "G4Neutron.hh"
44 #include "G4Electron.hh"
45 
46 
47 using namespace std;
48 using namespace CLHEP;
49 
51  : G4VCrossSectionDataSet("NuElectronCcXsc")
52 {
53  // neutron magneton squared
54 
55  fM = neutron_mass_c2; // neutron mass
56  fM2 = fM*fM;
58  fme2 = fme*fme;
59  fMv2 = 0.7056*GeV*GeV;
60  fee = fme;
61  fee2 = fee*fee;
62  fAm = 0.001;
63 
65  fCofXsc *= 3.6481; // neutron Fm^2(0)
66  fCofXsc /= fM*fM;
67 
68  // G4cout<<"fCofXsc = "<<fCofXsc*GeV/cm2<<" cm2/GeV"<<G4endl;
69 
70  // G4cout<<"hbarc = "<<hbarc/MeV/fermi<<" MeV*fermi"<<G4endl;
71 
72  fCutEnergy = 0.; // default value
73 
74  fEnergyBin = 200;
75  fMinEnergy = 1.*MeV;
76  fMaxEnergy = 10000.*GeV;
77 
79 
80  for( G4int iTkin = 0; iTkin < fEnergyBin; iTkin++) fEnergyXscVector->PutValue(iTkin, fXscArray[iTkin]*microbarn);
81 
82  fBiasingFactor = 1.;
83 
84  // Initialise();
85 }
86 
88 {
89  if( fEnergyXscVector )
90  {
91  delete fEnergyXscVector;
92  fEnergyXscVector = 0;
93  }
94 }
95 
97 //
98 // For neutrons in the precalculated energy interval
99 
100 G4bool
102 {
103  G4bool result = false;
104  G4String pName = aPart->GetDefinition()->GetParticleName();
105  G4double Tkin = aPart->GetKineticEnergy();
106 
107  if( pName == "neutron" &&
108  Tkin >= fMinEnergy &&
109  Tkin <= fMaxEnergy ) result = true;
110 
111  return result;
112 }
113 
115 
117 {
118  G4int iTkin;
119  G4double Tkin, rosxsc, xsc, delta, err=1.e-5;
120  const G4ThreeVector mDir = G4ThreeVector(0.,0.,1.);
123 
125 
126  for( iTkin = 0; iTkin < fEnergyBin; iTkin++)
127  {
128  Tkin = fEnergyXscVector->GetLowEdgeEnergy(iTkin);
129  dP = G4DynamicParticle(pD, mDir, Tkin);
130  rosxsc = GetRosenbluthXsc(&dP, 1, mat);
131  fEnergyXscVector->PutValue(iTkin, rosxsc); // xscV.PutValue(evt, rosxsc); //
132  xsc= fEnergyXscVector->Value(Tkin); // xsc= xscV.GetLowEdgeEnergy(evt); //
133  delta = 0.5*std::abs( (rosxsc-xsc) )/(rosxsc+xsc);
134  if(delta > err) G4cout<<Tkin/GeV<<" GeV, rosxsc = "<<rosxsc/microbarn<<"umb, v-xsc = "<<xsc<<" umb"<<G4endl;
135  }
136  return;
137 }
138 
140 
143  const G4Material*)
144 {
145  G4double result = 0., Tkin;
146 
147  Tkin = aPart->GetKineticEnergy();
148 
149  result = fEnergyXscVector->Value(Tkin);
150 
151  result *= ZZ; // incoherent sum over all element electrons
152 
153  result *= fBiasingFactor;
154 
155  return result;
156 }
157 
159 //
160 // Integration of the Rosenbluth differential xsc
161 
164  const G4Material*)
165 {
166  G4double result = 0., momentum;
167 
168  fee = aPart->GetTotalEnergy()*fme/fM;
169  fee2 = fee*fee;
170  momentum = sqrt( fee2 - fme2 );
172 
173  // G4Integrator<G4NeutronElectronElXsc, G4double(G4NeutronElectronElXsc::*)(G4double)> integral;
174 
175  // result = integral.Legendre96( this, &G4NeutronElectronElXsc::XscIntegrand, 0., 1. );
176 
177  result *= fCofXsc;
178 
179  result *= ZZ; // incoherent sum over all element electrons
180 
181  return result;
182 }
183 
185 //
186 // Rosenbluth relation in the neutron rest frame,
187 // x = sin^2(theta/2), theta is the electron scattering angle
188 // Magnetic form factor in the dipole approximation.
189 
191 {
192  G4double result = 1., q2, znq2, znf, znf2, znf4;
193 
194  znq2 = 1. + 2.*fee*x/fM;
195 
196  q2 = 4.*fee2*x/znq2;
197 
198  znf = 1 + q2/fMv2;
199  znf2 = znf*znf;
200  znf4 = znf2*znf2;
201 
202  result /= ( x + fAm )*znq2*znq2*znf4;
203 
204  result *= ( 1 - x )/( 1 + q2/4./fM2 ) + 2.*x;
205 
206  return result;
207 }
208 
210 //
211 // Rosenbluth xsc in microbarn from 1*MeV to 10*Tev, 200 points
212 
214 1.52681, 1.54903, 1.57123, 1.59341, 1.61556, 1.63769, 1.6598, 1.68189, 1.70396,
215 1.72601, 1.74805, 1.77007, 1.79208, 1.81407, 1.83605, 1.85801, 1.87997, 1.90192,
216 1.92385, 1.94578, 1.96771, 1.98962, 2.01154, 2.03345, 2.05535, 2.07725, 2.09915,
217 2.12105, 2.14295, 2.16485, 2.18675, 2.20865, 2.23055, 2.25244, 2.27433, 2.29621,
218 2.31807, 2.33992, 2.36173, 2.38351, 2.40524, 2.42691, 2.4485, 2.47, 2.49138,
219 2.51262, 2.53369, 2.55457, 2.57524, 2.59565, 2.61577, 2.63559, 2.65505, 2.67414,
220 2.69281, 2.71104, 2.72881, 2.74607, 2.76282, 2.77903, 2.79467, 2.80974, 2.82422,
221 2.83811, 2.85139, 2.86408, 2.87616, 2.88764, 2.89854, 2.90885, 2.91859, 2.92777,
222 2.93641, 2.94453, 2.95213, 2.95924, 2.96588, 2.97207, 2.97782, 2.98316, 2.98811,
223 2.99268, 2.9969, 3.00078, 3.00435, 3.00761, 3.01059, 3.01331, 3.01578, 3.01801,
224 3.02003, 3.02185, 3.02347, 3.02491, 3.02619, 3.02732, 3.0283, 3.02915, 3.02988,
225 3.03049, 3.03099, 3.03139, 3.03169, 3.03191, 3.03203, 3.03208, 3.03205, 3.03195,
226 3.03177, 3.03152, 3.0312, 3.03081, 3.03034, 3.0298, 3.02919, 3.02849, 3.02771,
227 3.02684, 3.02588, 3.02482, 3.02365, 3.02237, 3.02097, 3.01943, 3.01775, 3.0159,
228 3.01389, 3.01169, 3.00929, 3.00666, 3.00379, 3.00065, 2.99722, 2.99347, 2.98936,
229 2.98487, 2.97996, 2.97459, 2.9687, 2.96226, 2.9552, 2.94748, 2.93903, 2.92977,
230 2.91965, 2.90858, 2.89649, 2.88329, 2.86889, 2.85321, 2.83615, 2.81764, 2.7976,
231 2.77594, 2.7526, 2.72754, 2.70071, 2.67209, 2.64171, 2.60957, 2.57575, 2.54031,
232 2.50336, 2.46504, 2.42548, 2.38484, 2.34328, 2.30099, 2.2581, 2.21478, 2.17115,
233 2.12735, 2.08345, 2.03954, 1.99569, 1.95191, 1.90825, 1.86471, 1.82129, 1.77799,
234 1.7348, 1.69171, 1.64869, 1.60575, 1.56286, 1.52, 1.47718, 1.43437, 1.39157,
235 1.34877, 1.30596, 1.26314, 1.22031, 1.17746, 1.13459, 1.0917, 1.04879, 1.00585,
236 0.962892, 0.919908 };