source: trunk/source/processes/hadronic/models/de_excitation/evaporation/src/G4He3EvaporationProbability.cc @ 1007

Last change on this file since 1007 was 1007, checked in by garnier, 15 years ago

update to geant4.9.2
File size: 7.9 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//J.M. Quesada (August2008). Based on:
27//
28// Hadronic Process: Nuclear De-excitations
29// by V. Lara (Oct 1998)
30//
31// Modif (03 September 2008) by J. M. Quesada for external choice of inverse
32// cross section option
33
34#include "G4He3EvaporationProbability.hh"
35
36G4He3EvaporationProbability::G4He3EvaporationProbability() :
37   G4EvaporationProbability(3,2,2,&theCoulombBarrier) // A,Z,Gamma,&theCoulombBarrier
38{
39
40}
41
42G4He3EvaporationProbability::G4He3EvaporationProbability(const G4He3EvaporationProbability &) : G4EvaporationProbability()
43{
44    throw G4HadronicException(__FILE__, __LINE__, "G4He3EvaporationProbability::copy_constructor meant to not be accessable");
45}
46
47
48
49
50const G4He3EvaporationProbability & G4He3EvaporationProbability::
51operator=(const G4He3EvaporationProbability &)
52{
53    throw G4HadronicException(__FILE__, __LINE__, "G4He3EvaporationProbability::operator= meant to not be accessable");
54    return *this;
55}
56
57
58G4bool G4He3EvaporationProbability::operator==(const G4He3EvaporationProbability &) const
59{
60    return false;
61}
62
63G4bool G4He3EvaporationProbability::operator!=(const G4He3EvaporationProbability &) const
64{
65    return true;
66}
67
68  G4double G4He3EvaporationProbability::CalcAlphaParam(const G4Fragment & fragment) 
69  { return 1.0 + CCoeficient(static_cast<G4double>(fragment.GetZ()-GetZ()));}
70       
71  G4double G4He3EvaporationProbability::CalcBetaParam(const G4Fragment & ) 
72  { return 0.0; }
73
74
75G4double G4He3EvaporationProbability::CCoeficient(const G4double aZ) 
76{
77    // Data comes from
78    // Dostrovsky, Fraenkel and Friedlander
79    // Physical Review, vol 116, num. 3 1959
80    //
81    // const G4int size = 5;
82    // G4double Zlist[5] = { 10.0, 20.0, 30.0, 50.0, 70.0};
83    //  G4double Calpha[5] = { 0.10, 0.10, 0.10, 0.08, 0.06};
84    // C for He3 is equal to C for alpha times 4/3
85    G4double C = 0.0;
86       
87       
88    if (aZ <= 30) {
89        C = 0.10;
90    } else if (aZ <= 50) {
91        C = 0.1 + -((aZ-50.)/20.)*0.02;
92    } else if (aZ < 70) {
93        C = 0.08 + -((aZ-70.)/20.)*0.02;
94    } else {
95        C = 0.06;
96    }
97    return C*(4.0/3.0);
98}
99
100///////////////////////////////////////////////////////////////////////////////////
101//J. M. Quesada (Dec 2007-June 2008): New inverse reaction cross sections
102//OPT=0 Dostrovski's parameterization
103//OPT=1,2 Chatterjee's paramaterization
104//OPT=3,4 Kalbach's parameterization
105//
106 G4double G4He3EvaporationProbability::CrossSection(const  G4Fragment & fragment, const  G4double K)
107{
108       theA=GetA();
109       theZ=GetZ();
110       ResidualA=fragment.GetA()-theA;
111       ResidualZ=fragment.GetZ()-theZ; 
112 
113       ResidualAthrd=std::pow(ResidualA,0.33333);
114       FragmentA=fragment.GetA();
115       FragmentAthrd=std::pow(FragmentA,0.33333);
116
117
118       if (OPTxs==0) {std::ostringstream errOs;
119         errOs << "We should'n be here (OPT =0) at evaporation cross section calculation (He3's)!!"  <<G4endl;
120         throw G4HadronicException(__FILE__, __LINE__, errOs.str());
121         return 0.;}
122       if( OPTxs==1 || OPTxs==2) return G4He3EvaporationProbability::GetOpt12( K);
123       else if (OPTxs==3 || OPTxs==4)  return G4He3EvaporationProbability::GetOpt34( K);
124       else{
125         std::ostringstream errOs;
126         errOs << "BAD He3's CROSS SECTION OPTION AT EVAPORATION!!"  <<G4endl;
127         throw G4HadronicException(__FILE__, __LINE__, errOs.str());
128         return 0.;
129       }
130}
131//
132//********************* OPT=1,2 : Chatterjee's cross section ************************
133//(fitting to cross section from Bechetti & Greenles OM potential)
134
135G4double G4He3EvaporationProbability::GetOpt12(const  G4double K)
136{
137
138G4double Kc=K;
139
140// JMQ xsec is set constat above limit of validity
141 if (K>50) Kc=50;
142
143 G4double landa ,mu ,nu ,p , Ec,q,r,ji,xs;
144
145 G4double     p0 = -3.06;
146 G4double     p1 = 278.5;
147 G4double     p2 = -1389.;
148 G4double     landa0 = -0.00535;
149 G4double     landa1 = -11.16;
150 G4double     mu0 = 555.5;
151 G4double     mu1 = 0.40;
152 G4double     nu0 = 687.4;
153 G4double     nu1 = -476.3;
154 G4double     nu2 = 0.509;   
155 G4double     delta=1.2;             
156
157      Ec = 1.44*theZ*ResidualZ/(1.5*ResidualAthrd+delta);
158      p = p0 + p1/Ec + p2/(Ec*Ec);
159      landa = landa0*ResidualA + landa1;
160      mu = mu0*std::pow(ResidualA,mu1);
161      nu = std::pow(ResidualA,mu1)*(nu0 + nu1*Ec + nu2*(Ec*Ec));
162      q = landa - nu/(Ec*Ec) - 2*p*Ec;
163      r = mu + 2*nu/Ec + p*(Ec*Ec);
164
165   ji=std::max(Kc,Ec);
166   if(Kc < Ec) { xs = p*Kc*Kc + q*Kc + r;}
167   else {xs = p*(Kc - ji)*(Kc - ji) + landa*Kc + mu + nu*(2 - Kc/ji)/ji ;}
168   
169   if (xs <0.0) {xs=0.0;}
170             
171   return xs;
172
173}
174
175// *********** OPT=3,4 : Kalbach's cross sections (from PRECO code)*************
176G4double G4He3EvaporationProbability::GetOpt34(const  G4double K)
177//c     ** 3he from o.m. of gibson et al
178{
179 
180  G4double landa, mu, nu, p , signor(1.),sig;
181  G4double ec,ecsq,xnulam,etest(0.),a; 
182  G4double b,ecut,cut,ecut2,geom,elab;
183 
184 
185  G4double     flow = 1.e-18;
186  G4double     spill= 1.e+18;
187
188
189  G4double     p0 = -2.88;
190  G4double     p1 = 205.6;
191  G4double     p2 = -1487.;
192  G4double     landa0 = 0.00459;
193  G4double     landa1 = -8.93;
194  G4double     mu0 = 611.2;
195  G4double     mu1 = 0.35;
196  G4double     nu0 = 473.8;
197  G4double     nu1 = -468.2;
198  G4double     nu2 = -2.225;     
199 
200  G4double      ra=0.80;
201 
202  ec = 1.44 * theZ * ResidualZ / (1.5*ResidualAthrd+ra);
203  ecsq = ec * ec;
204  p = p0 + p1/ec + p2/ecsq;
205  landa = landa0*ResidualA + landa1;
206  a = std::pow(ResidualA,mu1);
207  mu = mu0 * a;
208  nu = a* (nu0+nu1*ec+nu2*ecsq); 
209  xnulam = nu / landa;
210  if (xnulam > spill) xnulam=0.;
211  if (xnulam >= flow) etest = 1.2 *std::sqrt(xnulam);
212 
213  a = -2.*p*ec + landa - nu/ecsq;
214  b = p*ecsq + mu + 2.*nu/ec;
215  ecut = 0.;
216  cut = a*a - 4.*p*b;
217  if (cut > 0.) ecut = std::sqrt(cut);
218  ecut = (ecut-a) / (p+p);
219  ecut2 = ecut;
220  if (cut < 0.) ecut2 = ecut - 2.;
221  elab = K * FragmentA / ResidualA;
222  sig = 0.;
223 
224  if (elab <= ec) { //start for E<Ec
225    if (elab > ecut2)  sig = (p*elab*elab+a*elab+b) * signor;   
226  }           //end for E<Ec
227  else {           //start for E>Ec
228    sig = (landa*elab+mu+nu/elab) * signor;
229    geom = 0.;
230    if (xnulam < flow || elab < etest) return sig;
231    geom = std::sqrt(theA*K);
232    geom = 1.23*ResidualAthrd + ra + 4.573/geom;
233    geom = 31.416 * geom * geom;
234    sig = std::max(geom,sig);
235  }           //end for E>Ec
236  return sig;
237 
238}
239
240//   ************************** end of cross sections *******************************
241
Note: See TracBrowser for help on using the repository browser.