Geant4  10.00.p01
G4PreCompoundProton.cc
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26 // $Id: G4PreCompoundProton.cc 74903 2013-10-23 16:47:40Z gcosmo $
27 //
28 // -------------------------------------------------------------------
29 //
30 // GEANT4 Class file
31 //
32 //
33 // File name: G4PreCompoundProton
34 //
35 // Author: V.Lara
36 //
37 // Modified:
38 // 21.08.2008 J. M. Quesada added external choice of inverse cross section option
39 // 21.08.2008 J. M. Quesada added external choice for superimposed Coulomb
40 // barrier (if useSICB=true)
41 // 20.08.2010 V.Ivanchenko added G4Pow and G4PreCompoundParameters pointers
42 // use int Z and A and cleanup
43 //
44 
45 #include "G4PreCompoundProton.hh"
46 #include "G4PhysicalConstants.hh"
47 #include "G4SystemOfUnits.hh"
48 #include "G4Proton.hh"
49 #include "G4Log.hh"
50 #include "G4Exp.hh"
51 
53  : G4PreCompoundNucleon(G4Proton::Proton(), &theProtonCoulombBarrier)
54 {
55  ResidualA = GetRestA();
56  ResidualZ = GetRestZ();
57  theA = GetA();
58  theZ = GetZ();
62 }
63 
65 {}
66 
68 {
69  G4double rj = 0.0;
70  if(nParticles > 0) {
71  rj = static_cast<G4double>(nCharged)/static_cast<G4double>(nParticles);
72  }
73  return rj;
74 }
75 
77 //J. M. Quesada (Dec 2007-June 2008): New inverse reaction cross sections
78 //OPT=0 Dostrovski's parameterization
79 //OPT=1 Chatterjee's paramaterization
80 //OPT=2,4 Wellisch's parametarization
81 //OPT=3 Kalbach's parameterization
82 //
84 {
85  ResidualA = GetRestA();
86  ResidualZ = GetRestZ();
87  theA = GetA();
88  theZ = GetZ();
92 
93  if (OPTxs==0) { return GetOpt0(K); }
94  else if( OPTxs==1) { return GetOpt1(K); }
95  else if( OPTxs==2|| OPTxs==4) { return GetOpt2(K); }
96  else if (OPTxs==3) { return GetOpt3(K); }
97  else{
98  std::ostringstream errOs;
99  errOs << "BAD PROTON CROSS SECTION OPTION !!" <<G4endl;
100  throw G4HadronicException(__FILE__, __LINE__, errOs.str());
101  return 0.;
102  }
103 }
104 
106 {
107  G4int aZ = ResidualZ;
108  G4double C = 0.0;
109  if (aZ >= 70)
110  {
111  C = 0.10;
112  }
113  else
114  {
115  C = ((((0.15417e-06*aZ) - 0.29875e-04)*aZ + 0.21071e-02)*aZ
116  - 0.66612e-01)*aZ + 0.98375;
117  }
118  return 1.0 + C;
119 }
120 
122 {
123  return -GetCoulombBarrier();
124 }
125 
126 //********************* OPT=1 : Chatterjee's cross section *********************
127 //(fitting to cross section from Bechetti & Greenles OM potential)
128 
130 {
131  G4double Kc=K;
132 
133  // JMQ xsec is set constat above limit of validity
134  if (K > 50*MeV) { Kc = 50*MeV; }
135 
136  G4double landa, landa0, landa1, mu, mm0, mu1,nu, nu0, nu1, nu2,xs;
137  G4double p, p0, p1, p2,Ec,delta,q,r,ji;
138 
139  p0 = 15.72;
140  p1 = 9.65;
141  p2 = -449.0;
142  landa0 = 0.00437;
143  landa1 = -16.58;
144  mm0 = 244.7;
145  mu1 = 0.503;
146  nu0 = 273.1;
147  nu1 = -182.4;
148  nu2 = -1.872;
149  delta=0.;
150 
151  Ec = 1.44*theZ*ResidualZ/(1.5*ResidualAthrd+delta);
152  p = p0 + p1/Ec + p2/(Ec*Ec);
153  landa = landa0*ResidualA + landa1;
154 
155  G4double resmu1 = g4pow->powZ(ResidualA,mu1);
156  mu = mm0*resmu1;
157  nu = resmu1*(nu0 + nu1*Ec + nu2*(Ec*Ec));
158  q = landa - nu/(Ec*Ec) - 2*p*Ec;
159  r = mu + 2*nu/Ec + p*(Ec*Ec);
160 
161  ji=std::max(Kc,Ec);
162  if(Kc < Ec) { xs = p*Kc*Kc + q*Kc + r;}
163  else {xs = p*(Kc - ji)*(Kc - ji) + landa*Kc + mu + nu*(2 - Kc/ji)/ji ;}
164  if (xs <0.0) {xs=0.0;}
165 
166  return xs;
167 }
168 
169 //************* OPT=2 : Welisch's proton reaction cross section ***************
170 
172 {
173 
174  G4double eekin,ekin,ff1,ff2,ff3,r0,fac,fac1,fac2,b0,xine_th(0);
175 
176  // This is redundant when the Coulomb barrier is overimposed to all
177  // cross sections
178  // It should be kept when Coulomb barrier only imposed at OPTxs=2
179 
180  if(!useSICB && K<=theCoulombBarrier) { return 0.0; }
181 
182  eekin=K;
183  G4int rnneu=ResidualA-ResidualZ;
184  ekin=eekin/1000;
185  r0=1.36*1.e-15;
186  fac=pi*r0*r0;
187  b0=2.247-0.915*(1.-1./ResidualAthrd);
188  fac1=b0*(1.-1./ResidualAthrd);
189  fac2=1.;
190  if(rnneu > 1.5) { fac2 = g4pow->logZ(rnneu); }
191  xine_th= 1.e+31*fac*fac2*(1.+ResidualAthrd-fac1);
192  xine_th=(1.-0.15*G4Exp(-ekin))*xine_th/(1.00-0.0007*ResidualA);
193  ff1=0.70-0.0020*ResidualA;
194  ff2=1.00+1/G4double(ResidualA);
195  ff3=0.8+18/G4double(ResidualA)-0.002*ResidualA;
196  G4double log10E = G4Log(ekin)/g4pow->logZ(10);
197  fac=1.-(1./(1.+G4Exp(-8.*ff1*(log10E + 1.37*ff2))));
198  xine_th=xine_th*(1.+ff3*fac);
199  ff1=1.-1/G4double(ResidualA)-0.001*ResidualA;
200  ff2=1.17-2.7/G4double(ResidualA)-0.0014*ResidualA;
201  fac=-8.*ff1*(log10E + 2.0*ff2);
202  fac=1./(1.+G4Exp(fac));
203  xine_th=xine_th*fac;
204  if (xine_th < 0.0){
205  std::ostringstream errOs;
206  G4cout<<"WARNING: negative Wellisch cross section "<<G4endl;
207  errOs << "RESIDUAL: A=" << ResidualA << " Z=" << ResidualZ <<G4endl;
208  errOs <<" xsec("<<ekin<<" MeV) ="<<xine_th <<G4endl;
209  throw G4HadronicException(__FILE__, __LINE__, errOs.str());
210  }
211  return xine_th;
212 }
213 
214 // *********** OPT=3 : Kalbach's cross sections (from PRECO code)*************
216 {
217  // ** p from becchetti and greenlees (but modified with sub-barrier
218  // ** correction function and xp2 changed from -449)
219 
220  G4double landa, landa0, landa1, mu, mm0, mu1,nu, nu0, nu1, nu2;
221  G4double p, p0, p1, p2;
222  p0 = 15.72;
223  p1 = 9.65;
224  p2 = -300.;
225  landa0 = 0.00437;
226  landa1 = -16.58;
227  mm0 = 244.7;
228  mu1 = 0.503;
229  nu0 = 273.1;
230  nu1 = -182.4;
231  nu2 = -1.872;
232 
233  // parameters for proton cross section refinement
234  /*
235  G4double afit,bfit,a2,b2;
236  afit=-0.0785656;
237  bfit=5.10789;
238  a2= -0.00089076;
239  b2= 0.0231597;
240  */
241 
242  G4double ec,ecsq,xnulam,etest(0.),ra(0.),a,w,c,signor(1.),signor2,sig;
243  G4double b,ecut,cut,ecut2,geom,elab;
244 
245  G4double flow = 1.e-18;
246  G4double spill= 1.e+18;
247 
248  if (ResidualA <= 60) { signor = 0.92; }
249  else if (ResidualA < 100) { signor = 0.8 + ResidualA*0.002; }
250 
251  ec = 1.44 * theZ * ResidualZ / (1.5*ResidualAthrd+ra);
252  ecsq = ec * ec;
253  p = p0 + p1/ec + p2/ecsq;
254  landa = landa0*ResidualA + landa1;
255  a = g4pow->powZ(ResidualA,mu1);
256  mu = mm0 * a;
257  nu = a* (nu0+nu1*ec+nu2*ecsq);
258 
259  c =std::min(3.15,ec*0.5);
260  w = 0.7 * c / 3.15;
261 
262  xnulam = nu / landa;
263  if (xnulam > spill) { xnulam=0.; }
264  if (xnulam >= flow) { etest =std::sqrt(xnulam) + 7.; }
265 
266  a = -2.*p*ec + landa - nu/ecsq;
267  b = p*ecsq + mu + 2.*nu/ec;
268  ecut = 0.;
269  cut = a*a - 4.*p*b;
270  if (cut > 0.) { ecut = std::sqrt(cut); }
271  ecut = (ecut-a) / (p+p);
272  ecut2 = ecut;
273  //JMQ 290310 for avoiding unphysical increase below minimum (at ecut)
274  // ecut<0 means that there is no cut with energy axis, i.e. xs is set
275  // to 0 bellow minimum
276  // if (cut < 0.) ecut2 = ecut - 2.;
277  if (cut < 0.) { ecut2 = ecut; }
278  elab = K * FragmentA /G4double(ResidualA);
279  sig = 0.;
280  if (elab <= ec) { //start for E<Ec
281  if (elab > ecut2) { sig = (p*elab*elab+a*elab+b) * signor; }
282 
283  signor2 = (ec-elab-c) / w;
284  signor2 = 1. + G4Exp(signor2);
285  sig = sig / signor2;
286  } //end for E<=Ec
287  else{ //start for E>Ec
288  sig = (landa*elab+mu+nu/elab) * signor;
289  geom = 0.;
290 
291  if (xnulam < flow || elab < etest)
292  {
293  if (sig <0.0) {sig=0.0;}
294  return sig;
295  }
296  geom = std::sqrt(theA*K);
297  geom = 1.23*ResidualAthrd + ra + 4.573/geom;
298  geom = 31.416 * geom * geom;
299  sig = std::max(geom,sig);
300 
301  } //end for E>Ec
302  return sig;
303 }
G4double GetOpt3(G4double K)
static const double MeV
Definition: G4SIunits.hh:193
static const G4double fac
G4double ResidualA13() const
const G4double pi
virtual G4double GetRj(G4int NumberParticles, G4int NumberCharged)
G4int GetA() const
G4double GetOpt0(G4double ekin)
G4double a
Definition: TRTMaterials.hh:39
virtual G4double CrossSection(G4double ekin)
int G4int
Definition: G4Types.hh:78
G4double logZ(G4int Z) const
Definition: G4Pow.hh:165
G4GLOB_DLL std::ostream G4cout
G4double Z13(G4int Z) const
Definition: G4Pow.hh:129
virtual G4double GetBeta()
G4int GetRestZ() const
virtual G4double GetAlpha()
G4double GetCoulombBarrier() const
G4double G4Log(G4double x)
Definition: G4Log.hh:227
G4double G4Exp(G4double initial_x)
Exponential Function double precision.
Definition: G4Exp.hh:180
T max(const T t1, const T t2)
brief Return the largest of the two arguments
G4double GetOpt1(G4double K)
T min(const T t1, const T t2)
brief Return the smallest of the two arguments
G4int GetRestA() const
#define G4endl
Definition: G4ios.hh:61
G4int GetZ() const
G4double powZ(G4int Z, G4double y) const
Definition: G4Pow.hh:258
double G4double
Definition: G4Types.hh:76
static const G4double b0
G4double GetOpt2(G4double K)