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G4QPionPlusNuclearCrossSection.cc
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27 // The lust update: M.V. Kossov, CERN/ITEP(Moscow) 17-June-02
28 // GEANT4 tag $Name: not supported by cvs2svn $
29 //
30 //
31 // G4 Physics class: G4QPionPlusNuclearCrossSection for gamma+A cross sections
32 // Created: M.V. Kossov, CERN/ITEP(Moscow), 20-Dec-03
33 // The last update: M.V. Kossov, CERN/ITEP (Moscow) 15-Feb-04
34 // --------------------------------------------------------------------------------
35 // ****************************************************************************************
36 // This Header is a part of the CHIPS physics package (author: M. Kosov)
37 // ****************************************************************************************
38 // Short description: CHIPS cross-sections for pi(plus)-nuclear interactions
39 // -------------------------------------------------------------------------------------
40 //
41 //#define debug
42 //#define pdebug
43 //#define debug3
44 //#define debugn
45 //#define debugs
46 
47 #include "G4QPionPlusNuclearCrossSection.hh"
48 #include "G4SystemOfUnits.hh"
49 
50 // Initialization of the
51 G4double* G4QPionPlusNuclearCrossSection::lastLEN=0; // Pointer to lastArray of LowEn CS
52 G4double* G4QPionPlusNuclearCrossSection::lastHEN=0; // Pointer to lastArray of HighEn CS
53 G4int G4QPionPlusNuclearCrossSection::lastN=0; // The last N of calculated nucleus
54 G4int G4QPionPlusNuclearCrossSection::lastZ=0; // The last Z of calculated nucleus
55 G4double G4QPionPlusNuclearCrossSection::lastP=0.; // Last used in cross section Momentum
56 G4double G4QPionPlusNuclearCrossSection::lastTH=0.; // Last threshold momentum
57 G4double G4QPionPlusNuclearCrossSection::lastCS=0.; // Last value of the Cross Section
58 G4int G4QPionPlusNuclearCrossSection::lastI=0; // The last position in the DAMDB
59 std::vector<G4double*>* G4QPionPlusNuclearCrossSection::LEN = new std::vector<G4double*>;
60 std::vector<G4double*>* G4QPionPlusNuclearCrossSection::HEN = new std::vector<G4double*>;
61 
62 // Returns Pointer to the G4VQCrossSection class
63 G4VQCrossSection* G4QPionPlusNuclearCrossSection::GetPointer()
64 {
65  static G4QPionPlusNuclearCrossSection theCrossSection; //**Static body of Cross Section**
66  return &theCrossSection;
67 }
68 
69 G4QPionPlusNuclearCrossSection::~G4QPionPlusNuclearCrossSection()
70 {
71  G4int lens=LEN->size();
72  for(G4int i=0; i<lens; ++i) delete[] (*LEN)[i];
73  delete LEN;
74  G4int hens=HEN->size();
75  for(G4int i=0; i<hens; ++i) delete[] (*HEN)[i];
76  delete HEN;
77 }
78 
79 // The main member function giving the collision cross section (P is in IU, CS is in mb)
80 // Make pMom in independent units ! (Now it is MeV)
81 G4double G4QPionPlusNuclearCrossSection::GetCrossSection(G4bool fCS, G4double pMom,
82  G4int tgZ, G4int tgN, G4int PDG)
83 {
84  //A.R.23-Oct-2012 Shadowed variable static G4double tolerance=0.001; // Tolerance (0.1%) to consider as "the same mom"
85  static G4int j; // A#0f Z/N-records already tested in AMDB
86  static std::vector <G4int> colN; // Vector of N for calculated nuclei (isotops)
87  static std::vector <G4int> colZ; // Vector of Z for calculated nuclei (isotops)
88  static std::vector <G4double> colP; // Vector of last momenta for the reaction
89  static std::vector <G4double> colTH; // Vector of energy thresholds for the reaction
90  static std::vector <G4double> colCS; // Vector of last cross sections for the reaction
91  // ***---*** End of the mandatory Static Definitions of the Associative Memory ***---***
92 #ifdef debug
93  G4cout<<"G4QPipCS::GetCS:>>>f="<<fCS<<", p="<<pMom<<", Z="<<tgZ<<"("<<lastZ<<") ,N="<<tgN
94  <<"("<<lastN<<"),PDG=211, thresh="<<lastTH<<",Sz="<<colN.size()<<G4endl;
95 #endif
96  if(PDG!=211) G4cout<<"-Warning-G4QPionPlusCS::GetCS:**Not a PiPlus**,PDG="<<PDG<<G4endl;
97  G4bool in=false; // By default the isotope must be found in the AMDB
98  if(tgN!=lastN || tgZ!=lastZ) // The nucleus was not the last used isotope
99  {
100  in = false; // By default the isotope haven't be found in AMDB
101  lastP = 0.; // New momentum history (nothing to compare with)
102  lastN = tgN; // The last N of the calculated nucleus
103  lastZ = tgZ; // The last Z of the calculated nucleus
104  lastI = colN.size(); // Size of the Associative Memory DB in the heap
105  j = 0; // A#0f records found in DB for this projectile
106 #ifdef debug
107  G4cout<<"G4QPipCS::GetCS: the amount of records in the AMDB lastI="<<lastI<<G4endl;
108 #endif
109  if(lastI) for(G4int i=0; i<lastI; i++) // AMDB exists, try to find the (Z,N) isotope
110  {
111  if(colN[i]==tgN && colZ[i]==tgZ) // Try the record "i" in the AMDB
112  {
113  lastI=i; // Remember the index for future fast/last use
114  lastTH =colTH[i]; // The last THreshold (A-dependent)
115 #ifdef debug
116  G4cout<<"G4QPipCS::GetCS:*Found*P="<<pMom<<",Threshold="<<lastTH<<",j="<<j<<G4endl;
117 #endif
118  if(pMom<=lastTH)
119  {
120 #ifdef debug
121  G4cout<<"G4QPipCS::GCS:Found,P="<<pMom<<" < Threshold="<<lastTH<<",CS=0"<<G4endl;
122 #endif
123  return 0.; // Energy is below the Threshold value
124  }
125  lastP =colP [i]; // Last Momentum (A-dependent)
126  lastCS =colCS[i]; // Last CrossSect (A-dependent)
127  if(std::fabs(lastP-pMom)<tolerance*pMom)
128  //if(lastP==pMom) // VI do not use tolerance
129  {
130 #ifdef debug
131  G4cout<<"..G4QPipCS::GetCS:DoNothing,P="<<pMom<<",CS="<<lastCS*millibarn<<G4endl;
132 #endif
133  //CalculateCrossSection(fCS,-1,j,211,lastZ,lastN,pMom); // Update param's only
134  return lastCS*millibarn; // Use theLastCS
135  }
136  in = true; // This is the case when the isotop is found in DB
137  // Momentum pMom is in IU ! @@ Units
138 #ifdef debug
139  G4cout<<"G4QPipCS::G:UpdatDB P="<<pMom<<",f="<<fCS<<",I="<<lastI<<",j="<<j<<G4endl;
140 #endif
141  lastCS=CalculateCrossSection(fCS,-1,j,211,lastZ,lastN,pMom); // read & update
142 #ifdef debug
143  G4cout<<"G4QPipNCS::GetCrosSec: *****> New (inDB) Calculated CS="<<lastCS<<G4endl;
144 #endif
145  if(lastCS<=0. && pMom>lastTH) // Correct the threshold (@@ No intermediate Zeros)
146  {
147 #ifdef debug
148  G4cout<<"G4QPipNCS::GetCS: New P="<<pMom<<"(CS=0) > Threshold="<<lastTH<<G4endl;
149 #endif
150  lastCS=0.;
151  lastTH=pMom;
152  }
153  break; // Go out of the LOOP
154  }
155 #ifdef debug
156  G4cout<<"-->G4QPipNucCrossSec::GetCrosSec: pPDG=211, j="<<j<<", N="<<colN[i]
157  <<",Z["<<i<<"]="<<colZ[i]<<G4endl;
158 #endif
159  j++; // Increment a#0f records found in DB
160  }
161 #ifdef debug
162  G4cout<<"-?-G4QPipCS::GetCS:R,Z="<<tgZ<<",N="<<tgN<<",in="<<in<<",j="<<j<<" ?"<<G4endl;
163 #endif
164  if(!in) // This isotope has not been calculated previously
165  {
166 #ifdef debug
167  G4cout<<"^^^G4QPipCS::GeCS:CalcNew P="<<pMom<<", f="<<fCS<<", lastI="<<lastI<<G4endl;
168 #endif
169  lastCS=CalculateCrossSection(fCS,0,j,211,lastZ,lastN,pMom); //calculate & create
171  //if(lastCS>0.) // It means that the AMBD was initialized
172  //{
173 
174  lastTH = ThresholdEnergy(tgZ, tgN); // The Threshold Energy which is now the last
175 #ifdef debug
176  G4cout<<"G4QPipCrossSection::GetCrossSect:NewThresh="<<lastTH<<",P="<<pMom<<G4endl;
177 #endif
178  colN.push_back(tgN);
179  colZ.push_back(tgZ);
180  colP.push_back(pMom);
181  colTH.push_back(lastTH);
182  colCS.push_back(lastCS);
183 #ifdef debug
184  G4cout<<"G4QPipNCS::GetCrosSec:lCS="<<lastCS<<",lZ="<<lastN<<",lN="<<lastZ<<G4endl;
185 #endif
186  //} // M.K. Presence of H1 with high threshold breaks the syncronization
187 #ifdef pdebug
188  G4cout<<"G4QPipCS::GeCS:1st,P="<<pMom<<"(MeV),CS="<<lastCS*millibarn<<"(mb)"<<G4endl;
189 #endif
190  return lastCS*millibarn;
191  } // End of creation of the new set of parameters
192  else
193  {
194 #ifdef debug
195  G4cout<<"G4QPipNucCS::GetCS: Update lastI="<<lastI<<",j="<<j<<G4endl;
196 #endif
197  colP[lastI]=pMom;
198  colCS[lastI]=lastCS;
199  }
200  } // End of parameters udate
201  else if(pMom<=lastTH)
202  {
203 #ifdef debug
204  G4cout<<"G4QPipCS::GetCS: Current P="<<pMom<<" < Threshold="<<lastTH<<", CS=0"<<G4endl;
205 #endif
206  return 0.; // Momentum is below the Threshold Value -> CS=0
207  }
208  else if(std::fabs(lastP-pMom)<tolerance*pMom)
209  //else if(lastP==pMom) // VI do not use tolerance
210  {
211 #ifdef debug
212  G4cout<<"..G4QPCS::GetCS:OldNZ&P="<<lastP<<"="<<pMom<<",CS="<<lastCS*millibarn<<G4endl;
213 #endif
214  return lastCS*millibarn; // Use theLastCS
215  }
216  else // It is the last used -> use the current tables
217  {
218 #ifdef debug
219  G4cout<<"-!-G4QPCS::GetCS:UseCur P="<<pMom<<",f="<<fCS<<",I="<<lastI<<",j="<<j<<G4endl;
220 #endif
221  lastCS=CalculateCrossSection(fCS,1,j,211,lastZ,lastN,pMom); // Only read and UpdateDB
222  lastP=pMom;
223  }
224 #ifdef debug
225  G4cout<<"==>G4QPipCS::GetCroSec:P="<<pMom<<"(MeV),CS="<<lastCS*millibarn<<"(mb)"<<G4endl;
226 #endif
227  return lastCS*millibarn;
228 }
229 
230 // The main member function giving the gamma-A cross section (E in GeV, CS in mb)
231 G4double G4QPionPlusNuclearCrossSection::CalculateCrossSection(G4bool, G4int F, G4int I,
232  G4int, G4int targZ, G4int targN, G4double Momentum)
233 {
234  static const G4double THmin=27.; // default minimum Momentum (MeV/c) Threshold
235  static const G4double THmiG=THmin*.001; // minimum Momentum (GeV/c) Threshold
236  static const G4double dP=10.; // step for the LEN (Low ENergy) table MeV/c
237  static const G4double dPG=dP*.001; // step for the LEN (Low ENergy) table GeV/c
238  static const G4int nL=105; // A#of LEN points in E (step 10 MeV/c)
239  static const G4double Pmin=THmin+(nL-1)*dP; // minP for the HighE part with safety
240  static const G4double Pmax=227000.; // maxP for the HEN (High ENergy) part 227 GeV
241  static const G4int nH=224; // A#of HEN points in lnE
242  static const G4double milP=std::log(Pmin);// Low logarithm energy for the HEN part
243  static const G4double malP=std::log(Pmax);// High logarithm energy (each 2.75 percent)
244  static const G4double dlP=(malP-milP)/(nH-1); // Step in log energy in the HEN part
245  static const G4double milPG=std::log(.001*Pmin);// Low logarithmEnergy for HEN part GeV/c
246 #ifdef debug
247  G4cout<<"G4QPipNuCS::CalCS:N="<<targN<<",Z="<<targZ<<",P="<<Momentum<<">"<<THmin<<G4endl;
248 #endif
249  G4double sigma=0.;
250  if(F&&I) sigma=0.; // @@ *!* Fake line *!* to use F & I !!!Temporary!!!
251  //G4double A=targN+targZ; // A of the target
252 #ifdef debug
253  G4cout<<"G4QPipNucCS::CalCS: A="<<A<<", F="<<F<<",I="<<I<<",nL="<<nL<<",nH="<<nH<<G4endl;
254 #endif
255  if(F<=0) // This isotope was not the last used isotop
256  {
257  if(F<0) // This isotope was found in DAMDB =-----=> RETRIEVE
258  {
259  G4int sync=LEN->size();
260  if(sync<=I) G4cerr<<"*!*G4QPiMinusNuclCS::CalcCrosSect:Sync="<<sync<<"<="<<I<<G4endl;
261  lastLEN=(*LEN)[I]; // Pointer to prepared LowEnergy cross sections
262  lastHEN=(*HEN)[I]; // Pointer to prepared High Energy cross sections
263  }
264  else // This isotope wasn't calculated before => CREATE
265  {
266  lastLEN = new G4double[nL]; // Allocate memory for the new LEN cross sections
267  lastHEN = new G4double[nH]; // Allocate memory for the new HEN cross sections
268  // --- Instead of making a separate function ---
269  G4double P=THmiG; // Table threshold in GeV/c
270  for(G4int n=0; n<nL; n++)
271  {
272  lastLEN[n] = CrossSectionLin(targZ, targN, P);
273  P+=dPG;
274  }
275  G4double lP=milPG;
276  for(G4int n=0; n<nH; n++)
277  {
278  lastHEN[n] = CrossSectionLog(targZ, targN, lP);
279  lP+=dlP;
280  }
281 #ifdef debug
282  G4cout<<"-*->G4QPipNucCS::CalcCS:Tab for Z="<<targZ<<", N="<<targN<<",I="<<I<<G4endl;
283 #endif
284  // --- End of possible separate function
285  // *** The synchronization check ***
286  G4int sync=LEN->size();
287  if(sync!=I)
288  {
289  G4cerr<<"***G4QPiMinusNuclCS::CalcCrossSect: Sinc="<<sync<<"#"<<I<<", Z=" <<targZ
290  <<", N="<<targN<<", F="<<F<<G4endl;
291  //G4Exception("G4PiMinusNuclearCS::CalculateCS:","39",FatalException,"DBoverflow");
292  }
293  LEN->push_back(lastLEN); // remember the Low Energy Table
294  HEN->push_back(lastHEN); // remember the High Energy Table
295  } // End of creation of the new set of parameters
296  } // End of parameters udate
297  // =-----------------= NOW the Magic Formula =-------------------------=
298 #ifdef debug
299  G4cout<<"G4QPipNCS::CalcCS:lTH="<<lastTH<<",Pi="<<Pmin<<",dP="<<dP<<",dlP="<<dlP<<G4endl;
300 #endif
301  if (Momentum<lastTH) return 0.; // It must be already checked in the interface class
302  else if (Momentum<Pmin) // High Energy region
303  {
304 #ifdef debug
305  G4cout<<"G4QPipNCS::CalcCS:bLEN nL="<<nL<<",TH="<<THmin<<",dP="<<dP<<G4endl;
306 #endif
307  sigma=EquLinearFit(Momentum,nL,THmin,dP,lastLEN);
308 #ifdef debugn
309  if(sigma<0.)
310  G4cout<<"G4QPipNuCS::CalCS: E="<<Momentum<<",T="<<THmin<<",dP="<<dP<<G4endl;
311 #endif
312  }
313  else if (Momentum<Pmax) // High Energy region
314  {
315  G4double lP=std::log(Momentum);
316 #ifdef debug
317  G4cout<<"G4QPipNucCS::CalcCS: before HEN nH="<<nH<<", iE="<<milP<<",dlP="<<dlP<<G4endl;
318 #endif
319  sigma=EquLinearFit(lP,nH,milP,dlP,lastHEN);
320  }
321  else // UHE region (calculation, not frequent)
322  {
323  G4double P=0.001*Momentum; // Approximation formula is for P in GeV/c
324  sigma=CrossSectionFormula(targZ, targN, P, std::log(P));
325  }
326 #ifdef debug
327  G4cout<<"G4QPionPlusNuclearCrossSection::CalcCS: CS="<<sigma<<G4endl;
328 #endif
329  if(sigma<0.) return 0.;
330  return sigma;
331 }
332 
333 // Electromagnetic momentum-threshold (in MeV/c)
334 G4double G4QPionPlusNuclearCrossSection::ThresholdMomentum(G4int tZ, G4int tN)
335 {
336  static const G4double third=1./3.;
337  static const G4double pM = G4QPDGCode(211).GetMass(); // Projectile mass in MeV
338  static const G4double tpM= pM+pM; // Doubled projectile mass (MeV)
339  G4double tA=tZ+tN;
340  if(tZ<.99 || tN<0.) return 0.;
341  else if(tZ==1 && tN==0) return 300.; // A threshold on the free proton
342  //G4double dE=1.263*tZ/(1.+std::pow(tA,third));
343  G4double dE=tZ/(1.+std::pow(tA,third)); // Safety for diffused edge of the nucleus (QE)
344  G4double tM=931.5*tA;
345  G4double T=dE+dE*(dE/2+pM)/tM;
346  return std::sqrt(T*(tpM+T));
347 }
348 
349 // Calculation formula for piMinus-nuclear inelastic cross-section (mb) (P in GeV/c)
350 G4double G4QPionPlusNuclearCrossSection::CrossSectionLin(G4int tZ, G4int tN, G4double P)
351 {
352  G4double lP=std::log(P);
353  return CrossSectionFormula(tZ, tN, P, lP);
354 }
355 
356 // Calculation formula for piMinus-nuclear inelastic cross-section (mb) log(P in GeV/c)
357 G4double G4QPionPlusNuclearCrossSection::CrossSectionLog(G4int tZ, G4int tN, G4double lP)
358 {
359  G4double P=std::exp(lP);
360  return CrossSectionFormula(tZ, tN, P, lP);
361 }
362 // Calculation formula for piMinus-nuclear inelastic cross-section (mb) log(P in GeV/c)
363 G4double G4QPionPlusNuclearCrossSection::CrossSectionFormula(G4int tZ, G4int tN,
364  G4double P, G4double lP)
365 {
366  G4double sigma=0.;
367  if(tZ==1 && !tN) // PiPlus-Proton interaction from G4QuasiElRatios
368  {
369  G4double ld=lP-3.5;
370  G4double ld2=ld*ld;
371  G4double p2=P*P;
372  G4double p4=p2*p2;
373  G4double sp=std::sqrt(P);
374  G4double lm=lP-.32;
375  G4double md=lm*lm+.04;
376  G4double El=(.0557*ld2+2.4+6./sp)/(1.+3./p4);
377  G4double To=(.3*ld2+22.3+5./sp)/(1.+1./p4);
378  sigma=(To-El)+.1/md;
379  }
380  else if(tZ==1 && tN==1) // pimp_tot
381  {
382  G4double p2=P*P;
383  G4double d=lP-2.7;
384  G4double f=lP+1.25;
385  G4double g_value=lP-.017;
386  sigma=(.55*d*d+38.+23./std::sqrt(P))/(1.+.3/p2/p2)+18./(f*f+.1089)+.02/(g_value*g_value+.0025);
387  }
388  else if(tZ<97 && tN<152) // General solution
389  {
390  G4double d=lP-4.2;
391  G4double p2=P*P;
392  G4double p4=p2*p2;
393  G4double a=tN+tZ; // A of the target
394  G4double al=std::log(a);
395  G4double sa=std::sqrt(a);
396  G4double ssa=std::sqrt(sa);
397  G4double a2=a*a;
398  G4double c=41.*std::exp(al*.68)*(1.+44./a2)/(1.+8./a)/(1.+200./a2/a2);
399  G4double f=290.*ssa/(1.+34./a/ssa);
400  G4double g_value=-1.32-al*.043;
401  G4double u=lP-g_value;
402  G4double h=al*(.4-.055*al);
403  G4double r=.01+a2*5.E-8;
404  sigma=(c+d*d)/(1.+(.2-.009*sa)/p4)+f/(u*u+h*h)/(1.+r/p2);
405 #ifdef pdebug
406  G4cout<<"G4QPiPlusNucCS::CSForm: A="<<a<<",P="<<P<<",CS="<<sigma<<",c="<<c<<",g="<<g_value
407  <<",d="<<d<<",r="<<r<<",e="<<e<<",h="<<h<<G4endl;
408 #endif
409  }
410  else
411  {
412  G4cerr<<"-Warning-G4QPiPlusNuclearCroSect::CSForm:*Bad A* Z="<<tZ<<", N="<<tN<<G4endl;
413  sigma=0.;
414  }
415  if(sigma<0.) return 0.;
416  return sigma;
417 }
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