source: trunk/source/processes/hadronic/cross_sections/src/G4GGNuclNuclCrossSection.cc@ 1315

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15// * use. Please see the license in the file LICENSE and URL above *
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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 *
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24// ********************************************************************
25//
26//
27// 24.11.08 V. Grichine - first implementation
28//
29
30#include "G4GGNuclNuclCrossSection.hh"
31
32#include "G4ParticleTable.hh"
33#include "G4IonTable.hh"
34#include "G4ParticleDefinition.hh"
35
36
37
38////////////////////////////////////////////////////////////////////////////////
39//
40//
41
42G4GGNuclNuclCrossSection::G4GGNuclNuclCrossSection()
43: fUpperLimit( 100000 * GeV ),
44 fLowerLimit( 0.1 * MeV ),
45 fRadiusConst( 1.08*fermi ) // 1.1, 1.3 ?
46{
47 theProton = G4Proton::Proton();
48 theNeutron = G4Neutron::Neutron();
49}
50
51///////////////////////////////////////////////////////////////////////////////////////
52//
53//
54
55G4GGNuclNuclCrossSection::~G4GGNuclNuclCrossSection()
56{
57}
58
59
60////////////////////////////////////////////////////////////////////////////////////////
61//
62//
63
64
65G4bool
66G4GGNuclNuclCrossSection::IsApplicable(const G4DynamicParticle* aDP,
67 const G4Element* anElement)
68{
69 return IsZAApplicable(aDP, anElement->GetZ(), anElement->GetN());
70}
71
72////////////////////////////////////////////////////////////////////////////////////////
73//
74//
75
76G4bool
77G4GGNuclNuclCrossSection::IsZAApplicable(const G4DynamicParticle* aDP,
78 G4double Z, G4double)
79{
80 G4bool applicable = false;
81 // G4int baryonNumber = aDP->GetDefinition()->GetBaryonNumber();
82 G4double kineticEnergy = aDP->GetKineticEnergy();
83
84 // const G4ParticleDefinition* theParticle = aDP->GetDefinition();
85
86 if ( kineticEnergy >= fLowerLimit && Z > 1.5 ) applicable = true;
87
88 return applicable;
89}
90
91////////////////////////////////////////////////////////////////////////////////////////
92//
93// Calculates total and inelastic Xsc, derives elastic as total - inelastic accordong to
94// Glauber model with Gribov correction calculated in the dipole approximation on
95// light cone. Gaussian density helps to calculate rest integrals of the model.
96// [1] B.Z. Kopeliovich, nucl-th/0306044
97
98
99G4double G4GGNuclNuclCrossSection::
100GetCrossSection(const G4DynamicParticle* aParticle, const G4Element* anElement, G4double T)
101{
102 return GetIsoZACrossSection(aParticle, anElement->GetZ(), anElement->GetN(), T);
103}
104
105////////////////////////////////////////////////////////////////////////////////////////
106//
107// Calculates total and inelastic Xsc, derives elastic as total - inelastic accordong to
108// Glauber model with Gribov correction calculated in the dipole approximation on
109// light cone. Gaussian density of point-like nucleons helps to calculate rest integrals of the model.
110// [1] B.Z. Kopeliovich, nucl-th/0306044 + simplification above
111
112
113
114G4double G4GGNuclNuclCrossSection::
115GetIsoZACrossSection(const G4DynamicParticle* aParticle, G4double tZ, G4double tA, G4double)
116{
117 G4double xsection, sigma, cofInelastic = 2.4, cofTotal = 2.0, nucleusSquare, cB, ratio;
118
119 G4double pZ = aParticle->GetDefinition()->GetPDGCharge();
120 G4double pA = aParticle->GetDefinition()->GetBaryonNumber();
121
122 G4double pTkin = aParticle->GetKineticEnergy();
123 pTkin /= pA;
124
125 G4double pN = pA - pZ;
126 if( pN < 0. ) pN = 0.;
127
128 G4double tN = tA - tZ;
129 if( tN < 0. ) tN = 0.;
130
131 G4double tR = GetNucleusRadius(tA);
132 G4double pR = GetNucleusRadius(pA);
133
134 cB = GetCoulombBarier(aParticle, tZ, tA, pR, tR);
135
136 if(cB > 0.)
137 {
138
139 sigma = (pZ*tZ+pN*tN)*GetHadronNucleonXscNS(theProton, pTkin, theProton) +
140 (pZ*tN+pN*tZ)*GetHadronNucleonXscNS(theProton, pTkin, theNeutron);
141
142 nucleusSquare = cofTotal*pi*( pR*pR + tR*tR ); // basically 2piRR
143
144 ratio = sigma/nucleusSquare;
145
146 xsection = nucleusSquare*std::log( 1. + ratio );
147
148 fTotalXsc = xsection;
149
150 fTotalXsc *= cB;
151
152 fInelasticXsc = nucleusSquare*std::log( 1. + cofInelastic*ratio )/cofInelastic;
153
154 fInelasticXsc *= cB;
155
156 fElasticXsc = fTotalXsc - fInelasticXsc;
157
158 // if (fElasticXsc < DBL_MIN) fElasticXsc = DBL_MIN;
159 /*
160 G4double difratio = ratio/(1.+ratio);
161
162 fDiffractionXsc = 0.5*nucleusSquare*( difratio - std::log( 1. + difratio ) );
163 */
164 // production to be checked !!! edit MK xsc
165
166 //sigma = (pZ*tZ+pN*tN)*GetHadronNucleonXscMK(theProton, pTkin, theProton) +
167 // (pZ*tN+pN*tZ)*GetHadronNucleonXscMK(theProton, pTkin, theNeutron);
168
169 sigma = (pZ*tZ+pN*tN)*GetHadronNucleonXscNS(theProton, pTkin, theProton) +
170 (pZ*tN+pN*tZ)*GetHadronNucleonXscNS(theProton, pTkin, theNeutron);
171
172 ratio = sigma/nucleusSquare;
173
174 fProductionXsc = nucleusSquare*std::log( 1. + cofInelastic*ratio )/cofInelastic;
175
176 if (fElasticXsc < 0.) fElasticXsc = 0.;
177 }
178 else
179 {
180 fInelasticXsc = 0.;
181 fTotalXsc = 0.;
182 fElasticXsc = 0.;
183 fProductionXsc = 0.;
184 }
185 return fInelasticXsc; // xsection;
186}
187
188////////////////////////////////////////////////////////////////////////////////////////
189//
190//
191
192G4double G4GGNuclNuclCrossSection::
193GetCoulombBarier(const G4DynamicParticle* aParticle, G4double tZ, G4double tA, G4double pR, G4double tR)
194{
195 G4double ratio;
196 G4double pZ = aParticle->GetDefinition()->GetPDGCharge();
197
198
199 G4double pTkin = aParticle->GetKineticEnergy();
200 // G4double pPlab = aParticle->GetTotalMomentum();
201 G4double pM = aParticle->GetDefinition()->GetPDGMass();
202 // G4double tM = tZ*proton_mass_c2 + (tA-tZ)*neutron_mass_c2; // ~ 1% accuracy
203 G4double tM = G4ParticleTable::GetParticleTable()->GetIonTable()->GetIonMass( G4int(tZ), G4int(tA) );
204 G4double pElab = pTkin + pM;
205 G4double totEcm = std::sqrt(pM*pM + tM*tM + 2.*pElab*tM);
206 // G4double pPcm = pPlab*tM/totEcm;
207 // G4double pTcm = std::sqrt(pM*pM + pPcm*pPcm) - pM;
208 G4double totTcm = totEcm - pM -tM;
209
210 G4double bC = fine_structure_const*hbarc*pZ*tZ;
211 bC /= pR + tR;
212 bC /= 2.; // 4., 2. parametrisation cof ??? vmg
213
214 // G4cout<<"pTkin = "<<pTkin/GeV<<"; pPlab = "
215 // <<pPlab/GeV<<"; bC = "<<bC/GeV<<"; pTcm = "<<pTcm/GeV<<G4endl;
216
217 if( totTcm <= bC ) ratio = 0.;
218 else ratio = 1. - bC/totTcm;
219
220 // if(ratio < DBL_MIN) ratio = DBL_MIN;
221 if( ratio < 0.) ratio = 0.;
222
223 // G4cout <<"ratio = "<<ratio<<G4endl;
224 return ratio;
225}
226
227
228//////////////////////////////////////////////////////////////////////////
229//
230// Return single-diffraction/inelastic cross-section ratio
231
232G4double G4GGNuclNuclCrossSection::
233GetRatioSD(const G4DynamicParticle* aParticle, G4double tA, G4double tZ)
234{
235 G4double sigma, cofInelastic = 2.4, cofTotal = 2.0, nucleusSquare, ratio;
236
237 G4double pZ = aParticle->GetDefinition()->GetPDGCharge();
238 G4double pA = aParticle->GetDefinition()->GetBaryonNumber();
239
240 G4double pTkin = aParticle->GetKineticEnergy();
241 pTkin /= pA;
242
243 G4double pN = pA - pZ;
244 if( pN < 0. ) pN = 0.;
245
246 G4double tN = tA - tZ;
247 if( tN < 0. ) tN = 0.;
248
249 G4double tR = GetNucleusRadius(tA);
250 G4double pR = GetNucleusRadius(pA);
251
252 sigma = (pZ*tZ+pN*tN)*GetHadronNucleonXscNS(theProton, pTkin, theProton) +
253 (pZ*tN+pN*tZ)*GetHadronNucleonXscNS(theProton, pTkin, theNeutron);
254
255 nucleusSquare = cofTotal*pi*( pR*pR + tR*tR ); // basically 2piRR
256
257 ratio = sigma/nucleusSquare;
258
259
260 fInelasticXsc = nucleusSquare*std::log( 1. + cofInelastic*ratio )/cofInelastic;
261
262 G4double difratio = ratio/(1.+ratio);
263
264 fDiffractionXsc = 0.5*nucleusSquare*( difratio - std::log( 1. + difratio ) );
265
266 if (fInelasticXsc > 0.) ratio = fDiffractionXsc/fInelasticXsc;
267 else ratio = 0.;
268
269 return ratio;
270}
271
272//////////////////////////////////////////////////////////////////////////
273//
274// Return suasi-elastic/inelastic cross-section ratio
275
276G4double G4GGNuclNuclCrossSection::
277GetRatioQE(const G4DynamicParticle* aParticle, G4double tA, G4double tZ)
278{
279 G4double sigma, cofInelastic = 2.4, cofTotal = 2.0, nucleusSquare, ratio;
280
281 G4double pZ = aParticle->GetDefinition()->GetPDGCharge();
282 G4double pA = aParticle->GetDefinition()->GetBaryonNumber();
283
284 G4double pTkin = aParticle->GetKineticEnergy();
285 pTkin /= pA;
286
287 G4double pN = pA - pZ;
288 if( pN < 0. ) pN = 0.;
289
290 G4double tN = tA - tZ;
291 if( tN < 0. ) tN = 0.;
292
293 G4double tR = GetNucleusRadius(tA);
294 G4double pR = GetNucleusRadius(pA);
295
296 sigma = (pZ*tZ+pN*tN)*GetHadronNucleonXscNS(theProton, pTkin, theProton) +
297 (pZ*tN+pN*tZ)*GetHadronNucleonXscNS(theProton, pTkin, theNeutron);
298
299 nucleusSquare = cofTotal*pi*( pR*pR + tR*tR ); // basically 2piRR
300
301 ratio = sigma/nucleusSquare;
302
303 fInelasticXsc = nucleusSquare*std::log( 1. + cofInelastic*ratio )/cofInelastic;
304
305 // sigma = GetHNinelasticXsc(aParticle, tA, tZ);
306 ratio = sigma/nucleusSquare;
307
308 fProductionXsc = nucleusSquare*std::log( 1. + cofInelastic*ratio )/cofInelastic;
309
310 if (fInelasticXsc > fProductionXsc) ratio = (fInelasticXsc-fProductionXsc)/fInelasticXsc;
311 else ratio = 0.;
312 if ( ratio < 0. ) ratio = 0.;
313
314 return ratio;
315}
316
317/////////////////////////////////////////////////////////////////////////////////////
318//
319// Returns hadron-nucleon Xsc according to differnt parametrisations:
320// [2] E. Levin, hep-ph/9710546
321// [3] U. Dersch, et al, hep-ex/9910052
322// [4] M.J. Longo, et al, Phys.Rev.Lett. 33 (1974) 725
323
324G4double
325G4GGNuclNuclCrossSection::GetHadronNucleonXsc(const G4DynamicParticle* aParticle,
326 const G4Element* anElement )
327{
328 G4double At = anElement->GetN(); // number of nucleons
329 G4double Zt = anElement->GetZ(); // number of protons
330
331
332 return GetHadronNucleonXsc( aParticle, At, Zt );
333}
334
335
336
337
338/////////////////////////////////////////////////////////////////////////////////////
339//
340// Returns hadron-nucleon Xsc according to differnt parametrisations:
341// [2] E. Levin, hep-ph/9710546
342// [3] U. Dersch, et al, hep-ex/9910052
343// [4] M.J. Longo, et al, Phys.Rev.Lett. 33 (1974) 725
344
345G4double
346G4GGNuclNuclCrossSection::GetHadronNucleonXsc(const G4DynamicParticle* aParticle,
347 G4double At, G4double Zt )
348{
349 G4double xsection = 0.;
350
351
352 G4double targ_mass = G4ParticleTable::GetParticleTable()->
353 GetIonTable()->GetIonMass( G4int(Zt+0.5) , G4int(At+0.5) );
354
355 targ_mass = 0.939*GeV; // ~mean neutron and proton ???
356
357 G4double proj_mass = aParticle->GetMass();
358 G4double proj_momentum = aParticle->GetMomentum().mag();
359 G4double sMand = CalcMandelstamS ( proj_mass , targ_mass , proj_momentum );
360
361 sMand /= GeV*GeV; // in GeV for parametrisation
362 proj_momentum /= GeV;
363
364 const G4ParticleDefinition* pParticle = aParticle->GetDefinition();
365
366
367 if(pParticle == theNeutron) // as proton ???
368 {
369 xsection = At*(21.70*std::pow(sMand,0.0808) + 56.08*std::pow(sMand,-0.4525));
370 }
371 else if(pParticle == theProton)
372 {
373 xsection = At*(21.70*std::pow(sMand,0.0808) + 56.08*std::pow(sMand,-0.4525));
374 // xsection = At*( 49.51*std::pow(sMand,-0.097) + 0.314*std::log(sMand)*std::log(sMand) );
375 // xsection = At*( 38.4 + 0.85*std::abs(std::pow(log(sMand),1.47)) );
376 }
377
378 xsection *= millibarn;
379 return xsection;
380}
381
382
383/////////////////////////////////////////////////////////////////////////////////////
384//
385// Returns hadron-nucleon Xsc according to PDG parametrisation (2005):
386// http://pdg.lbl.gov/2006/reviews/hadronicrpp.pdf
387
388G4double
389G4GGNuclNuclCrossSection::GetHadronNucleonXscPDG(const G4DynamicParticle* aParticle,
390 const G4Element* anElement )
391{
392 G4double At = anElement->GetN(); // number of nucleons
393 G4double Zt = anElement->GetZ(); // number of protons
394
395
396 return GetHadronNucleonXscPDG( aParticle, At, Zt );
397}
398
399
400
401
402/////////////////////////////////////////////////////////////////////////////////////
403//
404// Returns hadron-nucleon Xsc according to PDG parametrisation (2005):
405// http://pdg.lbl.gov/2006/reviews/hadronicrpp.pdf
406// At = number of nucleons, Zt = number of protons
407
408G4double
409G4GGNuclNuclCrossSection::GetHadronNucleonXscPDG(const G4DynamicParticle* aParticle,
410 G4double At, G4double Zt )
411{
412 G4double xsection = 0.;
413
414 G4double Nt = At-Zt; // number of neutrons
415 if (Nt < 0.) Nt = 0.;
416
417
418 G4double targ_mass = G4ParticleTable::GetParticleTable()->
419 GetIonTable()->GetIonMass( G4int(Zt+0.5) , G4int(At+0.5) );
420
421 targ_mass = 0.939*GeV; // ~mean neutron and proton ???
422
423 G4double proj_mass = aParticle->GetMass();
424 G4double proj_momentum = aParticle->GetMomentum().mag();
425
426 G4double sMand = CalcMandelstamS ( proj_mass , targ_mass , proj_momentum );
427
428 sMand /= GeV*GeV; // in GeV for parametrisation
429
430 // General PDG fit constants
431
432 G4double s0 = 5.38*5.38; // in Gev^2
433 G4double eta1 = 0.458;
434 G4double eta2 = 0.458;
435 G4double B = 0.308;
436
437
438 const G4ParticleDefinition* pParticle = aParticle->GetDefinition();
439
440
441 if(pParticle == theNeutron) // proton-neutron fit
442 {
443 xsection = Zt*( 35.80 + B*std::pow(std::log(sMand/s0),2.)
444 + 40.15*std::pow(sMand,-eta1) - 30.*std::pow(sMand,-eta2));
445 xsection += Nt*( 35.45 + B*std::pow(std::log(sMand/s0),2.)
446 + 42.53*std::pow(sMand,-eta1) - 33.34*std::pow(sMand,-eta2)); // pp for nn
447 }
448 else if(pParticle == theProton)
449 {
450
451 xsection = Zt*( 35.45 + B*std::pow(std::log(sMand/s0),2.)
452 + 42.53*std::pow(sMand,-eta1) - 33.34*std::pow(sMand,-eta2));
453
454 xsection += Nt*( 35.80 + B*std::pow(std::log(sMand/s0),2.)
455 + 40.15*std::pow(sMand,-eta1) - 30.*std::pow(sMand,-eta2));
456 }
457 xsection *= millibarn; // parametrised in mb
458 return xsection;
459}
460
461
462
463
464/////////////////////////////////////////////////////////////////////////////////////
465//
466// Returns nucleon-nucleon cross-section based on N. Starkov parametrisation of
467// data from mainly http://wwwppds.ihep.su:8001/c5-6A.html database
468// projectile nucleon is pParticle with pTkin shooting target nucleon tParticle
469
470G4double
471G4GGNuclNuclCrossSection::GetHadronNucleonXscNS( G4ParticleDefinition* pParticle,
472 G4double pTkin,
473 G4ParticleDefinition* tParticle)
474{
475 G4double xsection(0), Delta, A0, B0;
476 G4double hpXsc(0);
477 G4double hnXsc(0);
478
479
480 G4double targ_mass = tParticle->GetPDGMass();
481 G4double proj_mass = pParticle->GetPDGMass();
482
483 G4double proj_energy = proj_mass + pTkin;
484 G4double proj_momentum = std::sqrt(pTkin*(pTkin+2*proj_mass));
485
486 G4double sMand = CalcMandelstamS ( proj_mass , targ_mass , proj_momentum );
487
488 sMand /= GeV*GeV; // in GeV for parametrisation
489 proj_momentum /= GeV;
490 proj_energy /= GeV;
491 proj_mass /= GeV;
492
493 // General PDG fit constants
494
495 // G4double s0 = 5.38*5.38; // in Gev^2
496 // G4double eta1 = 0.458;
497 // G4double eta2 = 0.458;
498 // G4double B = 0.308;
499
500
501
502
503
504 if( proj_momentum >= 10. ) // high energy: pp = nn = np
505 // if( proj_momentum >= 2.)
506 {
507 Delta = 1.;
508
509 if( proj_energy < 40. ) Delta = 0.916+0.0021*proj_energy;
510
511 if( proj_momentum >= 10.)
512 {
513 B0 = 7.5;
514 A0 = 100. - B0*std::log(3.0e7);
515
516 xsection = A0 + B0*std::log(proj_energy) - 11
517 + 103*std::pow(2*0.93827*proj_energy + proj_mass*proj_mass+
518 0.93827*0.93827,-0.165); // mb
519 }
520 }
521 else // low energy pp = nn != np
522 {
523 if(pParticle == tParticle) // pp or nn // nn to be pp
524 {
525 if( proj_momentum < 0.73 )
526 {
527 hnXsc = 23 + 50*( std::pow( std::log(0.73/proj_momentum), 3.5 ) );
528 }
529 else if( proj_momentum < 1.05 )
530 {
531 hnXsc = 23 + 40*(std::log(proj_momentum/0.73))*
532 (std::log(proj_momentum/0.73));
533 }
534 else // if( proj_momentum < 10. )
535 {
536 hnXsc = 39.0 +
537 75*(proj_momentum - 1.2)/(std::pow(proj_momentum,3.0) + 0.15);
538 }
539 xsection = hnXsc;
540 }
541 else // pn to be np
542 {
543 if( proj_momentum < 0.8 )
544 {
545 hpXsc = 33+30*std::pow(std::log(proj_momentum/1.3),4.0);
546 }
547 else if( proj_momentum < 1.4 )
548 {
549 hpXsc = 33+30*std::pow(std::log(proj_momentum/0.95),2.0);
550 }
551 else // if( proj_momentum < 10. )
552 {
553 hpXsc = 33.3+
554 20.8*(std::pow(proj_momentum,2.0)-1.35)/
555 (std::pow(proj_momentum,2.50)+0.95);
556 }
557 xsection = hpXsc;
558 }
559 }
560 xsection *= millibarn; // parametrised in mb
561 return xsection;
562}
563
564/*
565/////////////////////////////////////////////////////////////////////////////////////
566//
567// Returns hadron-nucleon inelastic cross-section based on proper parametrisation
568
569G4double
570G4GGNuclNuclCrossSection::GetHNinelasticXsc(const G4DynamicParticle* aParticle,
571 const G4Element* anElement )
572{
573 G4double At = anElement->GetN(); // number of nucleons
574 G4double Zt = anElement->GetZ(); // number of protons
575
576
577 return GetHNinelasticXsc( aParticle, At, Zt );
578}
579
580/////////////////////////////////////////////////////////////////////////////////////
581//
582// Returns hadron-nucleon inelastic cross-section based on FTF-parametrisation
583
584G4double
585G4GGNuclNuclCrossSection::GetHNinelasticXsc(const G4DynamicParticle* aParticle,
586 G4double At, G4double Zt )
587{
588 // G4ParticleDefinition* hadron = aParticle->GetDefinition();
589 G4double sumInelastic, Nt = At - Zt;
590
591 if(Nt < 0.) Nt = 0.;
592
593 sumInelastic = Zt*GetHadronNucleonXscNS(aParticle, theProton);
594 sumInelastic += Nt*GetHadronNucleonXscNS(aParticle, theNeutron);
595
596 return sumInelastic;
597}
598*/
599
600/////////////////////////////////////////////////////////////////////////////////////
601//
602// Returns hadron-nucleon inelastic cross-section based on FTF-parametrisation
603
604G4double
605G4GGNuclNuclCrossSection::GetHNinelasticXscVU(const G4DynamicParticle* aParticle,
606 G4double At, G4double Zt )
607{
608 G4int PDGcode = aParticle->GetDefinition()->GetPDGEncoding();
609 G4int absPDGcode = std::abs(PDGcode);
610
611 G4double Elab = aParticle->GetTotalEnergy();
612 // (s - 2*0.88*GeV*GeV)/(2*0.939*GeV)/GeV;
613 G4double Plab = aParticle->GetMomentum().mag();
614 // std::sqrt(Elab * Elab - 0.88);
615
616 Elab /= GeV;
617 Plab /= GeV;
618
619 G4double LogPlab = std::log( Plab );
620 G4double sqrLogPlab = LogPlab * LogPlab;
621
622 //G4cout<<"Plab = "<<Plab<<G4endl;
623
624 G4double NumberOfTargetProtons = Zt;
625 G4double NumberOfTargetNucleons = At;
626 G4double NumberOfTargetNeutrons = NumberOfTargetNucleons - NumberOfTargetProtons;
627
628 if(NumberOfTargetNeutrons < 0.) NumberOfTargetNeutrons = 0.;
629
630 G4double Xtotal = 0., Xelastic = 0., Xinelastic =0.;
631
632 if( absPDGcode > 1000 ) //------Projectile is baryon --------
633 {
634 G4double XtotPP = 48.0 + 0. *std::pow(Plab, 0. ) +
635 0.522*sqrLogPlab - 4.51*LogPlab;
636
637 G4double XtotPN = 47.3 + 0. *std::pow(Plab, 0. ) +
638 0.513*sqrLogPlab - 4.27*LogPlab;
639
640 G4double XelPP = 11.9 + 26.9*std::pow(Plab,-1.21) +
641 0.169*sqrLogPlab - 1.85*LogPlab;
642
643 G4double XelPN = 11.9 + 26.9*std::pow(Plab,-1.21) +
644 0.169*sqrLogPlab - 1.85*LogPlab;
645
646 Xtotal = ( NumberOfTargetProtons * XtotPP +
647 NumberOfTargetNeutrons * XtotPN );
648
649 Xelastic = ( NumberOfTargetProtons * XelPP +
650 NumberOfTargetNeutrons * XelPN );
651 }
652 Xinelastic = Xtotal - Xelastic;
653
654 if(Xinelastic < 0.) Xinelastic = 0.;
655
656 return Xinelastic*= millibarn;
657}
658
659////////////////////////////////////////////////////////////////////////////////////
660//
661//
662
663G4double
664G4GGNuclNuclCrossSection::GetNucleusRadius( const G4DynamicParticle* ,
665 const G4Element* anElement)
666{
667 G4double At = anElement->GetN();
668 G4double oneThird = 1.0/3.0;
669 G4double cubicrAt = std::pow (At, oneThird);
670
671
672 G4double R; // = fRadiusConst*cubicrAt;
673 /*
674 G4double tmp = std::pow( cubicrAt-1., 3.);
675 tmp += At;
676 tmp *= 0.5;
677
678 if (At > 20.) // 20.
679 {
680 R = fRadiusConst*std::pow (tmp, oneThird);
681 }
682 else
683 {
684 R = fRadiusConst*cubicrAt;
685 }
686 */
687
688 R = fRadiusConst*cubicrAt;
689
690 // return R; // !!!!
691
692
693
694 G4double meanA = 21.;
695
696 G4double tauA1 = 40.;
697 G4double tauA2 = 10.;
698 G4double tauA3 = 5.;
699
700 G4double a1 = 0.85;
701 G4double b1 = 1. - a1;
702
703 G4double b2 = 0.3;
704 G4double b3 = 4.;
705
706 if (At > 20.) // 20.
707 {
708 R *= ( a1 + b1*std::exp( -(At - meanA)/tauA1) );
709 }
710 else if (At > 3.5)
711 {
712 R *= ( 1.0 + b2*( 1. - std::exp( (At - meanA)/tauA2) ) );
713 }
714 else
715 {
716 R *= ( 1.0 + b3*( 1. - std::exp( (At - meanA)/tauA3) ) );
717 }
718 return R;
719
720}
721
722////////////////////////////////////////////////////////////////////////////////////
723//
724//
725
726G4double
727G4GGNuclNuclCrossSection::GetNucleusRadius(G4double At)
728{
729 G4double R;
730
731 // R = GetNucleusRadiusGG(At);
732
733 R = GetNucleusRadiusDE(At);
734
735 return R;
736}
737
738///////////////////////////////////////////////////////////////////
739
740G4double
741G4GGNuclNuclCrossSection::GetNucleusRadiusGG(G4double At)
742{
743
744 G4double oneThird = 1.0/3.0;
745 G4double cubicrAt = std::pow (At, oneThird);
746
747
748 G4double R; // = fRadiusConst*cubicrAt;
749
750 /*
751 G4double tmp = std::pow( cubicrAt-1., 3.);
752 tmp += At;
753 tmp *= 0.5;
754
755 if (At > 20.)
756 {
757 R = fRadiusConst*std::pow (tmp, oneThird);
758 }
759 else
760 {
761 R = fRadiusConst*cubicrAt;
762 }
763 */
764
765 R = fRadiusConst*cubicrAt;
766
767 G4double meanA = 20.;
768 G4double tauA = 20.;
769
770 if ( At > 20.) // 20.
771 {
772 R *= ( 0.8 + 0.2*std::exp( -(At - meanA)/tauA) );
773 }
774 else
775 {
776 R *= ( 1.0 + 0.1*( 1. - std::exp( (At - meanA)/tauA) ) );
777 }
778
779 return R;
780
781}
782
783
784G4double
785G4GGNuclNuclCrossSection::GetNucleusRadiusDE(G4double A)
786{
787
788 // algorithm from diffuse-elastic
789
790 G4double R, r0, a11, a12, a13, a2, a3;
791
792 a11 = 1.26; // 1.08, 1.16
793 a12 = 1.; // 1.08, 1.16
794 a13 = 1.12; // 1.08, 1.16
795 a2 = 1.1;
796 a3 = 1.;
797
798
799 if( A < 50. )
800 {
801 if( 10 < A && A <= 15. ) r0 = a11*( 1 - std::pow(A, -2./3.) )*fermi; // 1.08*fermi;
802 else if( 15 < A && A <= 20 ) r0 = a12*( 1 - std::pow(A, -2./3.) )*fermi;
803 else if( 20 < A && A <= 30 ) r0 = a13*( 1 - std::pow(A, -2./3.) )*fermi;
804 else r0 = a2*fermi;
805
806 R = r0*std::pow( A, 1./3. );
807 }
808 else
809 {
810 r0 = a3*fermi;
811
812 R = r0*std::pow(A, 0.27);
813 }
814 return R;
815}
816
817
818////////////////////////////////////////////////////////////////////////////////////
819//
820//
821
822G4double G4GGNuclNuclCrossSection::CalculateEcmValue( const G4double mp ,
823 const G4double mt ,
824 const G4double Plab )
825{
826 G4double Elab = std::sqrt ( mp * mp + Plab * Plab );
827 G4double Ecm = std::sqrt ( mp * mp + mt * mt + 2 * Elab * mt );
828 // G4double Pcm = Plab * mt / Ecm;
829 // G4double KEcm = std::sqrt ( Pcm * Pcm + mp * mp ) - mp;
830
831 return Ecm ; // KEcm;
832}
833
834
835////////////////////////////////////////////////////////////////////////////////////
836//
837//
838
839G4double G4GGNuclNuclCrossSection::CalcMandelstamS( const G4double mp ,
840 const G4double mt ,
841 const G4double Plab )
842{
843 G4double Elab = std::sqrt ( mp * mp + Plab * Plab );
844 G4double sMand = mp*mp + mt*mt + 2*Elab*mt ;
845
846 return sMand;
847}
848
849
850//
851//
852///////////////////////////////////////////////////////////////////////////////////////
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