source: trunk/source/processes/hadronic/models/high_energy/src/G4HEKaonZeroInelastic.cc@ 1350

Last change on this file since 1350 was 1347, checked in by garnier, 15 years ago

geant4 tag 9.4
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25//
26// $Id: G4HEKaonZeroInelastic.cc,v 1.18 2010/11/29 05:44:44 dennis Exp $
27// GEANT4 tag $Name: geant4-09-04-ref-00 $
28//
29
30#include "globals.hh"
31#include "G4ios.hh"
32
33// G4 Process: Gheisha High Energy Collision model.
34// This includes the high energy cascading model, the two-body-resonance model
35// and the low energy two-body model. Not included are the low energy stuff
36// like nuclear reactions, nuclear fission without any cascading and all
37// processes for particles at rest.
38// First work done by J.L.Chuma and F.W.Jones, TRIUMF, June 96.
39// H. Fesefeldt, RWTH-Aachen, 23-October-1996
40// Last modified: 29-July-1998
41
42#include "G4HEKaonZeroInelastic.hh"
43
44G4HadFinalState*
45G4HEKaonZeroInelastic::ApplyYourself(const G4HadProjectile& aTrack,
46 G4Nucleus& targetNucleus)
47{
48 G4HEVector* pv = new G4HEVector[MAXPART];
49 const G4HadProjectile* aParticle = &aTrack;
50 const G4double A = targetNucleus.GetN();
51 const G4double Z = targetNucleus.GetZ();
52 G4HEVector incidentParticle(aParticle);
53
54 G4double atomicNumber = Z;
55 G4double atomicWeight = A;
56
57 G4int incidentCode = incidentParticle.getCode();
58 G4double incidentMass = incidentParticle.getMass();
59 G4double incidentTotalEnergy = incidentParticle.getEnergy();
60 G4double incidentTotalMomentum = incidentParticle.getTotalMomentum();
61 G4double incidentKineticEnergy = incidentTotalEnergy - incidentMass;
62
63 if (incidentKineticEnergy < 1.)
64 G4cout << "GHEKaonZeroInelastic: incident energy < 1 GeV" << G4endl;;
65
66 if (verboseLevel > 1) {
67 G4cout << "G4HEKaonZeroInelastic::ApplyYourself" << G4endl;
68 G4cout << "incident particle " << incidentParticle.getName()
69 << "mass " << incidentMass
70 << "kinetic energy " << incidentKineticEnergy
71 << G4endl;
72 G4cout << "target material with (A,Z) = ("
73 << atomicWeight << "," << atomicNumber << ")" << G4endl;
74 }
75
76 G4double inelasticity = NuclearInelasticity(incidentKineticEnergy,
77 atomicWeight, atomicNumber);
78 if (verboseLevel > 1)
79 G4cout << "nuclear inelasticity = " << inelasticity << G4endl;
80
81 incidentKineticEnergy -= inelasticity;
82
83 G4double excitationEnergyGNP = 0.;
84 G4double excitationEnergyDTA = 0.;
85
86 G4double excitation = NuclearExcitation(incidentKineticEnergy,
87 atomicWeight, atomicNumber,
88 excitationEnergyGNP,
89 excitationEnergyDTA);
90 if (verboseLevel > 1)
91 G4cout << "nuclear excitation = " << excitation << excitationEnergyGNP
92 << excitationEnergyDTA << G4endl;
93
94 incidentKineticEnergy -= excitation;
95 incidentTotalEnergy = incidentKineticEnergy + incidentMass;
96 incidentTotalMomentum = std::sqrt( (incidentTotalEnergy-incidentMass)
97 *(incidentTotalEnergy+incidentMass));
98
99 G4HEVector targetParticle;
100 if (G4UniformRand() < atomicNumber/atomicWeight) {
101 targetParticle.setDefinition("Proton");
102 } else {
103 targetParticle.setDefinition("Neutron");
104 }
105
106 G4double targetMass = targetParticle.getMass();
107 G4double centerOfMassEnergy = std::sqrt(incidentMass*incidentMass
108 + targetMass*targetMass
109 + 2.0*targetMass*incidentTotalEnergy);
110 G4double availableEnergy = centerOfMassEnergy - targetMass - incidentMass;
111
112 G4bool inElastic = true;
113 vecLength = 0;
114
115 if (verboseLevel > 1)
116 G4cout << "ApplyYourself: CallFirstIntInCascade for particle "
117 << incidentCode << G4endl;
118
119 G4bool successful = false;
120
121 FirstIntInCasKaonZero(inElastic, availableEnergy, pv, vecLength,
122 incidentParticle, targetParticle, atomicWeight);
123
124 if (verboseLevel > 1)
125 G4cout << "ApplyYourself::StrangeParticlePairProduction" << G4endl;
126
127 if ((vecLength > 0) && (availableEnergy > 1.))
128 StrangeParticlePairProduction(availableEnergy, centerOfMassEnergy,
129 pv, vecLength,
130 incidentParticle, targetParticle);
131
132 HighEnergyCascading(successful, pv, vecLength,
133 excitationEnergyGNP, excitationEnergyDTA,
134 incidentParticle, targetParticle,
135 atomicWeight, atomicNumber);
136 if (!successful)
137 HighEnergyClusterProduction(successful, pv, vecLength,
138 excitationEnergyGNP, excitationEnergyDTA,
139 incidentParticle, targetParticle,
140 atomicWeight, atomicNumber);
141 if (!successful)
142 MediumEnergyCascading(successful, pv, vecLength,
143 excitationEnergyGNP, excitationEnergyDTA,
144 incidentParticle, targetParticle,
145 atomicWeight, atomicNumber);
146
147 if (!successful)
148 MediumEnergyClusterProduction(successful, pv, vecLength,
149 excitationEnergyGNP, excitationEnergyDTA,
150 incidentParticle, targetParticle,
151 atomicWeight, atomicNumber);
152 if (!successful)
153 QuasiElasticScattering(successful, pv, vecLength,
154 excitationEnergyGNP, excitationEnergyDTA,
155 incidentParticle, targetParticle,
156 atomicWeight, atomicNumber);
157 if (!successful)
158 ElasticScattering(successful, pv, vecLength,
159 incidentParticle,
160 atomicWeight, atomicNumber);
161
162 if (!successful)
163 G4cout << "GHEInelasticInteraction::ApplyYourself fails to produce final state particles"
164 << G4endl;
165
166 FillParticleChange(pv, vecLength);
167
168 delete [] pv;
169 theParticleChange.SetStatusChange(stopAndKill);
170 return &theParticleChange;
171}
172
173
174void
175G4HEKaonZeroInelastic::FirstIntInCasKaonZero(G4bool& inElastic,
176 const G4double availableEnergy,
177 G4HEVector pv[],
178 G4int& vecLen,
179 const G4HEVector& incidentParticle,
180 const G4HEVector& targetParticle,
181 const G4double atomicWeight)
182
183// Kaon0 undergoes interaction with nucleon within a nucleus. Check if it is
184// energetically possible to produce pions/kaons. In not, assume nuclear excitation
185// occurs and input particle is degraded in energy. No other particles are produced.
186// If reaction is possible, find the correct number of pions/protons/neutrons
187// produced using an interpolation to multiplicity data. Replace some pions or
188// protons/neutrons by kaons or strange baryons according to the average
189// multiplicity per inelastic reaction.
190{
191 static const G4double expxu = std::log(MAXFLOAT); // upper bound for arg. of exp
192 static const G4double expxl = -expxu; // lower bound for arg. of exp
193
194 static const G4double protb = 0.7;
195 static const G4double neutb = 0.7;
196 static const G4double c = 1.25;
197
198 static const G4int numMul = 1200;
199 static const G4int numSec = 60;
200
201 G4int neutronCode = Neutron.getCode();
202 G4int protonCode = Proton.getCode();
203
204 G4int targetCode = targetParticle.getCode();
205 G4double incidentTotalMomentum = incidentParticle.getTotalMomentum();
206
207 static G4bool first = true;
208 static G4double protmul[numMul], protnorm[numSec]; // proton constants
209 static G4double neutmul[numMul], neutnorm[numSec]; // neutron constants
210
211 // misc. local variables
212 // np = number of pi+, nm = number of pi-, nz = number of pi0
213
214 G4int i, counter, nt, np, nm, nz;
215
216 if( first )
217 { // compute normalization constants, this will only be done once
218 first = false;
219 for( i=0; i<numMul; i++ )protmul[i] = 0.0;
220 for( i=0; i<numSec; i++ )protnorm[i] = 0.0;
221 counter = -1;
222 for( np=0; np<(numSec/3); np++ )
223 {
224 for( nm=std::max(0,np-1); nm<=(np+1); nm++ )
225 {
226 for( nz=0; nz<numSec/3; nz++ )
227 {
228 if( ++counter < numMul )
229 {
230 nt = np+nm+nz;
231 if( (nt>0) && (nt<=numSec) )
232 {
233 protmul[counter] =
234 pmltpc(np,nm,nz,nt,protb,c) ;
235 protnorm[nt-1] += protmul[counter];
236 }
237 }
238 }
239 }
240 }
241 for( i=0; i<numMul; i++ )neutmul[i] = 0.0;
242 for( i=0; i<numSec; i++ )neutnorm[i] = 0.0;
243 counter = -1;
244 for( np=0; np<numSec/3; np++ )
245 {
246 for( nm=np; nm<=(np+2); nm++ )
247 {
248 for( nz=0; nz<numSec/3; nz++ )
249 {
250 if( ++counter < numMul )
251 {
252 nt = np+nm+nz;
253 if( (nt>0) && (nt<=numSec) )
254 {
255 neutmul[counter] =
256 pmltpc(np,nm,nz,nt,neutb,c);
257 neutnorm[nt-1] += neutmul[counter];
258 }
259 }
260 }
261 }
262 }
263 for( i=0; i<numSec; i++ )
264 {
265 if( protnorm[i] > 0.0 )protnorm[i] = 1.0/protnorm[i];
266 if( neutnorm[i] > 0.0 )neutnorm[i] = 1.0/neutnorm[i];
267 }
268 } // end of initialization
269
270
271 // initialize the first two places
272 // the same as beam and target
273 pv[0] = incidentParticle;
274 pv[1] = targetParticle;
275 vecLen = 2;
276
277 if( !inElastic )
278 { // quasi-elastic scattering, no pions produced
279 if( targetCode == protonCode )
280 {
281 G4double cech[] = {0.33,0.27,0.29,0.31,0.27,0.18,0.13,0.10,0.09,0.07};
282 G4int iplab = G4int( std::min( 9.0, incidentTotalMomentum*5. ) );
283 if( G4UniformRand() < cech[iplab]/std::pow(atomicWeight,0.42) )
284 { // charge exchange K+ n -> K0 p
285 pv[0] = KaonPlus;
286 pv[1] = Neutron;
287 }
288 }
289 return;
290 }
291 else if (availableEnergy <= PionPlus.getMass())
292 return;
293
294 // inelastic scattering
295
296 np = 0, nm = 0, nz = 0;
297 G4double eab = availableEnergy;
298 G4int ieab = G4int( eab*5.0 );
299
300 G4double supp[] = {0., 0.4, 0.55, 0.65, 0.75, 0.82, 0.86, 0.90, 0.94, 0.98};
301 if( (ieab <= 9) && (G4UniformRand() >= supp[ieab]) )
302 {
303// suppress high multiplicity events at low momentum
304// only one additional pion will be produced
305 G4double w0, wp, wm, wt, ran;
306 if( targetCode == neutronCode ) // target is a neutron
307 {
308 w0 = - sqr(1.+protb)/(2.*c*c);
309 w0 = std::exp(w0);
310 wm = - sqr(-1.+protb)/(2.*c*c);
311 wm = std::exp(wm);
312 w0 = w0/2.;
313 wm = wm*1.5;
314 if( G4UniformRand() < w0/(w0+wm) ) { np = 0; nm = 0; nz = 1; }
315 else
316 { np = 0; nm = 1; nz = 0; }
317 }
318 else
319 { // target is a proton
320 w0 = -sqr(1.+neutb)/(2.*c*c);
321 wp = w0 = std::exp(w0);
322 wm = -sqr(-1.+neutb)/(2.*c*c);
323 wm = std::exp(wm);
324 wt = w0+wp+wm;
325 wp = w0+wp;
326 ran = G4UniformRand();
327 if( ran < w0/wt)
328 { np = 0; nm = 0; nz = 1; }
329 else if( ran < wp/wt)
330 { np = 1; nm = 0; nz = 0; }
331 else
332 { np = 0; nm = 1; nz = 0; }
333 }
334 }
335 else
336 {
337// number of total particles vs. centre of mass Energy - 2*proton mass
338
339 G4double aleab = std::log(availableEnergy);
340 G4double n = 3.62567+aleab*(0.665843+aleab*(0.336514
341 + aleab*(0.117712+0.0136912*aleab))) - 2.0;
342
343// normalization constant for kno-distribution.
344// calculate first the sum of all constants, check for numerical problems.
345 G4double test, dum, anpn = 0.0;
346
347 for (nt=1; nt<=numSec; nt++) {
348 test = std::exp( std::min( expxu, std::max( expxl, -(pi/4.0)*(nt*nt)/(n*n) ) ) );
349 dum = pi*nt/(2.0*n*n);
350 if (std::fabs(dum) < 1.0) {
351 if( test >= 1.0e-10 )anpn += dum*test;
352 } else {
353 anpn += dum*test;
354 }
355 }
356
357 G4double ran = G4UniformRand();
358 G4double excs = 0.0;
359 if( targetCode == protonCode )
360 {
361 counter = -1;
362 for( np=0; np<numSec/3; np++ )
363 {
364 for( nm=std::max(0,np-1); nm<=(np+1); nm++ )
365 {
366 for (nz=0; nz<numSec/3; nz++) {
367 if (++counter < numMul) {
368 nt = np+nm+nz;
369 if ( (nt>0) && (nt<=numSec) ) {
370 test = std::exp( std::min( expxu, std::max( expxl, -(pi/4.0)*(nt*nt)/(n*n) ) ) );
371 dum = (pi/anpn)*nt*protmul[counter]*protnorm[nt-1]/(2.0*n*n);
372 if (std::fabs(dum) < 1.0) {
373 if( test >= 1.0e-10 )excs += dum*test;
374 } else {
375 excs += dum*test;
376 }
377 if (ran < excs) goto outOfLoop; //----------------------->
378 }
379 }
380 }
381 }
382 }
383
384 // 3 previous loops continued to the end
385 inElastic = false; // quasi-elastic scattering
386 return;
387 }
388 else
389 { // target must be a neutron
390 counter = -1;
391 for( np=0; np<numSec/3; np++ )
392 {
393 for( nm=np; nm<=(np+2); nm++ )
394 {
395 for (nz=0; nz<numSec/3; nz++) {
396 if (++counter < numMul) {
397 nt = np+nm+nz;
398 if ( (nt>=1) && (nt<=numSec) ) {
399 test = std::exp( std::min( expxu, std::max( expxl, -(pi/4.0)*(nt*nt)/(n*n) ) ) );
400 dum = (pi/anpn)*nt*neutmul[counter]*neutnorm[nt-1]/(2.0*n*n);
401 if (std::fabs(dum) < 1.0) {
402 if( test >= 1.0e-10 )excs += dum*test;
403 } else {
404 excs += dum*test;
405 }
406 if (ran < excs) goto outOfLoop; // -------------------------->
407 }
408 }
409 }
410 }
411 }
412 // 3 previous loops continued to the end
413 inElastic = false; // quasi-elastic scattering.
414 return;
415 }
416 }
417 outOfLoop: // <-----------------------------------------------
418
419 if( targetCode == neutronCode)
420 {
421 if( np == nm)
422 {
423 }
424 else if (np == (nm-1))
425 {
426 if( G4UniformRand() < 0.5)
427 {
428 pv[0] = KaonPlus;
429 }
430 else
431 {
432 pv[1] = Proton;
433 }
434 }
435 else
436 {
437 pv[0] = KaonPlus;
438 pv[1] = Proton;
439 }
440 }
441 else
442 {
443 if( np == nm )
444 {
445 if( G4UniformRand() < 0.25)
446 {
447 pv[0] = KaonPlus;
448 pv[1] = Neutron;
449 }
450 else
451 {
452 }
453 }
454 else if ( np == (nm+1))
455 {
456 pv[1] = Neutron;
457 }
458 else
459 {
460 pv[0] = KaonPlus;
461 }
462 }
463
464
465 nt = np + nm + nz;
466 while ( nt > 0)
467 {
468 G4double ran = G4UniformRand();
469 if ( ran < (G4double)np/nt)
470 {
471 if( np > 0 )
472 { pv[vecLen++] = PionPlus;
473 np--;
474 }
475 }
476 else if ( ran < (G4double)(np+nm)/nt)
477 {
478 if( nm > 0 )
479 {
480 pv[vecLen++] = PionMinus;
481 nm--;
482 }
483 }
484 else
485 {
486 if( nz > 0 )
487 {
488 pv[vecLen++] = PionZero;
489 nz--;
490 }
491 }
492 nt = np + nm + nz;
493 }
494 if (verboseLevel > 1)
495 {
496 G4cout << "Particles produced: " ;
497 G4cout << pv[0].getName() << " " ;
498 G4cout << pv[1].getName() << " " ;
499 for (i=2; i < vecLen; i++)
500 {
501 G4cout << pv[i].getName() << " " ;
502 }
503 G4cout << G4endl;
504 }
505 return; }
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