source: trunk/source/processes/hadronic/stopping/src/G4AntiProtonAnnihilationAtRest.cc@ 1036

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[819]1//
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24// ********************************************************************
25//
26// G4AntiProtonAnnihilationAtRest physics process
27// Larry Felawka (TRIUMF), April 1998
28//---------------------------------------------------------------------
29
30#include "G4AntiProtonAnnihilationAtRest.hh"
31#include "G4DynamicParticle.hh"
32#include "G4ParticleTypes.hh"
33#include "Randomize.hh"
34#include <string.h>
35#include <cmath>
36#include <stdio.h>
37
38#define MAX_SECONDARIES 100
39
40// constructor
41
42G4AntiProtonAnnihilationAtRest::G4AntiProtonAnnihilationAtRest(const G4String& processName,
43 G4ProcessType aType ) :
44 G4VRestProcess (processName, aType), // initialization
45 massPionMinus(G4PionMinus::PionMinus()->GetPDGMass()/GeV),
46 massProton(G4Proton::Proton()->GetPDGMass()/GeV),
47 massPionZero(G4PionZero::PionZero()->GetPDGMass()/GeV),
48 massAntiProton(G4AntiProton::AntiProton()->GetPDGMass()/GeV),
49 massPionPlus(G4PionPlus::PionPlus()->GetPDGMass()/GeV),
50 massGamma(G4Gamma::Gamma()->GetPDGMass()/GeV),
51 pdefGamma(G4Gamma::Gamma()),
52 pdefPionPlus(G4PionPlus::PionPlus()),
53 pdefPionZero(G4PionZero::PionZero()),
54 pdefPionMinus(G4PionMinus::PionMinus()),
55 pdefProton(G4Proton::Proton()),
56 pdefAntiProton(G4AntiProton::AntiProton()),
57 pdefNeutron(G4Neutron::Neutron()),
58 pdefDeuteron(G4Deuteron::Deuteron()),
59 pdefTriton(G4Triton::Triton()),
60 pdefAlpha(G4Alpha::Alpha())
61{
62 if (verboseLevel>0) {
63 G4cout << GetProcessName() << " is created "<< G4endl;
64 }
[962]65 SetProcessSubType(fHadronAtRest);
[819]66 pv = new G4GHEKinematicsVector [MAX_SECONDARIES+1];
67 eve = new G4GHEKinematicsVector [MAX_SECONDARIES];
68 gkin = new G4GHEKinematicsVector [MAX_SECONDARIES];
69
70}
71
72// destructor
73
74G4AntiProtonAnnihilationAtRest::~G4AntiProtonAnnihilationAtRest()
75{
76 delete [] pv;
77 delete [] eve;
78 delete [] gkin;
79}
80
81
82// methods.............................................................................
83
84G4bool G4AntiProtonAnnihilationAtRest::IsApplicable(
85 const G4ParticleDefinition& particle
86 )
87{
88 return ( &particle == pdefAntiProton );
89
90}
91
92// Warning - this method may be optimized away if made "inline"
93G4int G4AntiProtonAnnihilationAtRest::GetNumberOfSecondaries()
94{
95 return ( ngkine );
96
97}
98
99// Warning - this method may be optimized away if made "inline"
100G4GHEKinematicsVector* G4AntiProtonAnnihilationAtRest::GetSecondaryKinematics()
101{
102 return ( &gkin[0] );
103
104}
105
106G4double G4AntiProtonAnnihilationAtRest::AtRestGetPhysicalInteractionLength(
107 const G4Track& track,
108 G4ForceCondition* condition
109 )
110{
111 // beggining of tracking
112 ResetNumberOfInteractionLengthLeft();
113
114 // condition is set to "Not Forced"
115 *condition = NotForced;
116
117 // get mean life time
118 currentInteractionLength = GetMeanLifeTime(track, condition);
119
120 if ((currentInteractionLength <0.0) || (verboseLevel>2)){
121 G4cout << "G4AntiProtonAnnihilationAtRestProcess::AtRestGetPhysicalInteractionLength ";
122 G4cout << "[ " << GetProcessName() << "]" <<G4endl;
123 track.GetDynamicParticle()->DumpInfo();
124 G4cout << " in Material " << track.GetMaterial()->GetName() <<G4endl;
125 G4cout << "MeanLifeTime = " << currentInteractionLength/ns << "[ns]" <<G4endl;
126 }
127
128 return theNumberOfInteractionLengthLeft * currentInteractionLength;
129
130}
131
132G4VParticleChange* G4AntiProtonAnnihilationAtRest::AtRestDoIt(
133 const G4Track& track,
134 const G4Step&
135 )
136//
137// Handles AntiProtons at rest; a AntiProton can either create secondaries or
138// do nothing (in which case it should be sent back to decay-handling
139// section
140//
141{
142
143// Initialize ParticleChange
144// all members of G4VParticleChange are set to equal to
145// corresponding member in G4Track
146
147 aParticleChange.Initialize(track);
148
149// Store some global quantities that depend on current material and particle
150
151 globalTime = track.GetGlobalTime()/s;
152 G4Material * aMaterial = track.GetMaterial();
153 const G4int numberOfElements = aMaterial->GetNumberOfElements();
154 const G4ElementVector* theElementVector = aMaterial->GetElementVector();
155
156 const G4double* theAtomicNumberDensity = aMaterial->GetAtomicNumDensityVector();
157 G4double normalization = 0;
158 for ( G4int i1=0; i1 < numberOfElements; i1++ )
159 {
160 normalization += theAtomicNumberDensity[i1] ; // change when nucleon specific
161 // probabilities are included.
162 }
163 G4double runningSum= 0.;
164 G4double random = G4UniformRand()*normalization;
165 for ( G4int i2=0; i2 < numberOfElements; i2++ )
166 {
167 runningSum += theAtomicNumberDensity[i2]; // change when nucleon specific
168 // probabilities are included.
169 if (random<=runningSum)
170 {
171 targetCharge = G4double((*theElementVector)[i2]->GetZ());
172 targetAtomicMass = (*theElementVector)[i2]->GetN();
173 }
174 }
175 if (random>runningSum)
176 {
177 targetCharge = G4double((*theElementVector)[numberOfElements-1]->GetZ());
178 targetAtomicMass = (*theElementVector)[numberOfElements-1]->GetN();
179
180 }
181
182 if (verboseLevel>1) {
183 G4cout << "G4AntiProtonAnnihilationAtRest::AtRestDoIt is invoked " <<G4endl;
184 }
185
186 G4ParticleMomentum momentum;
187 G4float localtime;
188
189 G4ThreeVector position = track.GetPosition();
190
191 GenerateSecondaries(); // Generate secondaries
192
193 aParticleChange.SetNumberOfSecondaries( ngkine );
194
195 for ( G4int isec = 0; isec < ngkine; isec++ ) {
196 G4DynamicParticle* aNewParticle = new G4DynamicParticle;
197 aNewParticle->SetDefinition( gkin[isec].GetParticleDef() );
198 aNewParticle->SetMomentum( gkin[isec].GetMomentum() * GeV );
199
200 localtime = globalTime + gkin[isec].GetTOF();
201
202 G4Track* aNewTrack = new G4Track( aNewParticle, localtime*s, position );
203 aNewTrack->SetTouchableHandle(track.GetTouchableHandle());
204 aParticleChange.AddSecondary( aNewTrack );
205
206 }
207
208 aParticleChange.ProposeLocalEnergyDeposit( 0.0*GeV );
209
210 aParticleChange.ProposeTrackStatus(fStopAndKill); // Kill the incident AntiProton
211
212// clear InteractionLengthLeft
213
214 ResetNumberOfInteractionLengthLeft();
215
216 return &aParticleChange;
217
218}
219
220
221void G4AntiProtonAnnihilationAtRest::GenerateSecondaries()
222{
223 static G4int index;
224 static G4int l;
225 static G4int nopt;
226 static G4int i;
227 static G4ParticleDefinition* jnd;
228
229 for (i = 1; i <= MAX_SECONDARIES; ++i) {
230 pv[i].SetZero();
231 }
232
233 ngkine = 0; // number of generated secondary particles
234 ntot = 0;
235 result.SetZero();
236 result.SetMass( massAntiProton );
237 result.SetKineticEnergyAndUpdate( 0. );
238 result.SetTOF( 0. );
239 result.SetParticleDef( pdefAntiProton );
240
241 AntiProtonAnnihilation(&nopt);
242
243 // *** CHECK WHETHER THERE ARE NEW PARTICLES GENERATED ***
244 if (ntot != 0 || result.GetParticleDef() != pdefAntiProton) {
245 // *** CURRENT PARTICLE IS NOT THE SAME AS IN THE BEGINNING OR/AND ***
246 // *** ONE OR MORE SECONDARIES HAVE BEEN GENERATED ***
247
248 // --- INITIAL PARTICLE TYPE HAS BEEN CHANGED ==> PUT NEW TYPE ON ---
249 // --- THE GEANT TEMPORARY STACK ---
250
251 // --- PUT PARTICLE ON THE STACK ---
252 gkin[0] = result;
253 gkin[0].SetTOF( result.GetTOF() * 5e-11 );
254 ngkine = 1;
255
256 // --- ALL QUANTITIES ARE TAKEN FROM THE GHEISHA STACK WHERE THE ---
257 // --- CONVENTION IS THE FOLLOWING ---
258
259 // --- ONE OR MORE SECONDARIES HAVE BEEN GENERATED ---
260 for (l = 1; l <= ntot; ++l) {
261 index = l - 1;
262 jnd = eve[index].GetParticleDef();
263
264 // --- ADD PARTICLE TO THE STACK IF STACK NOT YET FULL ---
265 if (ngkine < MAX_SECONDARIES) {
266 gkin[ngkine] = eve[index];
267 gkin[ngkine].SetTOF( eve[index].GetTOF() * 5e-11 );
268 ++ngkine;
269 }
270 }
271 }
272 else {
273 // --- NO SECONDARIES GENERATED AND PARTICLE IS STILL THE SAME ---
274 // --- ==> COPY EVERYTHING BACK IN THE CURRENT GEANT STACK ---
275 ngkine = 0;
276 ntot = 0;
277 globalTime += result.GetTOF() * G4float(5e-11);
278 }
279
280 // --- LIMIT THE VALUE OF NGKINE IN CASE OF OVERFLOW ---
281 ngkine = G4int(std::min(ngkine,G4int(MAX_SECONDARIES)));
282
283} // GenerateSecondaries
284
285
286void G4AntiProtonAnnihilationAtRest::Poisso(G4float xav, G4int *iran)
287{
288 static G4int i;
289 static G4float r, p1, p2, p3;
290 static G4int mm;
291 static G4float rr, ran, rrr, ran1;
292
293 // *** GENERATION OF POISSON DISTRIBUTION ***
294 // *** NVE 16-MAR-1988 CERN GENEVA ***
295 // ORIGIN : H.FESEFELDT (27-OCT-1983)
296
297 // --- USE NORMAL DISTRIBUTION FOR <X> > 9.9 ---
298 if (xav > G4float(9.9)) {
299 // ** NORMAL DISTRIBUTION WITH SIGMA**2 = <X>
300 Normal(&ran1);
301 ran1 = xav + ran1 * std::sqrt(xav);
302 *iran = G4int(ran1);
303 if (*iran < 0) {
304 *iran = 0;
305 }
306 }
307 else {
308 mm = G4int(xav * G4float(5.));
309 *iran = 0;
310 if (mm > 0) {
311 r = std::exp(-G4double(xav));
312 ran1 = G4UniformRand();
313 if (ran1 > r) {
314 rr = r;
315 for (i = 1; i <= mm; ++i) {
316 ++(*iran);
317 if (i <= 5) {
318 rrr = std::pow(xav, G4float(i)) / NFac(i);
319 }
320 // ** STIRLING' S FORMULA FOR LARGE NUMBERS
321 if (i > 5) {
322 rrr = std::exp(i * std::log(xav) -
323 (i + G4float(.5)) * std::log(i * G4float(1.)) +
324 i - G4float(.9189385));
325 }
326 rr += r * rrr;
327 if (ran1 <= rr) {
328 break;
329 }
330 }
331 }
332 }
333 else {
334 // ** FOR VERY SMALL XAV TRY IRAN=1,2,3
335 p1 = xav * std::exp(-G4double(xav));
336 p2 = xav * p1 / G4float(2.);
337 p3 = xav * p2 / G4float(3.);
338 ran = G4UniformRand();
339 if (ran >= p3) {
340 if (ran >= p2) {
341 if (ran >= p1) {
342 *iran = 0;
343 }
344 else {
345 *iran = 1;
346 }
347 }
348 else {
349 *iran = 2;
350 }
351 }
352 else {
353 *iran = 3;
354 }
355 }
356 }
357
358} // Poisso
359
360
361G4int G4AntiProtonAnnihilationAtRest::NFac(G4int n)
362{
363 G4int ret_val;
364
365 static G4int i, m;
366
367 // *** NVE 16-MAR-1988 CERN GENEVA ***
368 // ORIGIN : H.FESEFELDT (27-OCT-1983)
369
370 ret_val = 1;
371 m = n;
372 if (m > 1) {
373 if (m > 10) {
374 m = 10;
375 }
376 for (i = 2; i <= m; ++i) {
377 ret_val *= i;
378 }
379 }
380 return ret_val;
381
382} // NFac
383
384
385void G4AntiProtonAnnihilationAtRest::Normal(G4float *ran)
386{
387 static G4int i;
388
389 // *** NVE 14-APR-1988 CERN GENEVA ***
390 // ORIGIN : H.FESEFELDT (27-OCT-1983)
391
392 *ran = G4float(-6.);
393 for (i = 1; i <= 12; ++i) {
394 *ran += G4UniformRand();
395 }
396
397} // Normal
398
399
400void G4AntiProtonAnnihilationAtRest::AntiProtonAnnihilation(G4int *nopt)
401{
402 static G4float brr[3] = { G4float(.125),G4float(.25),G4float(.5) };
403
404 G4float r__1;
405
406 static G4int i, ii, kk;
407 static G4int nt;
408 static G4float cfa, eka;
409 static G4int ika, nbl;
410 static G4float ran, pcm;
411 static G4int isw;
412 static G4float tex;
413 static G4ParticleDefinition* ipa1;
414 static G4float ran1, ran2, ekin, tkin;
415 static G4float targ;
416 static G4ParticleDefinition* inve;
417 static G4float ekin1, ekin2, black;
418 static G4float pnrat, rmnve1, rmnve2;
419 static G4float ek, en;
420
421 // *** ANTI PROTON ANNIHILATION AT REST ***
422 // *** NVE 04-MAR-1988 CERN GENEVA ***
423 // ORIGIN : H.FESEFELDT (09-JULY-1987)
424
425 // NOPT=0 NO ANNIHILATION
426 // NOPT=1 ANNIH.IN PI+ PI-
427 // NOPT=2 ANNIH.IN PI0 PI0
428 // NOPT=3 ANNIH.IN PI- PI0
429 // NOPT=4 ANNIH.IN GAMMA GAMMA
430
431 pv[1].SetZero();
432 pv[1].SetMass( massAntiProton );
433 pv[1].SetKineticEnergyAndUpdate( 0. );
434 pv[1].SetTOF( result.GetTOF() );
435 pv[1].SetParticleDef( result.GetParticleDef() );
436 isw = 1;
437 ran = G4UniformRand();
438 if (ran > brr[0]) {
439 isw = 2;
440 }
441 if (ran > brr[1]) {
442 isw = 3;
443 }
444 if (ran > brr[2]) {
445 isw = 4;
446 }
447 *nopt = isw;
448 // **
449 // ** EVAPORATION
450 // **
451 if (isw == 1) {
452 rmnve1 = massPionPlus;
453 rmnve2 = massPionMinus;
454 }
455 else if (isw == 2) {
456 rmnve1 = massPionZero;
457 rmnve2 = massPionZero;
458 }
459 else if (isw == 3) {
460 rmnve1 = massPionMinus;
461 rmnve2 = massPionZero;
462 }
463 else if (isw == 4) {
464 rmnve1 = massGamma;
465 rmnve2 = massGamma;
466 }
467 ek = massProton + massAntiProton - rmnve1 - rmnve2;
468 tkin = ExNu(ek);
469 ek -= tkin;
470 if (ek < G4float(1e-4)) {
471 ek = G4float(1e-4);
472 }
473 ek *= G4float(.5);
474 en = ek + (rmnve1 + rmnve2) * G4float(.5);
475 r__1 = en * en - rmnve1 * rmnve2;
476 pcm = r__1 > 0 ? std::sqrt(r__1) : 0;
477 pv[2].SetZero();
478 pv[2].SetMass( rmnve1 );
479 pv[3].SetZero();
480 pv[3].SetMass( rmnve2 );
481 if (isw > 3) {
482 pv[2].SetMass( 0. );
483 pv[3].SetMass( 0. );
484 }
485 pv[2].SetEnergyAndUpdate( std::sqrt(pv[2].GetMass()*pv[2].GetMass()+pcm*pcm) );
486 pv[2].SetTOF( result.GetTOF() );
487 pv[3].SetEnergy( std::sqrt(pv[3].GetMass()*pv[3].GetMass()+pcm*pcm) );
488 pv[3].SetMomentumAndUpdate( -pv[2].GetMomentum().x(), -pv[2].GetMomentum().y(), -pv[2].GetMomentum().z() );
489 pv[3].SetTOF( result.GetTOF() );
490 switch ((int)isw) {
491 case 1:
492 pv[2].SetParticleDef( pdefPionPlus );
493 pv[3].SetParticleDef( pdefPionMinus );
494 break;
495 case 2:
496 pv[2].SetParticleDef( pdefPionZero );
497 pv[3].SetParticleDef( pdefPionZero );
498 break;
499 case 3:
500 pv[2].SetParticleDef( pdefPionMinus );
501 pv[3].SetParticleDef( pdefPionZero );
502 break;
503 case 4:
504 pv[2].SetParticleDef( pdefGamma );
505 pv[3].SetParticleDef( pdefGamma );
506 break;
507 default:
508 break;
509 }
510 nt = 3;
511 if (targetAtomicMass >= G4float(1.5)) {
512 cfa = (targetAtomicMass - G4float(1.)) /
513 G4float(120.) * G4float(.025) *
514 std::exp(-G4double(targetAtomicMass - G4float(1.)) / G4float(120.));
515 targ = G4float(1.);
516 tex = evapEnergy1;
517 if (tex >= G4float(.001)) {
518 black = (targ * G4float(1.25) +
519 G4float(1.5)) * evapEnergy1 / (evapEnergy1 + evapEnergy3);
520 Poisso(black, &nbl);
521 if (G4float(G4int(targ) + nbl) > targetAtomicMass) {
522 nbl = G4int(targetAtomicMass - targ);
523 }
524 if (nt + nbl > (MAX_SECONDARIES - 2)) {
525 nbl = (MAX_SECONDARIES - 2) - nt;
526 }
527 if (nbl > 0) {
528 ekin = tex / nbl;
529 ekin2 = G4float(0.);
530 for (i = 1; i <= nbl; ++i) {
531 if (nt == (MAX_SECONDARIES - 2)) {
532 continue;
533 }
534 if (ekin2 > tex) {
535 break;
536 }
537 ran1 = G4UniformRand();
538 Normal(&ran2);
539 ekin1 = -G4double(ekin) * std::log(ran1) -
540 cfa * (ran2 * G4float(.5) + G4float(1.));
541 if (ekin1 < G4float(0.)) {
542 ekin1 = std::log(ran1) * G4float(-.01);
543 }
544 ekin1 *= G4float(1.);
545 ekin2 += ekin1;
546 if (ekin2 > tex) {
547 ekin1 = tex - (ekin2 - ekin1);
548 }
549 if (ekin1 < G4float(0.)) {
550 ekin1 = G4float(.001);
551 }
552 ipa1 = pdefNeutron;
553 pnrat = G4float(1.) - targetCharge / targetAtomicMass;
554 if (G4UniformRand() > pnrat) {
555 ipa1 = pdefProton;
556 }
557 ++nt;
558 pv[nt].SetZero();
559 pv[nt].SetMass( ipa1->GetPDGMass()/GeV );
560 pv[nt].SetKineticEnergyAndUpdate( ekin1 );
561 pv[nt].SetTOF( result.GetTOF() );
562 pv[nt].SetParticleDef( ipa1 );
563 }
564 if (targetAtomicMass >= G4float(230.) && ek <= G4float(2.)) {
565 ii = nt + 1;
566 kk = 0;
567 eka = ek;
568 if (eka > G4float(1.)) {
569 eka *= eka;
570 }
571 if (eka < G4float(.1)) {
572 eka = G4float(.1);
573 }
574 ika = G4int(G4float(3.6) / eka);
575 for (i = 1; i <= nt; ++i) {
576 --ii;
577 if (pv[ii].GetParticleDef() != pdefProton) {
578 continue;
579 }
580 ipa1 = pdefNeutron;
581 pv[ii].SetMass( ipa1->GetPDGMass()/GeV );
582 pv[ii].SetParticleDef( ipa1 );
583 ++kk;
584 if (kk > ika) {
585 break;
586 }
587 }
588 }
589 }
590 }
591 // **
592 // ** THEN ALSO DEUTERONS, TRITONS AND ALPHAS
593 // **
594 tex = evapEnergy3;
595 if (tex >= G4float(.001)) {
596 black = (targ * G4float(1.25) + G4float(1.5)) * evapEnergy3 /
597 (evapEnergy1 + evapEnergy3);
598 Poisso(black, &nbl);
599 if (nt + nbl > (MAX_SECONDARIES - 2)) {
600 nbl = (MAX_SECONDARIES - 2) - nt;
601 }
602 if (nbl > 0) {
603 ekin = tex / nbl;
604 ekin2 = G4float(0.);
605 for (i = 1; i <= nbl; ++i) {
606 if (nt == (MAX_SECONDARIES - 2)) {
607 continue;
608 }
609 if (ekin2 > tex) {
610 break;
611 }
612 ran1 = G4UniformRand();
613 Normal(&ran2);
614 ekin1 = -G4double(ekin) * std::log(ran1) -
615 cfa * (ran2 * G4float(.5) + G4float(1.));
616 if (ekin1 < G4float(0.)) {
617 ekin1 = std::log(ran1) * G4float(-.01);
618 }
619 ekin1 *= G4float(1.);
620 ekin2 += ekin1;
621 if (ekin2 > tex) {
622 ekin1 = tex - (ekin2 - ekin1);
623 }
624 if (ekin1 < G4float(0.)) {
625 ekin1 = G4float(.001);
626 }
627 ran = G4UniformRand();
628 inve = pdefDeuteron;
629 if (ran > G4float(.6)) {
630 inve = pdefTriton;
631 }
632 if (ran > G4float(.9)) {
633 inve = pdefAlpha;
634 }
635 ++nt;
636 pv[nt].SetZero();
637 pv[nt].SetMass( inve->GetPDGMass()/GeV );
638 pv[nt].SetKineticEnergyAndUpdate( ekin1 );
639 pv[nt].SetTOF( result.GetTOF() );
640 pv[nt].SetParticleDef( inve );
641 }
642 }
643 }
644 }
645 result = pv[2];
646 if (nt == 2) {
647 return;
648 }
649 for (i = 3; i <= nt; ++i) {
650 if (ntot >= MAX_SECONDARIES) {
651 return;
652 }
653 eve[ntot++] = pv[i];
654 }
655
656} // AntiProtonAnnihilation
657
658
659G4double G4AntiProtonAnnihilationAtRest::ExNu(G4float ek1)
660{
661 G4float ret_val, r__1;
662
663 static G4float cfa, gfa, ran1, ran2, ekin1, atno3;
664 static G4int magic;
665 static G4float fpdiv;
666
667 // *** NUCLEAR EVAPORATION AS FUNCTION OF ATOMIC NUMBER ATNO ***
668 // *** AND KINETIC ENERGY EKIN OF PRIMARY PARTICLE ***
669 // *** NVE 04-MAR-1988 CERN GENEVA ***
670 // ORIGIN : H.FESEFELDT (10-DEC-1986)
671
672 ret_val = G4float(0.);
673 if (targetAtomicMass >= G4float(1.5)) {
674 magic = 0;
675 if (G4int(targetCharge + G4float(.1)) == 82) {
676 magic = 1;
677 }
678 ekin1 = ek1;
679 if (ekin1 < G4float(.1)) {
680 ekin1 = G4float(.1);
681 }
682 if (ekin1 > G4float(4.)) {
683 ekin1 = G4float(4.);
684 }
685 // ** 0.35 VALUE AT 1 GEV
686 // ** 0.05 VALUE AT 0.1 GEV
687 cfa = G4float(.13043478260869565);
688 cfa = cfa * std::log(ekin1) + G4float(.35);
689 if (cfa < G4float(.15)) {
690 cfa = G4float(.15);
691 }
692 ret_val = cfa * G4float(7.716) * std::exp(-G4double(cfa));
693 atno3 = targetAtomicMass;
694 if (atno3 > G4float(120.)) {
695 atno3 = G4float(120.);
696 }
697 cfa = (atno3 - G4float(1.)) /
698 G4float(120.) * std::exp(-G4double(atno3 - G4float(1.)) / G4float(120.));
699 ret_val *= cfa;
700 r__1 = ekin1;
701 fpdiv = G4float(1.) - r__1 * r__1 * G4float(.25);
702 if (fpdiv < G4float(.5)) {
703 fpdiv = G4float(.5);
704 }
705 gfa = (targetAtomicMass - G4float(1.)) /
706 G4float(70.) * G4float(2.) *
707 std::exp(-G4double(targetAtomicMass - G4float(1.)) / G4float(70.));
708 evapEnergy1 = ret_val * fpdiv;
709 evapEnergy3 = ret_val - evapEnergy1;
710 Normal(&ran1);
711 Normal(&ran2);
712 if (magic == 1) {
713 ran1 = G4float(0.);
714 ran2 = G4float(0.);
715 }
716 evapEnergy1 *= ran1 * gfa + G4float(1.);
717 if (evapEnergy1 < G4float(0.)) {
718 evapEnergy1 = G4float(0.);
719 }
720 evapEnergy3 *= ran2 * gfa + G4float(1.);
721 if (evapEnergy3 < G4float(0.)) {
722 evapEnergy3 = G4float(0.);
723 }
724 while ((ret_val = evapEnergy1 + evapEnergy3) >= ek1) {
725 evapEnergy1 *= G4float(1.) - G4UniformRand() * G4float(.5);
726 evapEnergy3 *= G4float(1.) - G4UniformRand() * G4float(.5);
727 }
728 }
729 return ret_val;
730
731} // ExNu
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