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Geant4/processes/electromagnetic/lowenergy/src/G4LowEPComptonModel.cc

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Differences between /processes/electromagnetic/lowenergy/src/G4LowEPComptonModel.cc (Version 11.3.0) and /processes/electromagnetic/lowenergy/src/G4LowEPComptonModel.cc (Version 8.0.p1)


  1 //                                                  1 
  2 // *******************************************    
  3 // * License and Disclaimer                       
  4 // *                                              
  5 // * The  Geant4 software  is  copyright of th    
  6 // * the Geant4 Collaboration.  It is provided    
  7 // * conditions of the Geant4 Software License    
  8 // * LICENSE and available at  http://cern.ch/    
  9 // * include a list of copyright holders.         
 10 // *                                              
 11 // * Neither the authors of this software syst    
 12 // * institutes,nor the agencies providing fin    
 13 // * work  make  any representation or  warran    
 14 // * regarding  this  software system or assum    
 15 // * use.  Please see the license in the file     
 16 // * for the full disclaimer and the limitatio    
 17 // *                                              
 18 // * This  code  implementation is the result     
 19 // * technical work of the GEANT4 collaboratio    
 20 // * By using,  copying,  modifying or  distri    
 21 // * any work based  on the software)  you  ag    
 22 // * use  in  resulting  scientific  publicati    
 23 // * acceptance of all terms of the Geant4 Sof    
 24 // *******************************************    
 25 // *******************************************    
 26 // *******************************************    
 27 // |                                              
 28 // |             G4LowEPComptonModel-- Geant4     
 29 // |                   low energy Compton scat    
 30 // |             J. M. C. Brown, Monash Univer    
 31 // |                    ## Unpolarised photons    
 32 // |                                              
 33 // |                                              
 34 // *******************************************    
 35 // |                                              
 36 // | The following is a Geant4 class to simula    
 37 // | bound electron Compton scattering. Genera    
 38 // | based on G4LowEnergyCompton.cc and G4Live    
 39 // | Algorithms for photon energy, and ejected    
 40 // | direction taken from:                        
 41 // |                                              
 42 // | J. M. C. Brown, M. R. Dimmock, J. E. Gill    
 43 // | "A low energy bound atomic electron Compt    
 44 // |  for Geant4", NIMB, Vol. 338, 77-88, 2014    
 45 // |                                              
 46 // | The author acknowledges the work of the G    
 47 // | in developing the following algorithms th    
 48 // | or adapeted for the present software:        
 49 // |                                              
 50 // |  # sampling of photon scattering angle,      
 51 // |  # target element selection in composite     
 52 // |  # target shell selection in element,        
 53 // |  # and sampling of bound electron momentu    
 54 // |                                              
 55 // *******************************************    
 56 // |                                              
 57 // | History:                                     
 58 // | --------                                     
 59 // |                                              
 60 // | Nov. 2011 JMCB       - First version         
 61 // | Feb. 2012 JMCB       - Migration to Geant    
 62 // | Sep. 2012 JMCB       - Final fixes for Ge    
 63 // | Feb. 2013 JMCB       - Geant4 9.6 FPE fix    
 64 // | Jan. 2015 JMCB       - Migration to MT (B    
 65 // |                        implementation)       
 66 // | Feb. 2016 JMCB       - Geant4 10.2 FPE fi    
 67 // |                                              
 68 // *******************************************    
 69                                                   
 70 #include <limits>                                 
 71 #include "G4LowEPComptonModel.hh"                 
 72 #include "G4PhysicalConstants.hh"                 
 73 #include "G4SystemOfUnits.hh"                     
 74 #include "G4Electron.hh"                          
 75 #include "G4ParticleChangeForGamma.hh"            
 76 #include "G4LossTableManager.hh"                  
 77 #include "G4VAtomDeexcitation.hh"                 
 78 #include "G4AtomicShell.hh"                       
 79 #include "G4AutoLock.hh"                          
 80 #include "G4Gamma.hh"                             
 81 #include "G4ShellData.hh"                         
 82 #include "G4DopplerProfile.hh"                    
 83 #include "G4Log.hh"                               
 84 #include "G4Exp.hh"                               
 85                                                   
 86 //********************************************    
 87                                                   
 88 using namespace std;                              
 89 namespace { G4Mutex LowEPComptonModelMutex = G    
 90                                                   
 91 G4PhysicsFreeVector* G4LowEPComptonModel::data    
 92 G4ShellData*       G4LowEPComptonModel::shellD    
 93 G4DopplerProfile*  G4LowEPComptonModel::profil    
 94                                                   
 95 static const G4double ln10 = G4Log(10.);          
 96                                                   
 97 G4LowEPComptonModel::G4LowEPComptonModel(const    
 98                                                   
 99   : G4VEmModel(nam),isInitialised(false)          
100 {                                                 
101   verboseLevel=1 ;                                
102   // Verbosity scale:                             
103   // 0 = nothing                                  
104   // 1 = warning for energy non-conservation      
105   // 2 = details of energy budget                 
106   // 3 = calculation of cross sections, file o    
107   // 4 = entering in methods                      
108                                                   
109   if(  verboseLevel>1 ) {                         
110     G4cout << "Low energy photon Compton model    
111   }                                               
112                                                   
113   //Mark this model as "applicable" for atomic    
114   SetDeexcitationFlag(true);                      
115                                                   
116   fParticleChange = nullptr;                      
117   fAtomDeexcitation = nullptr;                    
118 }                                                 
119                                                   
120 //********************************************    
121                                                   
122 G4LowEPComptonModel::~G4LowEPComptonModel()       
123 {                                                 
124   if(IsMaster()) {                                
125     delete shellData;                             
126     shellData = nullptr;                          
127     delete profileData;                           
128     profileData = nullptr;                        
129   }                                               
130 }                                                 
131                                                   
132 //********************************************    
133                                                   
134 void G4LowEPComptonModel::Initialise(const G4P    
135                                      const G4D    
136 {                                                 
137   if (verboseLevel > 1) {                         
138     G4cout << "Calling G4LowEPComptonModel::In    
139   }                                               
140                                                   
141   // Initialise element selector                  
142   if(IsMaster()) {                                
143                                                   
144     // Access to elements                         
145     const char* path = G4FindDataDir("G4LEDATA    
146                                                   
147     G4ProductionCutsTable* theCoupleTable =       
148       G4ProductionCutsTable::GetProductionCuts    
149     G4int numOfCouples = (G4int)theCoupleTable    
150                                                   
151     for(G4int i=0; i<numOfCouples; ++i) {         
152       const G4Material* material =                
153         theCoupleTable->GetMaterialCutsCouple(    
154       const G4ElementVector* theElementVector     
155       std::size_t nelm = material->GetNumberOf    
156                                                   
157       for (std::size_t j=0; j<nelm; ++j) {        
158         G4int Z = G4lrint((*theElementVector)[    
159         if(Z < 1)        { Z = 1; }               
160         else if(Z > maxZ){ Z = maxZ; }            
161                                                   
162         if( (!data[Z]) ) { ReadData(Z, path);     
163       }                                           
164     }                                             
165                                                   
166     // For Doppler broadening                     
167     if(!shellData) {                              
168       shellData = new G4ShellData();              
169       shellData->SetOccupancyData();              
170       G4String file = "/doppler/shell-doppler"    
171       shellData->LoadData(file);                  
172     }                                             
173     if(!profileData) { profileData = new G4Dop    
174                                                   
175     InitialiseElementSelectors(particle, cuts)    
176   }                                               
177                                                   
178   if (verboseLevel > 2) {                         
179     G4cout << "Loaded cross section files" <<     
180   }                                               
181                                                   
182   if( verboseLevel>1 ) {                          
183     G4cout << "G4LowEPComptonModel is initiali    
184            << "Energy range: "                    
185            << LowEnergyLimit() / eV << " eV -     
186            << HighEnergyLimit() / GeV << " GeV    
187            << G4endl;                             
188   }                                               
189                                                   
190   if(isInitialised) { return; }                   
191                                                   
192   fParticleChange = GetParticleChangeForGamma(    
193   fAtomDeexcitation  = G4LossTableManager::Ins    
194   isInitialised = true;                           
195 }                                                 
196                                                   
197 //********************************************    
198                                                   
199 void G4LowEPComptonModel::InitialiseLocal(cons    
200                                                   
201 {                                                 
202   SetElementSelectors(masterModel->GetElementS    
203 }                                                 
204                                                   
205 //********************************************    
206                                                   
207 void G4LowEPComptonModel::ReadData(std::size_t    
208 {                                                 
209   if (verboseLevel > 1)                           
210   {                                               
211     G4cout << "G4LowEPComptonModel::ReadData()    
212            << G4endl;                             
213   }                                               
214   if(data[Z]) { return; }                         
215   const char* datadir = path;                     
216   if(!datadir)                                    
217   {                                               
218     datadir = G4FindDataDir("G4LEDATA");          
219     if(!datadir)                                  
220     {                                             
221       G4Exception("G4LowEPComptonModel::ReadDa    
222                   "em0006",FatalException,        
223                   "Environment variable G4LEDA    
224       return;                                     
225     }                                             
226   }                                               
227                                                   
228   data[Z] = new G4PhysicsFreeVector();            
229                                                   
230   std::ostringstream ost;                         
231   ost << datadir << "/livermore/comp/ce-cs-" <    
232   std::ifstream fin(ost.str().c_str());           
233                                                   
234   if( !fin.is_open())                             
235     {                                             
236       G4ExceptionDescription ed;                  
237       ed << "G4LowEPComptonModel data file <"     
238          << "> is not opened!" << G4endl;         
239     G4Exception("G4LowEPComptonModel::ReadData    
240                 "em0003",FatalException,          
241                 ed,"G4LEDATA version should be    
242       return;                                     
243     } else {                                      
244       if(verboseLevel > 3) {                      
245         G4cout << "File " << ost.str()            
246                << " is opened by G4LowEPCompto    
247       }                                           
248       data[Z]->Retrieve(fin, true);               
249       data[Z]->ScaleVector(MeV, MeV*barn);        
250     }                                             
251   fin.close();                                    
252 }                                                 
253                                                   
254 //********************************************    
255                                                   
256                                                   
257 G4double                                          
258 G4LowEPComptonModel::ComputeCrossSectionPerAto    
259                                                   
260                                                   
261                                                   
262 {                                                 
263   if (verboseLevel > 3) {                         
264     G4cout << "G4LowEPComptonModel::ComputeCro    
265            << G4endl;                             
266   }                                               
267   G4double cs = 0.0;                              
268                                                   
269   if (GammaEnergy < LowEnergyLimit()) { return    
270                                                   
271   G4int intZ = G4lrint(Z);                        
272   if(intZ < 1 || intZ > maxZ) { return cs; }      
273                                                   
274   G4PhysicsFreeVector* pv = data[intZ];           
275                                                   
276   // if element was not initialised               
277   // do initialisation safely for MT mode         
278   if(!pv)                                         
279     {                                             
280       InitialiseForElement(0, intZ);              
281       pv = data[intZ];                            
282       if(!pv) { return cs; }                      
283     }                                             
284                                                   
285   G4int n = G4int(pv->GetVectorLength() - 1);     
286   G4double e1 = pv->Energy(0);                    
287   G4double e2 = pv->Energy(n);                    
288                                                   
289   if(GammaEnergy <= e1)      { cs = GammaEnerg    
290   else if(GammaEnergy <= e2) { cs = pv->Value(    
291   else if(GammaEnergy > e2)  { cs = pv->Value(    
292                                                   
293   return cs;                                      
294 }                                                 
295                                                   
296 //********************************************    
297                                                   
298 void G4LowEPComptonModel::SampleSecondaries(st    
299                                                   
300                                                   
301                                                   
302 {                                                 
303                                                   
304   // The scattered gamma energy is sampled acc    
305   // then accepted or rejected depending on th    
306   // by factor from Klein - Nishina formula.      
307   // Expression of the angular distribution as    
308   // angular and energy distribution and Scatt    
309   // D. E. Cullen "A simple model of photon tr    
310   // Phys. Res. B 101 (1995). Method of sampli    
311   // data are interpolated while in the articl    
312   // Reference to the article is from J. Stepa    
313   // and Electron Interaction Data for GEANT i    
314   // TeV (draft).                                 
315   // The random number techniques of Butcher &    
316   // (Nucl Phys 20(1960),15).                     
317                                                   
318   G4double photonEnergy0 = aDynamicGamma->GetK    
319                                                   
320   if (verboseLevel > 3) {                         
321     G4cout << "G4LowEPComptonModel::SampleSeco    
322            << photonEnergy0/MeV << " in " << c    
323            << G4endl;                             
324   }                                               
325   // do nothing below the threshold               
326   // should never get here because the XS is z    
327   if (photonEnergy0 < LowEnergyLimit())           
328     return ;                                      
329                                                   
330   G4double e0m = photonEnergy0 / electron_mass    
331   G4ParticleMomentum photonDirection0 = aDynam    
332                                                   
333   // Select randomly one element in the curren    
334   const G4ParticleDefinition* particle =  aDyn    
335   const G4Element* elm = SelectRandomAtom(coup    
336   G4int Z = (G4int)elm->GetZ();                   
337                                                   
338   G4double LowEPCepsilon0 = 1. / (1. + 2. * e0    
339   G4double LowEPCepsilon0Sq = LowEPCepsilon0 *    
340   G4double alpha1 = -std::log(LowEPCepsilon0);    
341   G4double alpha2 = 0.5 * (1. - LowEPCepsilon0    
342                                                   
343   G4double wlPhoton = h_Planck*c_light/photonE    
344                                                   
345   // Sample the energy of the scattered photon    
346   G4double LowEPCepsilon;                         
347   G4double LowEPCepsilonSq;                       
348   G4double oneCosT;                               
349   G4double sinT2;                                 
350   G4double gReject;                               
351                                                   
352   if (verboseLevel > 3) {                         
353     G4cout << "Started loop to sample gamma en    
354   }                                               
355                                                   
356   do                                              
357     {                                             
358       if ( alpha1/(alpha1+alpha2) > G4UniformR    
359         {                                         
360           LowEPCepsilon = G4Exp(-alpha1 * G4Un    
361           LowEPCepsilonSq = LowEPCepsilon * Lo    
362         }                                         
363       else                                        
364         {                                         
365           LowEPCepsilonSq = LowEPCepsilon0Sq +    
366           LowEPCepsilon = std::sqrt(LowEPCepsi    
367         }                                         
368                                                   
369       oneCosT = (1. - LowEPCepsilon) / ( LowEP    
370       sinT2 = oneCosT * (2. - oneCosT);           
371       G4double x = std::sqrt(oneCosT/2.) / (wl    
372       G4double scatteringFunction = ComputeSca    
373       gReject = (1. - LowEPCepsilon * sinT2 /     
374                                                   
375     } while(gReject < G4UniformRand()*Z);         
376                                                   
377   G4double cosTheta = 1. - oneCosT;               
378   G4double sinTheta = std::sqrt(sinT2);           
379   G4double phi = twopi * G4UniformRand();         
380   G4double dirx = sinTheta * std::cos(phi);       
381   G4double diry = sinTheta * std::sin(phi);       
382   G4double dirz = cosTheta ;                      
383                                                   
384   // Scatter photon energy and Compton electro    
385   // J. M. C. Brown, M. R. Dimmock, J. E. Gill    
386   // "A low energy bound atomic electron Compt    
387   // NIMB, Vol. 338, 77-88, 2014.                 
388                                                   
389   // Set constants and initialize scattering p    
390   const G4double vel_c = c_light / (m/s);         
391   const G4double momentum_au_to_nat = halfpi*     
392   const G4double e_mass_kg =  electron_mass_c2    
393                                                   
394   const G4int maxDopplerIterations = 1000;        
395   G4double bindingE = 0.;                         
396   G4double pEIncident = photonEnergy0 ;           
397   G4double pERecoil =  -1.;                       
398   G4double eERecoil = -1.;                        
399   G4double e_alpha =0.;                           
400   G4double e_beta = 0.;                           
401                                                   
402   G4double CE_emission_flag = 0.;                 
403   G4double ePAU = -1;                             
404   G4int shellIdx = 0;                             
405   G4double u_temp = 0;                            
406   G4double cosPhiE =0;                            
407   G4double sinThetaE =0;                          
408   G4double cosThetaE =0;                          
409   G4int iteration = 0;                            
410                                                   
411   if (verboseLevel > 3) {                         
412     G4cout << "Started loop to sample photon e    
413   }                                               
414                                                   
415   do{                                             
416       // *************************************    
417       // |     Determine scatter photon energy    
418       // *************************************    
419     do                                            
420       {                                           
421   iteration++;                                    
422   // *****************************************    
423   // |     Sample bound electron information      
424   // *****************************************    
425                                                   
426   // Select shell based on shell occupancy        
427   shellIdx = shellData->SelectRandomShell(Z);     
428   bindingE = shellData->BindingEnergy(Z,shellI    
429                                                   
430   // Randomly sample bound electron momentum (    
431   ePAU = profileData->RandomSelectMomentum(Z,s    
432                                                   
433   // Convert to SI units                          
434   G4double ePSI = ePAU * momentum_au_to_nat;      
435                                                   
436   //Calculate bound electron velocity and norm    
437   u_temp = sqrt( ((ePSI*ePSI)*(vel_c*vel_c)) /    
438                                                   
439   // Sample incident electron direction, amorp    
440   e_alpha = pi*G4UniformRand();                   
441   e_beta = twopi*G4UniformRand();                 
442                                                   
443   // Total energy of system                       
444                                                   
445   G4double eEIncident = electron_mass_c2 / sqr    
446   G4double systemE = eEIncident + pEIncident;     
447   G4double gamma_temp = 1.0 / sqrt( 1 - (u_tem    
448   G4double numerator = gamma_temp*electron_mas    
449   G4double subdenom1 =  u_temp*cosTheta*std::c    
450   G4double subdenom2 = u_temp*sinTheta*std::si    
451   G4double denominator = (1.0 - cosTheta) +  (    
452   pERecoil = (numerator/denominator);             
453   eERecoil = systemE - pERecoil;                  
454   CE_emission_flag = pEIncident - pERecoil;       
455       } while ( (iteration <= maxDopplerIterat    
456                                                   
457     // End of recalculation of photon energy w    
458                                                   
459     // ***************************************    
460     // |     Determine ejected Compton electro    
461     // ***************************************    
462                                                   
463     // Calculate velocity of ejected Compton e    
464                                                   
465     G4double a_temp = eERecoil / electron_mass    
466     G4double u_p_temp = sqrt(1 - (1 / (a_temp*    
467                                                   
468     // Coefficients and terms from simulatenou    
469     G4double sinAlpha = std::sin(e_alpha);        
470     G4double cosAlpha = std::cos(e_alpha);        
471     G4double sinBeta = std::sin(e_beta);          
472     G4double cosBeta = std::cos(e_beta);          
473                                                   
474     G4double gamma = 1.0 / sqrt(1 - (u_temp*u_    
475     G4double gamma_p = 1.0 / sqrt(1 - (u_p_tem    
476                                                   
477     G4double var_A = pERecoil*u_p_temp*sinThet    
478     G4double var_B = u_p_temp* (pERecoil*cosTh    
479     G4double var_C = (pERecoil-pEIncident) - (    
480                                                   
481     G4double var_D1 = gamma*electron_mass_c2*p    
482     G4double var_D2 = (1 - (u_temp*cosTheta*co    
483     G4double var_D3 = ((electron_mass_c2*elect    
484     G4double var_D = var_D1*var_D2 + var_D3;      
485                                                   
486     G4double var_E1 = ((gamma*gamma_p)*(electr    
487     G4double var_E2 = gamma_p*electron_mass_c2    
488     G4double var_E = var_E1 - var_E2;             
489                                                   
490     G4double var_F1 = ((gamma*gamma_p)*(electr    
491     G4double var_F2 = (gamma_p*electron_mass_c    
492     G4double var_F = var_F1 - var_F2;             
493                                                   
494     G4double var_G = (gamma*gamma_p)*(electron    
495                                                   
496     // Two equations form a quadratic form of     
497     // Coefficents and solution to quadratic      
498     G4double var_W1 = (var_F*var_B - var_E*var    
499     G4double var_W2 = (var_G*var_G)*(var_A*var    
500     G4double var_W = var_W1 + var_W2;             
501                                                   
502     G4double var_Y = 2.0*(((var_A*var_D-var_F*    
503                                                   
504     G4double var_Z1 = (var_A*var_D - var_F*var    
505     G4double var_Z2 = (var_G*var_G)*(var_C*var    
506     G4double var_Z = var_Z1 + var_Z2;             
507     G4double diff1 = var_Y*var_Y;                 
508     G4double diff2 = 4*var_W*var_Z;               
509     G4double diff = diff1 - diff2;                
510                                                   
511     // Check if diff is less than zero, if so     
512     //Determine number of digits (in decimal b    
513     G4double g4d_order = G4double(numeric_limi    
514     G4double g4d_limit = std::pow(10.,-g4d_ord    
515     //Confirm that diff less than zero is due     
516     //than 10^(-g4d_order), then set diff to z    
517                                                   
518     if ((diff < 0.0) && (abs(diff / diff1) < g    
519       {                                           
520   diff = 0.0;                                     
521       }                                           
522                                                   
523                                                   
524     // Plus and minus of quadratic                
525     G4double X_p = (-var_Y + sqrt (diff))/(2*v    
526     G4double X_m = (-var_Y - sqrt (diff))/(2*v    
527                                                   
528     // Floating point precision protection        
529     // Check if X_p and X_m are greater than o    
530     // Issue due to propagation of FPE and onl    
531     if(X_p >1){X_p=1;} if(X_p<-1){X_p=-1;}        
532     if(X_m >1){X_m=1;} if(X_m<-1){X_m=-1;}        
533     // End of FP protection                       
534                                                   
535     G4double ThetaE = 0.;                         
536     // Randomly sample one of the two possible    
537     G4double sol_select = G4UniformRand();        
538                                                   
539     if (sol_select < 0.5)                         
540       {                                           
541   ThetaE = std::acos(X_p);                        
542       }                                           
543     if (sol_select > 0.5)                         
544       {                                           
545   ThetaE = std::acos(X_m);                        
546       }                                           
547     cosThetaE = std::cos(ThetaE);                 
548     sinThetaE = std::sin(ThetaE);                 
549     G4double Theta = std::acos(cosTheta);         
550                                                   
551     //Calculate electron Phi                      
552     G4double iSinThetaE = std::sqrt(1+std::tan    
553     G4double iSinTheta = std::sqrt(1+std::tan(    
554     G4double ivar_A = iSinTheta/ (pERecoil*u_p    
555     // Trigs                                      
556     cosPhiE = (var_C - var_B*cosThetaE)*(ivar_    
557                                                   
558     // End of calculation of ejection Compton     
559     //Fix for floating point errors               
560                                                   
561   } while ( (iteration <= maxDopplerIterations    
562                                                   
563   // Revert to original if maximum number of i    
564   if (iteration >= maxDopplerIterations)          
565     {                                             
566       pERecoil = photonEnergy0 ;                  
567       bindingE = 0.;                              
568       dirx=0.0;                                   
569       diry=0.0;                                   
570       dirz=1.0;                                   
571     }                                             
572                                                   
573   // Set "scattered" photon direction and ener    
574   G4ThreeVector photonDirection1(dirx,diry,dir    
575   photonDirection1.rotateUz(photonDirection0);    
576   fParticleChange->ProposeMomentumDirection(ph    
577                                                   
578   if (pERecoil > 0.)                              
579     {                                             
580      fParticleChange->SetProposedKineticEnergy    
581                                                   
582      // Set ejected Compton electron direction    
583      G4double PhiE = std::acos(cosPhiE);          
584      G4double eDirX = sinThetaE * std::cos(phi    
585      G4double eDirY = sinThetaE * std::sin(phi    
586      G4double eDirZ = cosThetaE;                  
587                                                   
588      G4double eKineticEnergy = pEIncident - pE    
589                                                   
590      G4ThreeVector eDirection(eDirX,eDirY,eDir    
591      eDirection.rotateUz(photonDirection0);       
592      G4DynamicParticle* dp = new G4DynamicPart    
593                                                   
594      fvect->push_back(dp);                        
595                                                   
596     }                                             
597   else                                            
598     {                                             
599       fParticleChange->SetProposedKineticEnerg    
600       fParticleChange->ProposeTrackStatus(fSto    
601     }                                             
602                                                   
603   // sample deexcitation                          
604   //                                              
605   if (verboseLevel > 3) {                         
606     G4cout << "Started atomic de-excitation "     
607   }                                               
608                                                   
609   if(fAtomDeexcitation && iteration < maxDoppl    
610     G4int index = couple->GetIndex();             
611     if(fAtomDeexcitation->CheckDeexcitationAct    
612       std::size_t nbefore = fvect->size();        
613       G4AtomicShellEnumerator as = G4AtomicShe    
614       const G4AtomicShell* shell = fAtomDeexci    
615       fAtomDeexcitation->GenerateParticles(fve    
616       std::size_t nafter = fvect->size();         
617       if(nafter > nbefore) {                      
618         for (std::size_t i=nbefore; i<nafter;     
619           //Check if there is enough residual     
620           if (bindingE >= ((*fvect)[i])->GetKi    
621            {                                      
622              //Ok, this is a valid secondary:     
623              bindingE -= ((*fvect)[i])->GetKin    
624            }                                      
625           else                                    
626            {                                      
627              //Invalid secondary: not enough e    
628              //Keep its energy in the local de    
629              delete (*fvect)[i];                  
630              (*fvect)[i]=nullptr;                 
631            }                                      
632         }                                         
633       }                                           
634     }                                             
635   }                                               
636                                                   
637   //This should never happen                      
638   if(bindingE < 0.0)                              
639      G4Exception("G4LowEPComptonModel::SampleS    
640                  "em2051",FatalException,"Nega    
641                                                   
642   fParticleChange->ProposeLocalEnergyDeposit(b    
643 }                                                 
644                                                   
645 //********************************************    
646                                                   
647 G4double                                          
648 G4LowEPComptonModel::ComputeScatteringFunction    
649 {                                                 
650   G4double value = Z;                             
651   if (x <= ScatFuncFitParam[Z][2]) {              
652                                                   
653     G4double lgq = G4Log(x)/ln10;                 
654                                                   
655     if (lgq < ScatFuncFitParam[Z][1]) {           
656       value = ScatFuncFitParam[Z][3] + lgq*Sca    
657     } else {                                      
658       value = ScatFuncFitParam[Z][5] + lgq*Sca    
659         lgq*lgq*ScatFuncFitParam[Z][7] + lgq*l    
660     }                                             
661     value = G4Exp(value*ln10);                    
662   }                                               
663   return value;                                   
664 }                                                 
665                                                   
666                                                   
667 //********************************************    
668                                                   
669 void                                              
670 G4LowEPComptonModel::InitialiseForElement(cons    
671                                                   
672 {                                                 
673   G4AutoLock l(&LowEPComptonModelMutex);          
674   if(!data[Z]) { ReadData(Z); }                   
675   l.unlock();                                     
676 }                                                 
677                                                   
678 //********************************************    
679                                                   
680 //Fitting data to compute scattering function     
681                                                   
682 const G4double G4LowEPComptonModel::ScatFuncFi    
683 {  0,    0.,          0.,      0.,    0.,         
684 {  1, 6.673, 1.49968E+08, -14.352, 1.999, -143    
685 {  2, 6.500, 2.50035E+08, -14.215, 1.970, -53.    
686 {  3, 6.551, 3.99945E+08, -13.555, 1.993, -62.    
687 {  4, 6.500, 5.00035E+08, -13.746, 1.998, -127    
688 {  5, 6.500, 5.99791E+08, -13.800, 1.998, -131    
689 {  6, 6.708, 6.99842E+08, -13.885, 1.999, -128    
690 {  7, 6.685, 7.99834E+08, -13.885, 2.000, -131    
691 {  8, 6.669, 7.99834E+08, -13.962, 2.001, -128    
692 {  9, 6.711, 7.99834E+08, -13.999, 2.000, -122    
693 { 10, 6.702, 7.99834E+08, -14.044, 1.999, -110    
694 { 11, 6.425, 1.00000E+09, -13.423, 1.993, -41.    
695 { 12, 6.542, 1.00000E+09, -13.389, 1.997, -53.    
696 { 13, 6.570, 1.49968E+09, -13.401, 1.997, -66.    
697 { 14, 6.364, 1.49968E+09, -13.452, 1.999, -78.    
698 { 15, 6.500, 1.49968E+09, -13.488, 1.998, -85.    
699 { 16, 6.500, 1.49968E+09, -13.532, 1.998, -93.    
700 { 17, 6.500, 1.49968E+09, -13.584, 2.000, -98.    
701 { 18, 6.500, 1.49968E+09, -13.618, 1.999, -100    
702 { 19, 6.500, 1.99986E+09, -13.185, 1.992, -53.    
703 { 20, 6.490, 1.99986E+09, -13.123, 1.993, -52.    
704 { 21, 6.498, 1.99986E+09, -13.157, 1.994, -55.    
705 { 22, 6.495, 1.99986E+09, -13.183, 1.994, -57.    
706 { 23, 6.487, 1.99986E+09, -13.216, 1.995, -58.    
707 { 24, 6.500, 1.99986E+09, -13.330, 1.997, -62.    
708 { 25, 6.488, 1.99986E+09, -13.277, 1.997, -58.    
709 { 26, 6.500, 5.00035E+09, -13.292, 1.997, -61.    
710 { 27, 6.500, 5.00035E+09, -13.321, 1.998, -61.    
711 { 28, 6.500, 5.00035E+09, -13.340, 1.998, -62.    
712 { 29, 6.500, 5.00035E+09, -13.439, 1.998, -67.    
713 { 30, 6.500, 5.00035E+09, -13.383, 1.999, -62.    
714 { 31, 6.500, 5.00035E+09, -13.349, 1.997, -61.    
715 { 32, 6.500, 5.00035E+09, -13.373, 1.999, -63.    
716 { 33, 6.500, 5.00035E+09, -13.395, 1.999, -65.    
717 { 34, 6.500, 5.00035E+09, -13.417, 1.999, -69.    
718 { 35, 6.500, 5.00035E+09, -13.442, 2.000, -72.    
719 { 36, 6.500, 5.00035E+09, -13.451, 1.998, -74.    
720 { 37, 6.500, 5.00035E+09, -13.082, 1.991, -46.    
721 { 38, 6.465, 5.00035E+09, -13.022, 1.993, -41.    
722 { 39, 6.492, 5.00035E+09, -13.043, 1.994, -44.    
723 { 40, 6.499, 5.00035E+09, -13.064, 1.994, -47.    
724 { 41, 6.384, 5.00035E+09, -13.156, 1.996, -53.    
725 { 42, 6.500, 5.00035E+09, -13.176, 1.996, -54.    
726 { 43, 6.500, 5.00035E+09, -13.133, 1.997, -51.    
727 { 44, 6.500, 5.00035E+09, -13.220, 1.996, -58.    
728 { 45, 6.500, 5.00035E+09, -13.246, 1.998, -59.    
729 { 46, 6.500, 5.00035E+09, -13.407, 1.999, -72.    
730 { 47, 6.500, 5.00035E+09, -13.277, 1.998, -60.    
731 { 48, 6.500, 5.00035E+09, -13.222, 1.998, -56.    
732 { 49, 6.500, 5.00035E+09, -13.199, 1.997, -56.    
733 { 50, 6.500, 5.00035E+09, -13.215, 1.998, -58.    
734 { 51, 6.500, 5.00035E+09, -13.230, 1.998, -60.    
735 { 52, 6.500, 7.99834E+09, -13.246, 1.998, -63.    
736 { 53, 6.500, 5.00035E+09, -13.262, 1.998, -66.    
737 { 54, 6.500, 7.99834E+09, -13.279, 1.998, -67.    
738 { 55, 6.500, 5.00035E+09, -12.951, 1.990, -45.    
739 { 56, 6.425, 5.00035E+09, -12.882, 1.992, -39.    
740 { 57, 6.466, 2.82488E+09, -12.903, 1.992, -38.    
741 { 58, 6.451, 5.00035E+09, -12.915, 1.993, -41.    
742 { 59, 6.434, 5.00035E+09, -12.914, 1.993, -40.    
743 { 60, 6.444, 5.00035E+09, -12.922, 1.992, -39.    
744 { 61, 6.414, 7.99834E+09, -12.930, 1.993, -42.    
745 { 62, 6.420, 7.99834E+09, -12.938, 1.992, -42.    
746 { 63, 6.416, 7.99834E+09, -12.946, 1.993, -42.    
747 { 64, 6.443, 7.99834E+09, -12.963, 1.993, -43.    
748 { 65, 6.449, 7.99834E+09, -12.973, 1.993, -43.    
749 { 66, 6.419, 7.99834E+09, -12.966, 1.993, -42.    
750 { 67, 6.406, 7.99834E+09, -12.976, 1.993, -42.    
751 { 68, 6.424, 7.99834E+09, -12.986, 1.993, -41.    
752 { 69, 6.417, 7.99834E+09, -12.989, 1.993, -42.    
753 { 70, 6.405, 7.99834E+09, -13.000, 1.994, -42.    
754 { 71, 6.449, 7.99834E+09, -13.015, 1.994, -42.    
755 { 72, 6.465, 7.99834E+09, -13.030, 1.994, -43.    
756 { 73, 6.447, 7.99834E+09, -13.048, 1.996, -44.    
757 { 74, 6.452, 7.99834E+09, -13.073, 1.997, -45.    
758 { 75, 6.432, 7.99834E+09, -13.082, 1.997, -46.    
759 { 76, 6.439, 7.99834E+09, -13.100, 1.997, -47.    
760 { 77, 6.432, 7.99834E+09, -13.110, 1.997, -48.    
761 { 78, 6.500, 7.99834E+09, -13.185, 1.997, -53.    
762 { 79, 6.500, 7.99834E+09, -13.200, 1.997, -53.    
763 { 80, 6.500, 7.99834E+09, -13.156, 1.998, -49.    
764 { 81, 6.500, 7.99834E+09, -13.128, 1.997, -49.    
765 { 82, 6.500, 7.99834E+09, -13.134, 1.997, -51.    
766 { 83, 6.500, 7.99834E+09, -13.148, 1.998, -52.    
767 { 84, 6.500, 7.99834E+09, -13.161, 1.998, -54.    
768 { 85, 6.500, 7.99834E+09, -13.175, 1.998, -56.    
769 { 86, 6.500, 7.99834E+09, -13.189, 1.998, -57.    
770 { 87, 6.500, 7.99834E+09, -12.885, 1.990, -39.    
771 { 88, 6.417, 7.99834E+09, -12.816, 1.991, -34.    
772 { 89, 6.442, 7.99834E+09, -12.831, 1.992, -36.    
773 { 90, 6.463, 7.99834E+09, -12.850, 1.993, -37.    
774 { 91, 6.447, 7.99834E+09, -12.852, 1.993, -37.    
775 { 92, 6.439, 7.99834E+09, -12.858, 1.993, -37.    
776 { 93, 6.437, 1.00000E+10, -12.866, 1.993, -39.    
777 { 94, 6.432, 7.99834E+09, -12.862, 1.993, -37.    
778 { 95, 6.435, 7.99834E+09, -12.869, 1.993, -37.    
779 { 96, 6.449, 1.00000E+10, -12.886, 1.993, -39.    
780 { 97, 6.446, 1.00000E+10, -12.892, 1.993, -40.    
781 { 98, 6.421, 1.00000E+10, -12.887, 1.993, -39.    
782 { 99, 6.414, 1.00000E+10, -12.894, 1.993, -39.    
783 {100, 6.412, 1.00000E+10, -12.900, 1.993, -39.    
784   };                                              
785                                                   
786                                                   
787                                                   
788