1 | // |
---|
2 | // ******************************************************************** |
---|
3 | // * License and Disclaimer * |
---|
4 | // * * |
---|
5 | // * The Geant4 software is copyright of the Copyright Holders of * |
---|
6 | // * the Geant4 Collaboration. It is provided under the terms and * |
---|
7 | // * conditions of the Geant4 Software License, included in the file * |
---|
8 | // * LICENSE and available at http://cern.ch/geant4/license . These * |
---|
9 | // * include a list of copyright holders. * |
---|
10 | // * * |
---|
11 | // * Neither the authors of this software system, nor their employing * |
---|
12 | // * institutes,nor the agencies providing financial support for this * |
---|
13 | // * work make any representation or warranty, express or implied, * |
---|
14 | // * regarding this software system or assume any liability for its * |
---|
15 | // * use. Please see the license in the file LICENSE and URL above * |
---|
16 | // * for the full disclaimer and the limitation of liability. * |
---|
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 * |
---|
21 | // * any work based on the software) you agree to acknowledge its * |
---|
22 | // * use in resulting scientific publications, and indicate your * |
---|
23 | // * acceptance of all terms of the Geant4 Software license. * |
---|
24 | // ******************************************************************** |
---|
25 | // |
---|
26 | // |
---|
27 | // |
---|
28 | // $Id: G4GeneralSpaceDecay.cc,v 1.0 1998/05/21 |
---|
29 | // ---------------------------------------------------------------- |
---|
30 | // GEANT 4 class header file |
---|
31 | // |
---|
32 | // History: first implementation, A. Feliciello, 21st May 1998 |
---|
33 | // |
---|
34 | // Note: this class is a generalization of the |
---|
35 | // G4PhaseSpaceDecayChannel one |
---|
36 | // ---------------------------------------------------------------- |
---|
37 | |
---|
38 | #include "G4ParticleDefinition.hh" |
---|
39 | #include "G4DecayProducts.hh" |
---|
40 | #include "G4VDecayChannel.hh" |
---|
41 | #include "G4GeneralPhaseSpaceDecay.hh" |
---|
42 | #include "Randomize.hh" |
---|
43 | #include "G4LorentzVector.hh" |
---|
44 | #include "G4LorentzRotation.hh" |
---|
45 | #include "G4ios.hh" |
---|
46 | |
---|
47 | |
---|
48 | G4GeneralPhaseSpaceDecay::G4GeneralPhaseSpaceDecay(G4int Verbose) : |
---|
49 | G4VDecayChannel("Phase Space", Verbose), |
---|
50 | theDaughterMasses(0) |
---|
51 | { |
---|
52 | if (GetVerboseLevel()>1) G4cout << "G4GeneralPhaseSpaceDecay:: constructor " << G4endl; |
---|
53 | } |
---|
54 | |
---|
55 | G4GeneralPhaseSpaceDecay::G4GeneralPhaseSpaceDecay(const G4String& theParentName, |
---|
56 | G4double theBR, |
---|
57 | G4int theNumberOfDaughters, |
---|
58 | const G4String& theDaughterName1, |
---|
59 | const G4String& theDaughterName2, |
---|
60 | const G4String& theDaughterName3) : |
---|
61 | G4VDecayChannel("Phase Space", |
---|
62 | theParentName,theBR, |
---|
63 | theNumberOfDaughters, |
---|
64 | theDaughterName1, |
---|
65 | theDaughterName2, |
---|
66 | theDaughterName3), |
---|
67 | theDaughterMasses(0) |
---|
68 | { |
---|
69 | if (GetVerboseLevel()>1) G4cout << "G4GeneralPhaseSpaceDecay:: constructor " << G4endl; |
---|
70 | |
---|
71 | // Set the parent particle (resonance) mass to the (default) PDG vale |
---|
72 | if (parent != NULL) |
---|
73 | { |
---|
74 | parentmass = parent->GetPDGMass(); |
---|
75 | } |
---|
76 | } |
---|
77 | |
---|
78 | G4GeneralPhaseSpaceDecay::G4GeneralPhaseSpaceDecay(const G4String& theParentName, |
---|
79 | G4double theParentMass, |
---|
80 | G4double theBR, |
---|
81 | G4int theNumberOfDaughters, |
---|
82 | const G4String& theDaughterName1, |
---|
83 | const G4String& theDaughterName2, |
---|
84 | const G4String& theDaughterName3) : |
---|
85 | G4VDecayChannel("Phase Space", |
---|
86 | theParentName,theBR, |
---|
87 | theNumberOfDaughters, |
---|
88 | theDaughterName1, |
---|
89 | theDaughterName2, |
---|
90 | theDaughterName3), |
---|
91 | parentmass(theParentMass), |
---|
92 | theDaughterMasses(0) |
---|
93 | { |
---|
94 | if (GetVerboseLevel()>1) G4cout << "G4GeneralPhaseSpaceDecay:: constructor " << G4endl; |
---|
95 | } |
---|
96 | |
---|
97 | G4GeneralPhaseSpaceDecay::G4GeneralPhaseSpaceDecay(const G4String& theParentName, |
---|
98 | G4double theParentMass, |
---|
99 | G4double theBR, |
---|
100 | G4int theNumberOfDaughters, |
---|
101 | const G4String& theDaughterName1, |
---|
102 | const G4String& theDaughterName2, |
---|
103 | const G4String& theDaughterName3, |
---|
104 | const G4double *masses) : |
---|
105 | G4VDecayChannel("Phase Space", |
---|
106 | theParentName,theBR, |
---|
107 | theNumberOfDaughters, |
---|
108 | theDaughterName1, |
---|
109 | theDaughterName2, |
---|
110 | theDaughterName3), |
---|
111 | parentmass(theParentMass), |
---|
112 | theDaughterMasses(masses) |
---|
113 | { |
---|
114 | if (GetVerboseLevel()>1) G4cout << "G4GeneralPhaseSpaceDecay:: constructor " << G4endl; |
---|
115 | } |
---|
116 | |
---|
117 | G4GeneralPhaseSpaceDecay::~G4GeneralPhaseSpaceDecay() |
---|
118 | { |
---|
119 | } |
---|
120 | |
---|
121 | G4DecayProducts *G4GeneralPhaseSpaceDecay::DecayIt(G4double) |
---|
122 | { |
---|
123 | if (GetVerboseLevel()>1) G4cout << "G4GeneralPhaseSpaceDecay::DecayIt "; |
---|
124 | G4DecayProducts * products = NULL; |
---|
125 | |
---|
126 | if (parent == NULL) FillParent(); |
---|
127 | if (daughters == NULL) FillDaughters(); |
---|
128 | |
---|
129 | switch (numberOfDaughters){ |
---|
130 | case 0: |
---|
131 | if (GetVerboseLevel()>0) { |
---|
132 | G4cout << "G4GeneralPhaseSpaceDecay::DecayIt "; |
---|
133 | G4cout << " daughters not defined " <<G4endl; |
---|
134 | } |
---|
135 | break; |
---|
136 | case 1: |
---|
137 | products = OneBodyDecayIt(); |
---|
138 | break; |
---|
139 | case 2: |
---|
140 | products = TwoBodyDecayIt(); |
---|
141 | break; |
---|
142 | case 3: |
---|
143 | products = ThreeBodyDecayIt(); |
---|
144 | break; |
---|
145 | default: |
---|
146 | products = ManyBodyDecayIt(); |
---|
147 | break; |
---|
148 | } |
---|
149 | if ((products == NULL) && (GetVerboseLevel()>0)) { |
---|
150 | G4cout << "G4GeneralPhaseSpaceDecay::DecayIt "; |
---|
151 | G4cout << *parent_name << " can not decay " << G4endl; |
---|
152 | DumpInfo(); |
---|
153 | } |
---|
154 | return products; |
---|
155 | } |
---|
156 | |
---|
157 | G4DecayProducts *G4GeneralPhaseSpaceDecay::OneBodyDecayIt() |
---|
158 | { |
---|
159 | if (GetVerboseLevel()>1) G4cout << "G4GeneralPhaseSpaceDecay::OneBodyDecayIt()"<<G4endl; |
---|
160 | |
---|
161 | // G4double daughtermass = daughters[0]->GetPDGMass(); |
---|
162 | |
---|
163 | //create parent G4DynamicParticle at rest |
---|
164 | G4ParticleMomentum dummy; |
---|
165 | G4DynamicParticle * parentparticle = new G4DynamicParticle(parent, dummy, 0.0); |
---|
166 | |
---|
167 | //create G4Decayproducts |
---|
168 | G4DecayProducts *products = new G4DecayProducts(*parentparticle); |
---|
169 | delete parentparticle; |
---|
170 | |
---|
171 | //create daughter G4DynamicParticle at rest |
---|
172 | G4DynamicParticle * daughterparticle = new G4DynamicParticle(daughters[0], dummy, 0.0); |
---|
173 | products->PushProducts(daughterparticle); |
---|
174 | |
---|
175 | if (GetVerboseLevel()>1) |
---|
176 | { |
---|
177 | G4cout << "G4GeneralPhaseSpaceDecay::OneBodyDecayIt "; |
---|
178 | G4cout << " create decay products in rest frame " <<G4endl; |
---|
179 | products->DumpInfo(); |
---|
180 | } |
---|
181 | return products; |
---|
182 | } |
---|
183 | |
---|
184 | G4DecayProducts *G4GeneralPhaseSpaceDecay::TwoBodyDecayIt() |
---|
185 | { |
---|
186 | if (GetVerboseLevel()>1) G4cout << "G4GeneralPhaseSpaceDecay::TwoBodyDecayIt()"<<G4endl; |
---|
187 | |
---|
188 | //daughters'mass |
---|
189 | G4double daughtermass[2]; |
---|
190 | G4double daughtermomentum; |
---|
191 | if ( theDaughterMasses ) |
---|
192 | { |
---|
193 | daughtermass[0]= *(theDaughterMasses); |
---|
194 | daughtermass[1] = *(theDaughterMasses+1); |
---|
195 | } else { |
---|
196 | daughtermass[0] = daughters[0]->GetPDGMass(); |
---|
197 | daughtermass[1] = daughters[1]->GetPDGMass(); |
---|
198 | } |
---|
199 | |
---|
200 | // G4double sumofdaughtermass = daughtermass[0] + daughtermass[1]; |
---|
201 | |
---|
202 | //create parent G4DynamicParticle at rest |
---|
203 | G4ParticleMomentum dummy; |
---|
204 | G4DynamicParticle * parentparticle = new G4DynamicParticle( parent, dummy, 0.0); |
---|
205 | |
---|
206 | //create G4Decayproducts @@GF why dummy parentparticle? |
---|
207 | G4DecayProducts *products = new G4DecayProducts(*parentparticle); |
---|
208 | delete parentparticle; |
---|
209 | |
---|
210 | //calculate daughter momentum |
---|
211 | daughtermomentum = Pmx(parentmass,daughtermass[0],daughtermass[1]); |
---|
212 | G4double costheta = 2.*G4UniformRand()-1.0; |
---|
213 | G4double sintheta = std::sqrt((1.0 - costheta)*(1.0 + costheta)); |
---|
214 | G4double phi = twopi*G4UniformRand()*rad; |
---|
215 | G4ParticleMomentum direction(sintheta*std::cos(phi),sintheta*std::sin(phi),costheta); |
---|
216 | |
---|
217 | //create daughter G4DynamicParticle |
---|
218 | G4double Etotal= std::sqrt(daughtermass[0]*daughtermass[0] + daughtermomentum*daughtermomentum); |
---|
219 | G4DynamicParticle * daughterparticle = new G4DynamicParticle( daughters[0],Etotal, direction*daughtermomentum); |
---|
220 | products->PushProducts(daughterparticle); |
---|
221 | Etotal= std::sqrt(daughtermass[1]*daughtermass[1] + daughtermomentum*daughtermomentum); |
---|
222 | daughterparticle = new G4DynamicParticle( daughters[1],Etotal, direction*(-1.0*daughtermomentum)); |
---|
223 | products->PushProducts(daughterparticle); |
---|
224 | |
---|
225 | if (GetVerboseLevel()>1) |
---|
226 | { |
---|
227 | G4cout << "G4GeneralPhaseSpaceDecay::TwoBodyDecayIt "; |
---|
228 | G4cout << " create decay products in rest frame " <<G4endl; |
---|
229 | products->DumpInfo(); |
---|
230 | } |
---|
231 | return products; |
---|
232 | } |
---|
233 | |
---|
234 | G4DecayProducts *G4GeneralPhaseSpaceDecay::ThreeBodyDecayIt() |
---|
235 | // algorism of this code is originally written in GDECA3 of GEANT3 |
---|
236 | { |
---|
237 | if (GetVerboseLevel()>1) G4cout << "G4GeneralPhaseSpaceDecay::ThreeBodyDecayIt()"<<G4endl; |
---|
238 | |
---|
239 | //daughters'mass |
---|
240 | G4double daughtermass[3]; |
---|
241 | G4double sumofdaughtermass = 0.0; |
---|
242 | for (G4int index=0; index<3; index++) |
---|
243 | { |
---|
244 | if ( theDaughterMasses ) |
---|
245 | { |
---|
246 | daughtermass[index]= *(theDaughterMasses+index); |
---|
247 | } else { |
---|
248 | daughtermass[index] = daughters[index]->GetPDGMass(); |
---|
249 | } |
---|
250 | sumofdaughtermass += daughtermass[index]; |
---|
251 | } |
---|
252 | |
---|
253 | //create parent G4DynamicParticle at rest |
---|
254 | G4ParticleMomentum dummy; |
---|
255 | G4DynamicParticle * parentparticle = new G4DynamicParticle( parent, dummy, 0.0); |
---|
256 | |
---|
257 | //create G4Decayproducts |
---|
258 | G4DecayProducts *products = new G4DecayProducts(*parentparticle); |
---|
259 | delete parentparticle; |
---|
260 | |
---|
261 | //calculate daughter momentum |
---|
262 | // Generate two |
---|
263 | G4double rd1, rd2, rd; |
---|
264 | G4double daughtermomentum[3]; |
---|
265 | G4double momentummax=0.0, momentumsum = 0.0; |
---|
266 | G4double energy; |
---|
267 | |
---|
268 | do |
---|
269 | { |
---|
270 | rd1 = G4UniformRand(); |
---|
271 | rd2 = G4UniformRand(); |
---|
272 | if (rd2 > rd1) |
---|
273 | { |
---|
274 | rd = rd1; |
---|
275 | rd1 = rd2; |
---|
276 | rd2 = rd; |
---|
277 | } |
---|
278 | momentummax = 0.0; |
---|
279 | momentumsum = 0.0; |
---|
280 | // daughter 0 |
---|
281 | |
---|
282 | energy = rd2*(parentmass - sumofdaughtermass); |
---|
283 | daughtermomentum[0] = std::sqrt(energy*energy + 2.0*energy* daughtermass[0]); |
---|
284 | if ( daughtermomentum[0] >momentummax )momentummax = daughtermomentum[0]; |
---|
285 | momentumsum += daughtermomentum[0]; |
---|
286 | |
---|
287 | // daughter 1 |
---|
288 | energy = (1.-rd1)*(parentmass - sumofdaughtermass); |
---|
289 | daughtermomentum[1] = std::sqrt(energy*energy + 2.0*energy* daughtermass[1]); |
---|
290 | if ( daughtermomentum[1] >momentummax )momentummax = daughtermomentum[1]; |
---|
291 | momentumsum += daughtermomentum[1]; |
---|
292 | |
---|
293 | // daughter 2 |
---|
294 | energy = (rd1-rd2)*(parentmass - sumofdaughtermass); |
---|
295 | daughtermomentum[2] = std::sqrt(energy*energy + 2.0*energy* daughtermass[2]); |
---|
296 | if ( daughtermomentum[2] >momentummax )momentummax = daughtermomentum[2]; |
---|
297 | momentumsum += daughtermomentum[2]; |
---|
298 | } while (momentummax > momentumsum - momentummax ); |
---|
299 | |
---|
300 | // output message |
---|
301 | if (GetVerboseLevel()>1) { |
---|
302 | G4cout << " daughter 0:" << daughtermomentum[0]/GeV << "[GeV/c]" <<G4endl; |
---|
303 | G4cout << " daughter 1:" << daughtermomentum[1]/GeV << "[GeV/c]" <<G4endl; |
---|
304 | G4cout << " daughter 2:" << daughtermomentum[2]/GeV << "[GeV/c]" <<G4endl; |
---|
305 | G4cout << " momentum sum:" << momentumsum/GeV << "[GeV/c]" <<G4endl; |
---|
306 | } |
---|
307 | |
---|
308 | //create daughter G4DynamicParticle |
---|
309 | G4double costheta, sintheta, phi, sinphi, cosphi; |
---|
310 | G4double costhetan, sinthetan, phin, sinphin, cosphin; |
---|
311 | costheta = 2.*G4UniformRand()-1.0; |
---|
312 | sintheta = std::sqrt((1.0-costheta)*(1.0+costheta)); |
---|
313 | phi = twopi*G4UniformRand()*rad; |
---|
314 | sinphi = std::sin(phi); |
---|
315 | cosphi = std::cos(phi); |
---|
316 | G4ParticleMomentum direction0(sintheta*cosphi,sintheta*sinphi,costheta); |
---|
317 | G4double Etotal=std::sqrt( daughtermass[0]*daughtermass[0] + daughtermomentum[0]*daughtermomentum[0]); |
---|
318 | G4DynamicParticle * daughterparticle |
---|
319 | = new G4DynamicParticle( daughters[0], Etotal, direction0*daughtermomentum[0]); |
---|
320 | products->PushProducts(daughterparticle); |
---|
321 | |
---|
322 | costhetan = (daughtermomentum[1]*daughtermomentum[1]-daughtermomentum[2]*daughtermomentum[2]-daughtermomentum[0]*daughtermomentum[0])/(2.0*daughtermomentum[2]*daughtermomentum[0]); |
---|
323 | sinthetan = std::sqrt((1.0-costhetan)*(1.0+costhetan)); |
---|
324 | phin = twopi*G4UniformRand()*rad; |
---|
325 | sinphin = std::sin(phin); |
---|
326 | cosphin = std::cos(phin); |
---|
327 | G4ParticleMomentum direction2; |
---|
328 | direction2.setX( sinthetan*cosphin*costheta*cosphi - sinthetan*sinphin*sinphi + costhetan*sintheta*cosphi); |
---|
329 | direction2.setY( sinthetan*cosphin*costheta*sinphi + sinthetan*sinphin*cosphi + costhetan*sintheta*sinphi); |
---|
330 | direction2.setZ( -sinthetan*cosphin*sintheta + costhetan*costheta); |
---|
331 | Etotal=std::sqrt( daughtermass[2]*daughtermass[2] + daughtermomentum[2]*daughtermomentum[2]/direction2.mag2()); |
---|
332 | daughterparticle = new G4DynamicParticle( daughters[2],Etotal, direction2*(daughtermomentum[2]/direction2.mag())); |
---|
333 | products->PushProducts(daughterparticle); |
---|
334 | G4ThreeVector mom=(direction0*daughtermomentum[0] + direction2*(daughtermomentum[2]/direction2.mag()))*(-1.0); |
---|
335 | Etotal= std::sqrt( daughtermass[1]*daughtermass[1] + mom.mag2() ); |
---|
336 | daughterparticle = |
---|
337 | new G4DynamicParticle(daughters[1], Etotal, mom); |
---|
338 | products->PushProducts(daughterparticle); |
---|
339 | |
---|
340 | if (GetVerboseLevel()>1) { |
---|
341 | G4cout << "G4GeneralPhaseSpaceDecay::ThreeBodyDecayIt "; |
---|
342 | G4cout << " create decay products in rest frame " <<G4endl; |
---|
343 | products->DumpInfo(); |
---|
344 | } |
---|
345 | return products; |
---|
346 | } |
---|
347 | |
---|
348 | G4DecayProducts *G4GeneralPhaseSpaceDecay::ManyBodyDecayIt() |
---|
349 | // algorism of this code is originally written in FORTRAN by M.Asai |
---|
350 | //***************************************************************** |
---|
351 | // NBODY |
---|
352 | // N-body phase space Monte-Carlo generator |
---|
353 | // Makoto Asai |
---|
354 | // Hiroshima Institute of Technology |
---|
355 | // (asai@kekvax.kek.jp) |
---|
356 | // Revised release : 19/Apr/1995 |
---|
357 | // |
---|
358 | { |
---|
359 | //return value |
---|
360 | G4DecayProducts *products; |
---|
361 | |
---|
362 | if (GetVerboseLevel()>1) G4cout << "G4GeneralPhaseSpaceDecay::ManyBodyDecayIt()"<<G4endl; |
---|
363 | |
---|
364 | //daughters'mass |
---|
365 | G4double *daughtermass = new G4double[numberOfDaughters]; |
---|
366 | G4double sumofdaughtermass = 0.0; |
---|
367 | for (G4int index=0; index<numberOfDaughters; index++){ |
---|
368 | daughtermass[index] = daughters[index]->GetPDGMass(); |
---|
369 | sumofdaughtermass += daughtermass[index]; |
---|
370 | } |
---|
371 | |
---|
372 | //Calculate daughter momentum |
---|
373 | G4double *daughtermomentum = new G4double[numberOfDaughters]; |
---|
374 | G4ParticleMomentum direction; |
---|
375 | G4DynamicParticle **daughterparticle; |
---|
376 | G4double *sm = new G4double[numberOfDaughters]; |
---|
377 | G4double tmas; |
---|
378 | G4double weight = 1.0; |
---|
379 | G4int numberOfTry = 0; |
---|
380 | G4int index1, index2; |
---|
381 | |
---|
382 | do { |
---|
383 | //Generate rundom number in descending order |
---|
384 | G4double temp; |
---|
385 | G4double *rd = new G4double[numberOfDaughters]; |
---|
386 | rd[0] = 1.0; |
---|
387 | for(index1 =1; index1 < numberOfDaughters -1; index1++) |
---|
388 | rd[index1] = G4UniformRand(); |
---|
389 | rd[ numberOfDaughters -1] = 0.0; |
---|
390 | for(index1 =1; index1 < numberOfDaughters -1; index1++) { |
---|
391 | for(index2 = index1+1; index2 < numberOfDaughters; index2++) { |
---|
392 | if (rd[index1] < rd[index2]){ |
---|
393 | temp = rd[index1]; |
---|
394 | rd[index1] = rd[index2]; |
---|
395 | rd[index2] = temp; |
---|
396 | } |
---|
397 | } |
---|
398 | } |
---|
399 | |
---|
400 | //calcurate virtual mass |
---|
401 | tmas = parentmass - sumofdaughtermass; |
---|
402 | temp = sumofdaughtermass; |
---|
403 | for(index1 =0; index1 < numberOfDaughters; index1++) { |
---|
404 | sm[index1] = rd[index1]*tmas + temp; |
---|
405 | temp -= daughtermass[index1]; |
---|
406 | if (GetVerboseLevel()>1) { |
---|
407 | G4cout << index1 << " rundom number:" << rd[index1]; |
---|
408 | G4cout << " virtual mass:" << sm[index1]/GeV << "[GeV/c/c]" <<G4endl; |
---|
409 | } |
---|
410 | } |
---|
411 | delete [] rd; |
---|
412 | |
---|
413 | //Calculate daughter momentum |
---|
414 | weight = 1.0; |
---|
415 | index1 =numberOfDaughters-1; |
---|
416 | daughtermomentum[index1]= Pmx( sm[index1-1],daughtermass[index1-1],sm[index1]); |
---|
417 | if (GetVerboseLevel()>1) { |
---|
418 | G4cout << " daughter " << index1 << ":" << *daughters_name[index1]; |
---|
419 | G4cout << " momentum:" << daughtermomentum[index1]/GeV << "[GeV/c]" <<G4endl; |
---|
420 | } |
---|
421 | for(index1 =numberOfDaughters-2; index1>=0; index1--) { |
---|
422 | // calculate |
---|
423 | daughtermomentum[index1]= Pmx( sm[index1],daughtermass[index1], sm[index1 +1]); |
---|
424 | if(daughtermomentum[index1] < 0.0) { |
---|
425 | // !!! illegal momentum !!! |
---|
426 | if (GetVerboseLevel()>0) { |
---|
427 | G4cout << "G4GeneralPhaseSpaceDecay::ManyBodyDecayIt "; |
---|
428 | G4cout << " can not calculate daughter momentum " <<G4endl; |
---|
429 | G4cout << " parent:" << *parent_name; |
---|
430 | G4cout << " mass:" << parentmass/GeV << "[GeV/c/c]" <<G4endl; |
---|
431 | G4cout << " daughter " << index1 << ":" << *daughters_name[index1]; |
---|
432 | G4cout << " mass:" << daughtermass[index1]/GeV << "[GeV/c/c]" ; |
---|
433 | G4cout << " mass:" << daughtermomentum[index1]/GeV << "[GeV/c]" <<G4endl; |
---|
434 | } |
---|
435 | delete [] sm; |
---|
436 | delete [] daughtermass; |
---|
437 | delete [] daughtermomentum; |
---|
438 | return NULL; // Error detection |
---|
439 | |
---|
440 | } else { |
---|
441 | // calculate weight of this events |
---|
442 | weight *= daughtermomentum[index1]/sm[index1]; |
---|
443 | if (GetVerboseLevel()>1) { |
---|
444 | G4cout << " daughter " << index1 << ":" << *daughters_name[index1]; |
---|
445 | G4cout << " momentum:" << daughtermomentum[index1]/GeV << "[GeV/c]" <<G4endl; |
---|
446 | } |
---|
447 | } |
---|
448 | } |
---|
449 | if (GetVerboseLevel()>1) { |
---|
450 | G4cout << " weight: " << weight <<G4endl; |
---|
451 | } |
---|
452 | |
---|
453 | // exit if number of Try exceeds 100 |
---|
454 | if (numberOfTry++ >100) { |
---|
455 | if (GetVerboseLevel()>0) { |
---|
456 | G4cout << "G4GeneralPhaseSpaceDecay::ManyBodyDecayIt: "; |
---|
457 | G4cout << " can not determine Decay Kinematics " << G4endl; |
---|
458 | } |
---|
459 | delete [] sm; |
---|
460 | delete [] daughtermass; |
---|
461 | delete [] daughtermomentum; |
---|
462 | return NULL; // Error detection |
---|
463 | } |
---|
464 | } while ( weight > G4UniformRand()); |
---|
465 | if (GetVerboseLevel()>1) { |
---|
466 | G4cout << "Start calulation of daughters momentum vector "<<G4endl; |
---|
467 | } |
---|
468 | |
---|
469 | G4double costheta, sintheta, phi; |
---|
470 | G4double beta; |
---|
471 | daughterparticle = new G4DynamicParticle*[numberOfDaughters]; |
---|
472 | |
---|
473 | index1 = numberOfDaughters -2; |
---|
474 | costheta = 2.*G4UniformRand()-1.0; |
---|
475 | sintheta = std::sqrt((1.0-costheta)*(1.0+costheta)); |
---|
476 | phi = twopi*G4UniformRand()*rad; |
---|
477 | direction.setZ(costheta); |
---|
478 | direction.setY(sintheta*std::sin(phi)); |
---|
479 | direction.setX(sintheta*std::cos(phi)); |
---|
480 | daughterparticle[index1] = new G4DynamicParticle( daughters[index1], direction*daughtermomentum[index1] ); |
---|
481 | daughterparticle[index1+1] = new G4DynamicParticle( daughters[index1+1], direction*(-1.0*daughtermomentum[index1]) ); |
---|
482 | |
---|
483 | for (index1 = numberOfDaughters -3; index1 >= 0; index1--) { |
---|
484 | //calculate momentum direction |
---|
485 | costheta = 2.*G4UniformRand()-1.0; |
---|
486 | sintheta = std::sqrt((1.0-costheta)*(1.0+costheta)); |
---|
487 | phi = twopi*G4UniformRand()*rad; |
---|
488 | direction.setZ(costheta); |
---|
489 | direction.setY(sintheta*std::sin(phi)); |
---|
490 | direction.setX(sintheta*std::cos(phi)); |
---|
491 | |
---|
492 | // boost already created particles |
---|
493 | beta = daughtermomentum[index1]; |
---|
494 | beta /= std::sqrt( daughtermomentum[index1]*daughtermomentum[index1] + sm[index1+1]*sm[index1+1] ); |
---|
495 | for (G4int index2 = index1+1; index2<numberOfDaughters; index2++) { |
---|
496 | G4LorentzVector p4; |
---|
497 | // make G4LorentzVector for secondaries |
---|
498 | p4 = daughterparticle[index2]->Get4Momentum(); |
---|
499 | |
---|
500 | // boost secondaries to new frame |
---|
501 | p4.boost( direction.x()*beta, direction.y()*beta, direction.z()*beta); |
---|
502 | |
---|
503 | // change energy/momentum |
---|
504 | daughterparticle[index2]->Set4Momentum(p4); |
---|
505 | } |
---|
506 | //create daughter G4DynamicParticle |
---|
507 | daughterparticle[index1]= new G4DynamicParticle( daughters[index1], direction*(-1.0*daughtermomentum[index1])); |
---|
508 | } |
---|
509 | |
---|
510 | //create G4Decayproducts |
---|
511 | G4DynamicParticle *parentparticle; |
---|
512 | direction.setX(1.0); direction.setY(0.0); direction.setZ(0.0); |
---|
513 | parentparticle = new G4DynamicParticle( parent, direction, 0.0); |
---|
514 | products = new G4DecayProducts(*parentparticle); |
---|
515 | delete parentparticle; |
---|
516 | for (index1 = 0; index1<numberOfDaughters; index1++) { |
---|
517 | products->PushProducts(daughterparticle[index1]); |
---|
518 | } |
---|
519 | if (GetVerboseLevel()>1) { |
---|
520 | G4cout << "G4GeneralPhaseSpaceDecay::ManyBodyDecayIt "; |
---|
521 | G4cout << " create decay products in rest frame " << G4endl; |
---|
522 | products->DumpInfo(); |
---|
523 | } |
---|
524 | |
---|
525 | delete [] daughterparticle; |
---|
526 | delete [] daughtermomentum; |
---|
527 | delete [] daughtermass; |
---|
528 | delete [] sm; |
---|
529 | |
---|
530 | return products; |
---|
531 | } |
---|
532 | |
---|
533 | |
---|
534 | |
---|
535 | |
---|
536 | |
---|