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8d2cd130 1/**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
3 * *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
6 * *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
15
7cdba479 16/* $Id$ */
8d2cd130 17
18#include "AliPythia.h"
7cdba479 19#include "AliPythiaRndm.h"
0f482ae4 20#include "../FASTSIM/AliFastGlauber.h"
21#include "../FASTSIM/AliQuenchingWeights.h"
22#include "TVector3.h"
8d2cd130 23
24ClassImp(AliPythia)
25
26#ifndef WIN32
27# define pyclus pyclus_
28# define pycell pycell_
452af8c7 29# define pyshow pyshow_
30# define pyrobo pyrobo_
8d2cd130 31# define type_of_call
32#else
33# define pyclus PYCLUS
34# define pycell PYCELL
452af8c7 35# define pyrobo PYROBO
8d2cd130 36# define type_of_call _stdcall
37#endif
38
39extern "C" void type_of_call pyclus(Int_t & );
40extern "C" void type_of_call pycell(Int_t & );
452af8c7 41extern "C" void type_of_call pyshow(Int_t &, Int_t &, Double_t &);
42extern "C" void type_of_call pyrobo(Int_t &, Int_t &, Double_t &, Double_t &, Double_t &, Double_t &, Double_t &);
8d2cd130 43
44//_____________________________________________________________________________
45
46AliPythia* AliPythia::fgAliPythia=NULL;
47
48AliPythia::AliPythia()
49{
50// Default Constructor
51//
52// Set random number
7cdba479 53 if (!AliPythiaRndm::GetPythiaRandom())
54 AliPythiaRndm::SetPythiaRandom(GetRandom());
0f482ae4 55 fGlauber = 0;
56 fQuenchingWeights = 0;
8d2cd130 57}
58
59void AliPythia::ProcInit(Process_t process, Float_t energy, StrucFunc_t strucfunc)
60{
61// Initialise the process to generate
7cdba479 62 if (!AliPythiaRndm::GetPythiaRandom())
63 AliPythiaRndm::SetPythiaRandom(GetRandom());
8d2cd130 64
65 fProcess = process;
66 fEcms = energy;
67 fStrucFunc = strucfunc;
68// don't decay p0
69 SetMDCY(Pycomp(111),1,0);
70// select structure function
71 SetMSTP(52,2);
72 SetMSTP(51,strucfunc);
73//
74// Pythia initialisation for selected processes//
75//
76// Make MSEL clean
77//
78 for (Int_t i=1; i<= 200; i++) {
79 SetMSUB(i,0);
80 }
81// select charm production
82 switch (process)
83 {
84 case kPyCharm:
85 SetMSEL(4);
86//
87// heavy quark masses
88
89 SetPMAS(4,1,1.2);
90 SetMSTU(16,2);
91//
92// primordial pT
93 SetMSTP(91,1);
94 SetPARP(91,1.);
95 SetPARP(93,5.);
96//
97 break;
98 case kPyBeauty:
99 SetMSEL(5);
100 SetPMAS(5,1,4.75);
101 SetMSTU(16,2);
102 break;
103 case kPyJpsi:
104 SetMSEL(0);
105// gg->J/Psi g
106 SetMSUB(86,1);
107 break;
108 case kPyJpsiChi:
109 SetMSEL(0);
110// gg->J/Psi g
111 SetMSUB(86,1);
112// gg-> chi_0c g
113 SetMSUB(87,1);
114// gg-> chi_1c g
115 SetMSUB(88,1);
116// gg-> chi_2c g
117 SetMSUB(89,1);
118 break;
119 case kPyCharmUnforced:
120 SetMSEL(0);
121// gq->qg
122 SetMSUB(28,1);
123// gg->qq
124 SetMSUB(53,1);
125// gg->gg
126 SetMSUB(68,1);
127 break;
128 case kPyBeautyUnforced:
129 SetMSEL(0);
130// gq->qg
131 SetMSUB(28,1);
132// gg->qq
133 SetMSUB(53,1);
134// gg->gg
135 SetMSUB(68,1);
136 break;
137 case kPyMb:
138// Minimum Bias pp-Collisions
139//
140//
141// select Pythia min. bias model
142 SetMSEL(0);
511db649 143 SetMSUB(92,1); // single diffraction AB-->XB
144 SetMSUB(93,1); // single diffraction AB-->AX
145 SetMSUB(94,1); // double diffraction
146 SetMSUB(95,1); // low pt production
147
148//
149// ATLAS Tuning
150//
c01c4118 151
152 SetMSTP(51, kCTEQ5L); // CTEQ5L pdf
511db649 153 SetMSTP(81,1); // Multiple Interactions ON
154 SetMSTP(82,4); // Double Gaussian Model
155
156 SetPARP(82,1.8); // [GeV] PT_min at Ref. energy
157 SetPARP(89,1000.); // [GeV] Ref. energy
158 SetPARP(90,0.16); // 2*epsilon (exponent in power law)
159 SetPARP(83,0.5); // Core density in proton matter distribution (def.value)
160 SetPARP(84,0.5); // Core radius
161 SetPARP(85,0.33); // Regulates gluon prod. mechanism
162 SetPARP(86,0.66); // Regulates gluon prod. mechanism
163 SetPARP(67,1); // Regulates Initial State Radiation
164 break;
8d2cd130 165 case kPyMbNonDiffr:
166// Minimum Bias pp-Collisions
167//
168//
169// select Pythia min. bias model
170 SetMSEL(0);
511db649 171 SetMSUB(95,1); // low pt production
0f482ae4 172
173//
174// ATLAS Tuning
175//
511db649 176
0f482ae4 177 SetMSTP(51,7); // CTEQ5L pdf
511db649 178 SetMSTP(81,1); // Multiple Interactions ON
179 SetMSTP(82,4); // Double Gaussian Model
180
181 SetPARP(82,1.8); // [GeV] PT_min at Ref. energy
182 SetPARP(89,1000.); // [GeV] Ref. energy
183 SetPARP(90,0.16); // 2*epsilon (exponent in power law)
184 SetPARP(83,0.5); // Core density in proton matter distribution (def.value)
185 SetPARP(84,0.5); // Core radius
186 SetPARP(85,0.33); // Regulates gluon prod. mechanism
187 SetPARP(86,0.66); // Regulates gluon prod. mechanism
188 SetPARP(67,1); // Regulates Initial State Radiation
8d2cd130 189 break;
190 case kPyJets:
191//
192// QCD Jets
193//
194 SetMSEL(1);
195 break;
196 case kPyDirectGamma:
197 SetMSEL(10);
198 break;
adf4d898 199 case kPyCharmPbPbMNR:
200 case kPyD0PbPbMNR:
8d2cd130 201 // Tuning of Pythia parameters aimed to get a resonable agreement
202 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
203 // c-cbar single inclusive and double differential distributions.
204 // This parameter settings are meant to work with Pb-Pb collisions
adf4d898 205 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
8d2cd130 206 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
207 // has to be set to 2.1GeV. Example in ConfigCharmPPR.C.
208
209 // All QCD processes
210 SetMSEL(1);
211
212 // No multiple interactions
213 SetMSTP(81,0);
214 SetPARP(81,0.0);
215 SetPARP(82,0.0);
216
217 // Initial/final parton shower on (Pythia default)
218 SetMSTP(61,1);
219 SetMSTP(71,1);
220
221 // 2nd order alpha_s
222 SetMSTP(2,2);
223
224 // QCD scales
225 SetMSTP(32,2);
226 SetPARP(34,1.0);
227
adf4d898 228 // Intrinsic <kT>
8d2cd130 229 SetMSTP(91,1);
230 SetPARP(91,1.304);
231 SetPARP(93,6.52);
232
233 // Set c-quark mass
234 SetPMAS(4,1,1.2);
235
90d7b703 236 break;
237 case kPyDPlusPbPbMNR:
238 // Tuning of Pythia parameters aimed to get a resonable agreement
239 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
240 // c-cbar single inclusive and double differential distributions.
241 // This parameter settings are meant to work with Pb-Pb collisions
242 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
243 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
244 // has to be set to 2.1GeV. Example in ConfigCharmPPR.C.
245
246 // All QCD processes
247 SetMSEL(1);
248
249 // No multiple interactions
250 SetMSTP(81,0);
251 SetPARP(81,0.0);
252 SetPARP(82,0.0);
253
254 // Initial/final parton shower on (Pythia default)
255 SetMSTP(61,1);
256 SetMSTP(71,1);
257
258 // 2nd order alpha_s
259 SetMSTP(2,2);
260
261 // QCD scales
262 SetMSTP(32,2);
263 SetPARP(34,1.0);
264
265 // Intrinsic <kT>
266 SetMSTP(91,1);
267 SetPARP(91,1.304);
268 SetPARP(93,6.52);
269
270 // Set c-quark mass
271 SetPMAS(4,1,1.2);
272
8d2cd130 273 break;
adf4d898 274 case kPyCharmpPbMNR:
275 case kPyD0pPbMNR:
276 // Tuning of Pythia parameters aimed to get a resonable agreement
277 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
278 // c-cbar single inclusive and double differential distributions.
279 // This parameter settings are meant to work with p-Pb collisions
280 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
281 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
282 // has to be set to 2.1GeV. Example in ConfigCharmPPR.C.
283
284 // All QCD processes
285 SetMSEL(1);
286
287 // No multiple interactions
288 SetMSTP(81,0);
289 SetPARP(81,0.0);
290 SetPARP(82,0.0);
291
292 // Initial/final parton shower on (Pythia default)
293 SetMSTP(61,1);
294 SetMSTP(71,1);
295
296 // 2nd order alpha_s
297 SetMSTP(2,2);
298
299 // QCD scales
300 SetMSTP(32,2);
301 SetPARP(34,1.0);
302
303 // Intrinsic <kT>
304 SetMSTP(91,1);
305 SetPARP(91,1.16);
306 SetPARP(93,5.8);
307
308 // Set c-quark mass
309 SetPMAS(4,1,1.2);
310
90d7b703 311 break;
312 case kPyDPluspPbMNR:
313 // Tuning of Pythia parameters aimed to get a resonable agreement
314 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
315 // c-cbar single inclusive and double differential distributions.
316 // This parameter settings are meant to work with p-Pb collisions
317 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
318 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
319 // has to be set to 2.1GeV. Example in ConfigCharmPPR.C.
320
321 // All QCD processes
322 SetMSEL(1);
323
324 // No multiple interactions
325 SetMSTP(81,0);
326 SetPARP(81,0.0);
327 SetPARP(82,0.0);
328
329 // Initial/final parton shower on (Pythia default)
330 SetMSTP(61,1);
331 SetMSTP(71,1);
332
333 // 2nd order alpha_s
334 SetMSTP(2,2);
335
336 // QCD scales
337 SetMSTP(32,2);
338 SetPARP(34,1.0);
339
340 // Intrinsic <kT>
341 SetMSTP(91,1);
342 SetPARP(91,1.16);
343 SetPARP(93,5.8);
344
345 // Set c-quark mass
346 SetPMAS(4,1,1.2);
347
adf4d898 348 break;
349 case kPyCharmppMNR:
350 case kPyD0ppMNR:
351 // Tuning of Pythia parameters aimed to get a resonable agreement
352 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
353 // c-cbar single inclusive and double differential distributions.
354 // This parameter settings are meant to work with pp collisions
355 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
356 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
357 // has to be set to 2.1GeV. Example in ConfigCharmPPR.C.
358
359 // All QCD processes
360 SetMSEL(1);
361
362 // No multiple interactions
363 SetMSTP(81,0);
364 SetPARP(81,0.0);
365 SetPARP(82,0.0);
366
367 // Initial/final parton shower on (Pythia default)
368 SetMSTP(61,1);
369 SetMSTP(71,1);
370
371 // 2nd order alpha_s
372 SetMSTP(2,2);
373
374 // QCD scales
375 SetMSTP(32,2);
376 SetPARP(34,1.0);
377
378 // Intrinsic <kT^2>
379 SetMSTP(91,1);
380 SetPARP(91,1.);
381 SetPARP(93,5.);
382
383 // Set c-quark mass
384 SetPMAS(4,1,1.2);
385
90d7b703 386 break;
387 case kPyDPlusppMNR:
388 // Tuning of Pythia parameters aimed to get a resonable agreement
389 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
390 // c-cbar single inclusive and double differential distributions.
391 // This parameter settings are meant to work with pp collisions
392 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
393 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
394 // has to be set to 2.1GeV. Example in ConfigCharmPPR.C.
395
396 // All QCD processes
397 SetMSEL(1);
398
399 // No multiple interactions
400 SetMSTP(81,0);
401 SetPARP(81,0.0);
402 SetPARP(82,0.0);
403
404 // Initial/final parton shower on (Pythia default)
405 SetMSTP(61,1);
406 SetMSTP(71,1);
407
408 // 2nd order alpha_s
409 SetMSTP(2,2);
410
411 // QCD scales
412 SetMSTP(32,2);
413 SetPARP(34,1.0);
414
415 // Intrinsic <kT^2>
416 SetMSTP(91,1);
417 SetPARP(91,1.);
418 SetPARP(93,5.);
419
420 // Set c-quark mass
421 SetPMAS(4,1,1.2);
422
adf4d898 423 break;
424 case kPyBeautyPbPbMNR:
8d2cd130 425 // Tuning of Pythia parameters aimed to get a resonable agreement
426 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
427 // b-bbar single inclusive and double differential distributions.
428 // This parameter settings are meant to work with Pb-Pb collisions
429 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
430 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
431 // has to be set to 2.75GeV. Example in ConfigBeautyPPR.C.
432
433 // All QCD processes
434 SetMSEL(1);
435
436 // No multiple interactions
437 SetMSTP(81,0);
438 SetPARP(81,0.0);
439 SetPARP(82,0.0);
440
441 // Initial/final parton shower on (Pythia default)
442 SetMSTP(61,1);
443 SetMSTP(71,1);
444
445 // 2nd order alpha_s
446 SetMSTP(2,2);
447
448 // QCD scales
449 SetMSTP(32,2);
450 SetPARP(34,1.0);
451 SetPARP(67,1.0);
452 SetPARP(71,1.0);
453
adf4d898 454 // Intrinsic <kT>
8d2cd130 455 SetMSTP(91,1);
456 SetPARP(91,2.035);
457 SetPARP(93,10.17);
458
459 // Set b-quark mass
460 SetPMAS(5,1,4.75);
461
adf4d898 462 break;
463 case kPyBeautypPbMNR:
464 // Tuning of Pythia parameters aimed to get a resonable agreement
465 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
466 // b-bbar single inclusive and double differential distributions.
467 // This parameter settings are meant to work with p-Pb collisions
468 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
469 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
470 // has to be set to 2.75GeV. Example in ConfigBeautyPPR.C.
471
472 // All QCD processes
473 SetMSEL(1);
474
475 // No multiple interactions
476 SetMSTP(81,0);
477 SetPARP(81,0.0);
478 SetPARP(82,0.0);
479
480 // Initial/final parton shower on (Pythia default)
481 SetMSTP(61,1);
482 SetMSTP(71,1);
483
484 // 2nd order alpha_s
485 SetMSTP(2,2);
486
487 // QCD scales
488 SetMSTP(32,2);
489 SetPARP(34,1.0);
490 SetPARP(67,1.0);
491 SetPARP(71,1.0);
492
493 // Intrinsic <kT>
494 SetMSTP(91,1);
495 SetPARP(91,1.60);
496 SetPARP(93,8.00);
497
498 // Set b-quark mass
499 SetPMAS(5,1,4.75);
500
501 break;
502 case kPyBeautyppMNR:
503 // Tuning of Pythia parameters aimed to get a resonable agreement
504 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
505 // b-bbar single inclusive and double differential distributions.
506 // This parameter settings are meant to work with pp collisions
507 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
508 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
509 // has to be set to 2.75GeV. Example in ConfigBeautyPPR.C.
510
511 // All QCD processes
512 SetMSEL(1);
513
514 // No multiple interactions
515 SetMSTP(81,0);
516 SetPARP(81,0.0);
517 SetPARP(82,0.0);
518
519 // Initial/final parton shower on (Pythia default)
520 SetMSTP(61,1);
521 SetMSTP(71,1);
522
523 // 2nd order alpha_s
524 SetMSTP(2,2);
525
526 // QCD scales
527 SetMSTP(32,2);
528 SetPARP(34,1.0);
529 SetPARP(67,1.0);
530 SetPARP(71,1.0);
531
532 // Intrinsic <kT>
533 SetMSTP(91,1);
534 SetPARP(91,1.);
535 SetPARP(93,5.);
536
537 // Set b-quark mass
538 SetPMAS(5,1,4.75);
539
8d2cd130 540 break;
541 }
542//
543// Initialize PYTHIA
544 SetMSTP(41,1); // all resonance decays switched on
545
546 Initialize("CMS","p","p",fEcms);
547
548}
549
550Int_t AliPythia::CheckedLuComp(Int_t kf)
551{
552// Check Lund particle code (for debugging)
553 Int_t kc=Pycomp(kf);
554 printf("\n Lucomp kf,kc %d %d",kf,kc);
555 return kc;
556}
557
558void AliPythia::SetNuclei(Int_t a1, Int_t a2)
559{
560// Treat protons as inside nuclei with mass numbers a1 and a2
561// The MSTP array in the PYPARS common block is used to enable and
562// select the nuclear structure functions.
563// MSTP(52) : (D=1) choice of proton and nuclear structure-function library
564// =1: internal PYTHIA acording to MSTP(51)
565// =2: PDFLIB proton s.f., with MSTP(51) = 1000xNGROUP+NSET
566// If the following mass number both not equal zero, nuclear corrections of the stf are used.
567// MSTP(192) : Mass number of nucleus side 1
568// MSTP(193) : Mass number of nucleus side 2
569 SetMSTP(52,2);
570 SetMSTP(192, a1);
571 SetMSTP(193, a2);
572}
573
574
575AliPythia* AliPythia::Instance()
576{
577// Set random number generator
578 if (fgAliPythia) {
579 return fgAliPythia;
580 } else {
581 fgAliPythia = new AliPythia();
582 return fgAliPythia;
583 }
584}
585
586void AliPythia::PrintParticles()
587{
588// Print list of particl properties
589 Int_t np = 0;
c31f1d37 590 char* name = new char[16];
8d2cd130 591 for (Int_t kf=0; kf<1000000; kf++) {
592 for (Int_t c = 1; c > -2; c-=2) {
8d2cd130 593 Int_t kc = Pycomp(c*kf);
594 if (kc) {
595 Float_t mass = GetPMAS(kc,1);
596 Float_t width = GetPMAS(kc,2);
597 Float_t tau = GetPMAS(kc,4);
c31f1d37 598
8d2cd130 599 Pyname(kf,name);
600
601 np++;
602
603 printf("\n mass, width, tau: %6d %s %10.3f %10.3e %10.3e",
604 c*kf, name, mass, width, tau);
605 }
606 }
607 }
608 printf("\n Number of particles %d \n \n", np);
609}
610
611void AliPythia::ResetDecayTable()
612{
613// Set default values for pythia decay switches
614 Int_t i;
615 for (i = 1; i < 501; i++) SetMDCY(i,1,fDefMDCY[i]);
616 for (i = 1; i < 2001; i++) SetMDME(i,1,fDefMDME[i]);
617}
618
619void AliPythia::SetDecayTable()
620{
621// Set default values for pythia decay switches
622//
623 Int_t i;
624 for (i = 1; i < 501; i++) fDefMDCY[i] = GetMDCY(i,1);
625 for (i = 1; i < 2001; i++) fDefMDME[i] = GetMDME(i,1);
626}
627
628void AliPythia::Pyclus(Int_t& njet)
629{
630// Call Pythia clustering algorithm
631//
632 pyclus(njet);
633}
634
635void AliPythia::Pycell(Int_t& njet)
636{
637// Call Pythia jet reconstruction algorithm
638//
639 pycell(njet);
640}
641
452af8c7 642void AliPythia::Pyshow(Int_t ip1, Int_t ip2, Double_t qmax)
643{
644// Call Pythia jet reconstruction algorithm
645//
452af8c7 646 pyshow(ip1, ip2, qmax);
647}
648
649void AliPythia::Pyrobo(Int_t imi, Int_t ima, Double_t the, Double_t phi, Double_t bex, Double_t bey, Double_t bez)
650{
651 pyrobo(imi, ima, the, phi, bex, bey, bez);
652}
653
654
655
86b6ad68 656void AliPythia::InitQuenching(Float_t cMin, Float_t cMax, Float_t k, Int_t iECMethod)
0f482ae4 657{
658// Initializes
659// (1) The quenching model using quenching weights according to C. Salgado and U. Wiedemann
660// (2) The nuclear geometry using the Glauber Model
661//
662
663
664 fGlauber = new AliFastGlauber();
665 fGlauber->Init(2);
666 fGlauber->SetCentralityClass(cMin, cMax);
667
668 fQuenchingWeights = new AliQuenchingWeights();
669 fQuenchingWeights->InitMult();
86b6ad68 670 fQuenchingWeights->SetK(k);
0f482ae4 671 fQuenchingWeights->SetECMethod(AliQuenchingWeights::kECMethod(iECMethod));
0f482ae4 672}
673
674
452af8c7 675void AliPythia::Quench()
676{
677//
678//
679// Simple Jet Quenching routine:
680// =============================
681// The jet formed by all final state partons radiated by the parton created
0f482ae4 682// in the hard collisions is quenched by a factor (1-z) using light cone variables in
683// the initial parton reference frame:
452af8c7 684// (E + p_z)new = (1-z) (E + p_z)old
685//
0f482ae4 686//
687//
688//
452af8c7 689// The lost momentum is first balanced by one gluon with virtuality > 0.
690// Subsequently the gluon splits to yield two gluons with E = p.
691//
0f482ae4 692//
693//
4e383037 694 static Float_t eMean = 0.;
695 static Int_t icall = 0;
0f482ae4 696
c2c598a3 697 Double_t p0[4][5];
698 Double_t p1[4][5];
699 Double_t p2[4][5];
700 Int_t klast[4] = {-1, -1, -1, -1};
452af8c7 701
702 Int_t numpart = fPyjets->N;
86b6ad68 703 Double_t px = 0., py = 0., pz = 0., e = 0., m = 0., p = 0., pt = 0., theta = 0., phi = 0.;
c2c598a3 704 Double_t pxq[4], pyq[4], pzq[4], eq[4], yq[4], mq[4], pq[4], phiq[4], thetaq[4], ptq[4];
705 Bool_t quenched[4];
c2c598a3 706 Double_t zInitial[4], wjtKick[4];
707 Int_t nGluon[4];
86b6ad68 708 Int_t qPdg[4];
0f482ae4 709 Int_t imo, kst, pdg;
511db649 710//
c2c598a3 711// Sore information about Primary partons
712//
713// j =
714// 0, 1 partons from hard scattering
715// 2, 3 partons from initial state radiation
716//
717 for (Int_t i = 2; i <= 7; i++) {
718 Int_t j = 0;
719 // Skip gluons that participate in hard scattering
720 if (i == 4 || i == 5) continue;
721 // Gluons from hard Scattering
722 if (i == 6 || i == 7) {
723 j = i - 6;
724 pxq[j] = fPyjets->P[0][i];
725 pyq[j] = fPyjets->P[1][i];
726 pzq[j] = fPyjets->P[2][i];
727 eq[j] = fPyjets->P[3][i];
728 mq[j] = fPyjets->P[4][i];
729 } else {
730 // Gluons from initial state radiation
731 //
732 // Obtain 4-momentum vector from difference between original parton and parton after gluon
733 // radiation. Energy is calculated independently because initial state radition does not
734 // conserve strictly momentum and energy for each partonic system independently.
735 //
736 // Not very clean. Should be improved !
737 //
738 //
739 j = i;
740 pxq[j] = fPyjets->P[0][i] - fPyjets->P[0][i+2];
741 pyq[j] = fPyjets->P[1][i] - fPyjets->P[1][i+2];
742 pzq[j] = fPyjets->P[2][i] - fPyjets->P[2][i+2];
743 mq[j] = fPyjets->P[4][i];
744 eq[j] = TMath::Sqrt(pxq[j] * pxq[j] + pyq[j] * pyq[j] + pzq[j] * pzq[j] + mq[j] * mq[j]);
745 }
746//
747// Calculate some kinematic variables
511db649 748//
4e383037 749 yq[j] = 0.5 * TMath::Log((eq[j] + pzq[j] + 1.e-14) / (eq[j] - pzq[j] + 1.e-14));
0f482ae4 750 pq[j] = TMath::Sqrt(pxq[j] * pxq[j] + pyq[j] * pyq[j] + pzq[j] * pzq[j]);
751 phiq[j] = TMath::Pi()+TMath::ATan2(-pyq[j], -pxq[j]);
752 ptq[j] = TMath::Sqrt(pxq[j] * pxq[j] + pyq[j] * pyq[j]);
753 thetaq[j] = TMath::ATan2(ptq[j], pzq[j]);
86b6ad68 754 qPdg[j] = fPyjets->K[1][i];
755 }
756
757 Double_t int0[4];
758 Double_t int1[4];
759
760 fGlauber->GetI0I1ForPythia(4, phiq, int0, int1, 15.);
761
762 for (Int_t j = 0; j < 4; j++) {
c2c598a3 763 //
764 // Quench only central jets and with E > 10.
765 //
86b6ad68 766
767
768 Int_t itype = (qPdg[j] == 21) ? 2 : 1;
769 Double_t eloss = fQuenchingWeights->GetELossRandomKFast(itype, int0[j], int1[j], eq[j]);
770
c2c598a3 771 if (TMath::Abs(yq[j]) > 2.5 || eq[j] < 10.) {
0f482ae4 772 zInitial[j] = 0.;
773 } else {
c2c598a3 774 if (eq[j] > 40. && TMath::Abs(yq[j]) < 0.5) {
4e383037 775 icall ++;
776 eMean += eloss;
777 }
0f482ae4 778 //
779 // Extra pt
86b6ad68 780 Double_t l = fQuenchingWeights->CalcLk(int0[j], int1[j]);
781 wjtKick[j] = TMath::Sqrt(l * fQuenchingWeights->CalcQk(int0[j], int1[j]));
0f482ae4 782 //
783 // Fractional energy loss
784 zInitial[j] = eloss / eq[j];
785 //
786 // Avoid complete loss
787 //
788 if (zInitial[j] == 1.) zInitial[j] = 0.95;
789 //
790 // Some debug printing
86b6ad68 791
792
bf9bb016 793// printf("Initial parton # %3d, Type %3d Energy %10.3f Phi %10.3f Length %10.3f Loss %10.3f Kick %10.3f Mean: %10.3f %10.3f\n",
794// j, itype, eq[j], phiq[j], l, eloss, wjtKick[j], eMean / Float_t(icall+1), yq[j]);
4e383037 795
c2c598a3 796// zInitial[j] = 0.8;
797// while (zInitial[j] >= 0.95) zInitial[j] = gRandom->Exp(0.2);
0f482ae4 798 }
4e383037 799
0f482ae4 800 quenched[j] = (zInitial[j] > 0.01);
4e383037 801 } // primary partons
c2c598a3 802
6e90ad26 803 Double_t pNew[1000][4];
804 Int_t kNew[1000];
805 Int_t icount = 0;
806//
4e383037 807// System Loop
c2c598a3 808 for (Int_t isys = 0; isys < 4; isys++) {
6e90ad26 809// Skip to next system if not quenched.
4e383037 810 if (!quenched[isys]) continue;
811
812 nGluon[isys] = 1 + Int_t(zInitial[isys] / (1. - zInitial[isys]));
813 if (nGluon[isys] > 6) nGluon[isys] = 6;
814 zInitial[isys] = 1. - TMath::Power(1. - zInitial[isys], 1./Double_t(nGluon[isys]));
815 wjtKick[isys] = wjtKick[isys] / TMath::Sqrt(Double_t(nGluon[isys]));
0f482ae4 816
4e383037 817
818
819 Int_t igMin = -1;
820 Int_t igMax = -1;
821 Double_t pg[4] = {0., 0., 0., 0.};
822
823//
824// Loop on radiation events
825
826 for (Int_t iglu = 0; iglu < nGluon[isys]; iglu++) {
6e90ad26 827 while (1) {
828 icount = 0;
829 for (Int_t k = 0; k < 4; k++)
830 {
831 p0[isys][k] = 0.;
832 p1[isys][k] = 0.;
833 p2[isys][k] = 0.;
834 }
835// Loop over partons
836 for (Int_t i = 0; i < numpart; i++)
837 {
838 imo = fPyjets->K[2][i];
839 kst = fPyjets->K[0][i];
840 pdg = fPyjets->K[1][i];
841
842
843
0f482ae4 844// Quarks and gluons only
6e90ad26 845 if (pdg != 21 && TMath::Abs(pdg) > 6) continue;
0f482ae4 846// Particles from hard scattering only
c2c598a3 847
6e90ad26 848 if (imo > 8 && imo < 1000) imo = fPyjets->K[2][imo - 1];
c2c598a3 849 Int_t imom = imo % 1000;
850 if ((isys == 0 || isys == 1) && ((imom != (isys + 7)))) continue;
851 if ((isys == 2 || isys == 3) && ((imom != (isys + 1)))) continue;
852
6e90ad26 853
0f482ae4 854// Skip comment lines
6e90ad26 855 if (kst != 1 && kst != 2) continue;
0f482ae4 856//
857// Parton kinematic
6e90ad26 858 px = fPyjets->P[0][i];
859 py = fPyjets->P[1][i];
860 pz = fPyjets->P[2][i];
861 e = fPyjets->P[3][i];
862 m = fPyjets->P[4][i];
863 pt = TMath::Sqrt(px * px + py * py);
864 p = TMath::Sqrt(px * px + py * py + pz * pz);
865 phi = TMath::Pi() + TMath::ATan2(-py, -px);
866 theta = TMath::ATan2(pt, pz);
867
0f482ae4 868//
c2c598a3 869// Save 4-momentum sum for balancing
870 Int_t index = isys;
6e90ad26 871
872 p0[index][0] += px;
873 p0[index][1] += py;
874 p0[index][2] += pz;
875 p0[index][3] += e;
6e90ad26 876
877 klast[index] = i;
878
0f482ae4 879//
880// Fractional energy loss
6e90ad26 881 Double_t z = zInitial[index];
4e383037 882
c2c598a3 883
4e383037 884// Don't fully quench radiated gluons
885//
886 if (imo > 1000) {
887// This small factor makes sure that the gluons are not too close in phase space to avoid recombination
888//
889
c2c598a3 890 z = 0.02;
4e383037 891 }
c2c598a3 892// printf("z: %d %f\n", imo, z);
893
4e383037 894
895//
6e90ad26 896
897 //
898 //
899 // Transform into frame in which initial parton is along z-axis
900 //
901 TVector3 v(px, py, pz);
902 v.RotateZ(-phiq[index]); v.RotateY(-thetaq[index]);
903 Double_t pxs = v.X(); Double_t pys = v.Y(); Double_t pl = v.Z();
904
905 Double_t jt = TMath::Sqrt(pxs * pxs + pys * pys);
906 Double_t mt2 = jt * jt + m * m;
907 Double_t zmax = 1.;
908 //
909 // Kinematic limit on z
910 //
4e383037 911 if (m > 0.) zmax = 1. - m / TMath::Sqrt(m * m + jt * jt);
6e90ad26 912 //
913 // Change light-cone kinematics rel. to initial parton
914 //
915 Double_t eppzOld = e + pl;
916 Double_t empzOld = e - pl;
917
918 Double_t eppzNew = (1. - z) * eppzOld;
919 Double_t empzNew = empzOld - mt2 * z / eppzOld;
920 Double_t eNew = 0.5 * (eppzNew + empzNew);
921 Double_t plNew = 0.5 * (eppzNew - empzNew);
922
923 Double_t jtNew;
924 //
925 // if mt very small (or sometimes even < 0 for numerical reasons) set it to 0
926 Double_t mt2New = eppzNew * empzNew;
927 if (mt2New < 1.e-8) mt2New = 0.;
4e383037 928 if (z < zmax) {
929 if (m * m > mt2New) {
930 //
931 // This should not happen
932 //
933 Fatal("Quench()", "This should never happen %e %e %e!", m, eppzNew, empzNew);
934 jtNew = 0;
935 } else {
936 jtNew = TMath::Sqrt(mt2New - m * m);
937 }
6e90ad26 938 } else {
4e383037 939 // If pT is to small (probably a leading massive particle) we scale only the energy
940 // This can cause negative masses of the radiated gluon
941 // Let's hope for the best ...
942 jtNew = jt;
943 eNew = TMath::Sqrt(plNew * plNew + mt2);
944
6e90ad26 945 }
6e90ad26 946 //
947 // Calculate new px, py
948 //
949 Double_t pxNew = jtNew / jt * pxs;
950 Double_t pyNew = jtNew / jt * pys;
951
952// Double_t dpx = pxs - pxNew;
953// Double_t dpy = pys - pyNew;
954// Double_t dpz = pl - plNew;
955// Double_t de = e - eNew;
956// Double_t dmass2 = de * de - dpx * dpx - dpy * dpy - dpz * dpz;
957// printf("New mass (1) %e %e %e %e %e %e %e \n", dmass2, jt, jtNew, pl, plNew, e, eNew);
958// printf("New mass (2) %e %e \n", pxNew, pyNew);
959 //
960 // Rotate back
961 //
962 TVector3 w(pxNew, pyNew, plNew);
963 w.RotateY(thetaq[index]); w.RotateZ(phiq[index]);
964 pxNew = w.X(); pyNew = w.Y(); plNew = w.Z();
965
966 p1[index][0] += pxNew;
967 p1[index][1] += pyNew;
968 p1[index][2] += plNew;
969 p1[index][3] += eNew;
970 //
971 // Updated 4-momentum vectors
972 //
973 pNew[icount][0] = pxNew;
974 pNew[icount][1] = pyNew;
975 pNew[icount][2] = plNew;
976 pNew[icount][3] = eNew;
977 kNew[icount] = i;
978 icount++;
979 } // parton loop
0f482ae4 980 //
6e90ad26 981 // Check if there was phase-space for quenching
0f482ae4 982 //
0f482ae4 983
6e90ad26 984 if (icount == 0) quenched[isys] = kFALSE;
985 if (!quenched[isys]) break;
986
987 for (Int_t j = 0; j < 4; j++)
988 {
989 p2[isys][j] = p0[isys][j] - p1[isys][j];
990 }
991 p2[isys][4] = p2[isys][3] * p2[isys][3] - p2[isys][0] * p2[isys][0] - p2[isys][1] * p2[isys][1] - p2[isys][2] * p2[isys][2];
6e90ad26 992 if (p2[isys][4] > 0.) {
993 p2[isys][4] = TMath::Sqrt(p2[isys][4]);
994 break;
995 } else {
996 printf("Warning negative mass squared in system %d %f ! \n", isys, zInitial[isys]);
4e383037 997 printf("4-Momentum: %10.3e %10.3e %10.3e %10.3e %10.3e \n", p2[isys][0], p2[isys][1], p2[isys][2], p2[isys][3], p2[isys][4]);
6e90ad26 998 if (p2[isys][4] < -0.01) {
4e383037 999 printf("Negative mass squared !\n");
1000 // Here we have to put the gluon back to mass shell
1001 // This will lead to a small energy imbalance
1002 p2[isys][4] = 0.;
1003 p2[isys][3] = TMath::Sqrt(p2[isys][0] * p2[isys][0] + p2[isys][1] * p2[isys][1] + p2[isys][2] * p2[isys][2]);
1004 break;
6e90ad26 1005 } else {
1006 p2[isys][4] = 0.;
1007 break;
1008 }
1009 }
6e90ad26 1010 /*
6e90ad26 1011 zHeavy *= 0.98;
1012 printf("zHeavy lowered to %f\n", zHeavy);
1013 if (zHeavy < 0.01) {
1014 printf("No success ! \n");
1015 icount = 0;
1016 quenched[isys] = kFALSE;
1017 break;
1018 }
4e383037 1019 */
1020 } // iteration on z (while)
1021
6e90ad26 1022// Update event record
1023 for (Int_t k = 0; k < icount; k++) {
1024// printf("%6d %6d %10.3e %10.3e %10.3e %10.3e\n", k, kNew[k], pNew[k][0],pNew[k][1], pNew[k][2], pNew[k][3] );
1025 fPyjets->P[0][kNew[k]] = pNew[k][0];
1026 fPyjets->P[1][kNew[k]] = pNew[k][1];
1027 fPyjets->P[2][kNew[k]] = pNew[k][2];
1028 fPyjets->P[3][kNew[k]] = pNew[k][3];
0f482ae4 1029 }
4e383037 1030 //
1031 // Add the gluons
1032 //
1033 Int_t ish = 0;
1837e95c 1034 Int_t iGlu;
4e383037 1035 if (!quenched[isys]) continue;
0f482ae4 1036//
1037// Last parton from shower i
4e383037 1038 Int_t in = klast[isys];
0f482ae4 1039//
1040// Continue if no parton in shower i selected
1041 if (in == -1) continue;
1042//
1043// If this is the second initial parton and it is behind the first move pointer by previous ish
4e383037 1044 if (isys == 1 && klast[1] > klast[0]) in += ish;
0f482ae4 1045//
1046// Starting index
452af8c7 1047
4e383037 1048// jmin = in - 1;
0f482ae4 1049// How many additional gluons will be generated
1050 ish = 1;
4e383037 1051 if (p2[isys][4] > 0.05) ish = 2;
0f482ae4 1052//
1053// Position of gluons
4e383037 1054 iGlu = numpart;
1055 if (iglu == 0) igMin = iGlu;
1056 igMax = iGlu;
0f482ae4 1057 numpart += ish;
1058 (fPyjets->N) += ish;
4e383037 1059
0f482ae4 1060 if (ish == 1) {
4e383037 1061 fPyjets->P[0][iGlu] = p2[isys][0];
1062 fPyjets->P[1][iGlu] = p2[isys][1];
1063 fPyjets->P[2][iGlu] = p2[isys][2];
1064 fPyjets->P[3][iGlu] = p2[isys][3];
1065 fPyjets->P[4][iGlu] = p2[isys][4];
0f482ae4 1066
4e383037 1067 fPyjets->K[0][iGlu] = 1;
1068 if (iglu == nGluon[isys] - 1) fPyjets->K[0][iGlu] = 1;
0f482ae4 1069 fPyjets->K[1][iGlu] = 21;
4e383037 1070 fPyjets->K[2][iGlu] = fPyjets->K[2][in] + 1000;
0f482ae4 1071 fPyjets->K[3][iGlu] = -1;
1072 fPyjets->K[4][iGlu] = -1;
4e383037 1073
1074 pg[0] += p2[isys][0];
1075 pg[1] += p2[isys][1];
1076 pg[2] += p2[isys][2];
1077 pg[3] += p2[isys][3];
0f482ae4 1078 } else {
1079 //
1080 // Split gluon in rest frame.
1081 //
4e383037 1082 Double_t bx = p2[isys][0] / p2[isys][3];
1083 Double_t by = p2[isys][1] / p2[isys][3];
1084 Double_t bz = p2[isys][2] / p2[isys][3];
1085 Double_t pst = p2[isys][4] / 2.;
0f482ae4 1086 //
1087 // Isotropic decay ????
1088 Double_t cost = 2. * gRandom->Rndm() - 1.;
1089 Double_t sint = TMath::Sqrt(1. - cost * cost);
1090 Double_t phi = 2. * TMath::Pi() * gRandom->Rndm();
1091
1092 Double_t pz1 = pst * cost;
1093 Double_t pz2 = -pst * cost;
1094 Double_t pt1 = pst * sint;
1095 Double_t pt2 = -pst * sint;
1096 Double_t px1 = pt1 * TMath::Cos(phi);
1097 Double_t py1 = pt1 * TMath::Sin(phi);
1098 Double_t px2 = pt2 * TMath::Cos(phi);
1099 Double_t py2 = pt2 * TMath::Sin(phi);
1100
1101 fPyjets->P[0][iGlu] = px1;
1102 fPyjets->P[1][iGlu] = py1;
1103 fPyjets->P[2][iGlu] = pz1;
1104 fPyjets->P[3][iGlu] = pst;
1105 fPyjets->P[4][iGlu] = 0.;
1106
4e383037 1107 fPyjets->K[0][iGlu] = 1 ;
0f482ae4 1108 fPyjets->K[1][iGlu] = 21;
4e383037 1109 fPyjets->K[2][iGlu] = fPyjets->K[2][in] + 1000;
0f482ae4 1110 fPyjets->K[3][iGlu] = -1;
1111 fPyjets->K[4][iGlu] = -1;
1112
1113 fPyjets->P[0][iGlu+1] = px2;
1114 fPyjets->P[1][iGlu+1] = py2;
1115 fPyjets->P[2][iGlu+1] = pz2;
1116 fPyjets->P[3][iGlu+1] = pst;
1117 fPyjets->P[4][iGlu+1] = 0.;
1118
4e383037 1119 fPyjets->K[0][iGlu+1] = 1;
1120 if (iglu == nGluon[isys] - 1) fPyjets->K[0][iGlu+1] = 1;
0f482ae4 1121 fPyjets->K[1][iGlu+1] = 21;
4e383037 1122 fPyjets->K[2][iGlu+1] = fPyjets->K[2][in] + 1000;
0f482ae4 1123 fPyjets->K[3][iGlu+1] = -1;
1124 fPyjets->K[4][iGlu+1] = -1;
1125 SetMSTU(1,0);
1126 SetMSTU(2,0);
1127 //
1128 // Boost back
1129 //
1130 Pyrobo(iGlu + 1, iGlu + 2, 0., 0., bx, by, bz);
1131 }
4e383037 1132/*
1133 for (Int_t ig = iGlu; ig < iGlu+ish; ig++) {
1134 Double_t px, py, pz;
1135 px = fPyjets->P[0][ig];
1136 py = fPyjets->P[1][ig];
1137 pz = fPyjets->P[2][ig];
1138 TVector3 v(px, py, pz);
1139 v.RotateZ(-phiq[isys]);
1140 v.RotateY(-thetaq[isys]);
1141 Double_t pxs = v.X(); Double_t pys = v.Y(); Double_t pzs = v.Z();
1142 Double_t r = AliPythiaRndm::GetPythiaRandom()->Rndm();
1143 Double_t jtKick = 0.3 * TMath::Sqrt(-TMath::Log(r));
1144 if (ish == 2) jtKick = wjtKick[i] * TMath::Sqrt(-TMath::Log(r)) / TMath::Sqrt(2.);
1145 Double_t phiKick = 2. * TMath::Pi() * AliPythiaRndm::GetPythiaRandom()->Rndm();
1146 pxs += jtKick * TMath::Cos(phiKick);
1147 pys += jtKick * TMath::Sin(phiKick);
1148 TVector3 w(pxs, pys, pzs);
1149 w.RotateY(thetaq[isys]);
1150 w.RotateZ(phiq[isys]);
1151 fPyjets->P[0][ig] = w.X();
1152 fPyjets->P[1][ig] = w.Y();
1153 fPyjets->P[2][ig] = w.Z();
1154 fPyjets->P[2][ig] = w.Mag();
1155 }
1156*/
1157 } // kGluon
1158
6e90ad26 1159
4e383037 1160 // Check energy conservation
0f482ae4 1161 Double_t pxs = 0.;
1162 Double_t pys = 0.;
1163 Double_t pzs = 0.;
1164 Double_t es = 14000.;
1165
1166 for (Int_t i = 0; i < numpart; i++)
1167 {
1168 kst = fPyjets->K[0][i];
1169 if (kst != 1 && kst != 2) continue;
1170 pxs += fPyjets->P[0][i];
1171 pys += fPyjets->P[1][i];
1172 pzs += fPyjets->P[2][i];
1173 es -= fPyjets->P[3][i];
1174 }
1175 if (TMath::Abs(pxs) > 1.e-2 ||
1176 TMath::Abs(pys) > 1.e-2 ||
1177 TMath::Abs(pzs) > 1.e-1) {
1178 printf("%e %e %e %e\n", pxs, pys, pzs, es);
4e383037 1179// Fatal("Quench()", "4-Momentum non-conservation");
452af8c7 1180 }
4e383037 1181
1182 } // end quenching loop (systems)
6e90ad26 1183// Clean-up
0f482ae4 1184 for (Int_t i = 0; i < numpart; i++)
1185 {
4e383037 1186 imo = fPyjets->K[2][i];
1187 if (imo > 1000) {
1188 fPyjets->K[2][i] = fPyjets->K[2][i] % 1000;
1189 }
0f482ae4 1190 }
4e383037 1191// this->Pylist(1);
0f482ae4 1192} // end quench
90d7b703 1193