1 /**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
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 **************************************************************************/
18 #include "AliPythia.h"
19 #include "AliPythiaRndm.h"
20 #include "AliFastGlauber.h"
21 #include "AliQuenchingWeights.h"
22 #include "AliOmegaDalitz.h"
24 #include "TLorentzVector.h"
25 #include "PyquenCommon.h"
30 # define pyclus pyclus_
31 # define pycell pycell_
32 # define pyshow pyshow_
33 # define pyrobo pyrobo_
34 # define pyquen pyquen_
35 # define pyevnw pyevnw_
36 # define pyshowq pyshowq_
37 # define qpygin0 qpygin0_
38 # define pytune pytune_
39 # define py2ent py2ent_
42 # define pyclus PYCLUS
43 # define pycell PYCELL
44 # define pyrobo PYROBO
45 # define pyquen PYQUEN
46 # define pyevnw PYEVNW
47 # define pyshowq PYSHOWQ
48 # define qpygin0 QPYGIN0
49 # define pytune PYTUNE
50 # define py2ent PY2ENT
51 # define type_of_call _stdcall
54 extern "C" void type_of_call pyclus(Int_t & );
55 extern "C" void type_of_call pycell(Int_t & );
56 extern "C" void type_of_call pyshow(Int_t &, Int_t &, Double_t &);
57 extern "C" void type_of_call pyrobo(Int_t &, Int_t &, Double_t &, Double_t &, Double_t &, Double_t &, Double_t &);
58 extern "C" void type_of_call pyquen(Double_t &, Int_t &, Double_t &);
59 extern "C" void type_of_call pyevnw();
60 extern "C" void type_of_call pyshowq(Int_t &, Int_t &, Double_t &);
61 extern "C" void type_of_call pytune(Int_t &);
62 extern "C" void type_of_call py2ent(Int_t &, Int_t&, Int_t&, Double_t&);
63 extern "C" void type_of_call qpygin0();
64 //_____________________________________________________________________________
66 AliPythia* AliPythia::fgAliPythia=NULL;
68 AliPythia::AliPythia():
83 // Default Constructor
86 if (!AliPythiaRndm::GetPythiaRandom())
87 AliPythiaRndm::SetPythiaRandom(GetRandom());
89 fQuenchingWeights = 0;
91 for (i = 0; i < 501; i++) fDefMDCY[i] = 0;
92 for (i = 0; i < 2001; i++) fDefMDME[i] = 0;
93 for (i = 0; i < 4; i++) fZQuench[i] = 0;
96 AliPythia::AliPythia(const AliPythia& pythia):
109 fQuenchingWeights(0),
115 for (i = 0; i < 501; i++) fDefMDCY[i] = 0;
116 for (i = 0; i < 2001; i++) fDefMDME[i] = 0;
117 for (i = 0; i < 4; i++) fZQuench[i] = 0;
121 void AliPythia::ProcInit(Process_t process, Float_t energy, StrucFunc_t strucfunc, Int_t itune)
123 // Initialise the process to generate
124 if (!AliPythiaRndm::GetPythiaRandom())
125 AliPythiaRndm::SetPythiaRandom(GetRandom());
131 fStrucFunc = strucfunc;
132 //...Switch off decay of pi0, K0S, Lambda, Sigma+-, Xi0-, Omega-.
133 SetMDCY(Pycomp(111) ,1,0); // pi0
134 SetMDCY(Pycomp(310) ,1,0); // K0S
135 SetMDCY(Pycomp(3122),1,0); // kLambda
136 SetMDCY(Pycomp(3112),1,0); // sigma -
137 SetMDCY(Pycomp(3222),1,0); // sigma +
138 SetMDCY(Pycomp(3312),1,0); // xi -
139 SetMDCY(Pycomp(3322),1,0); // xi 0
140 SetMDCY(Pycomp(3334),1,0); // omega-
141 // Select structure function
143 SetMSTP(51, AliStructFuncType::PDFsetIndex(strucfunc));
144 // Particles produced in string fragmentation point directly to either of the two endpoints
145 // of the string (depending in the side they were generated from).
149 // Pythia initialisation for selected processes//
153 for (Int_t i=1; i<= 200; i++) {
156 // select charm production
159 case kPyOldUEQ2ordered: //Old underlying events with Q2 ordered QCD processes
160 // Multiple interactions on.
162 // Double Gaussian matter distribution.
168 // Reference energy for pT0 and energy rescaling pace.
171 // String drawing almost completely minimizes string length.
174 // ISR and FSR activity.
180 case kPyOldUEQ2ordered2:
181 // Old underlying events with Q2 ordered QCD processes
182 // Multiple interactions on.
184 // Double Gaussian matter distribution.
190 // Reference energy for pT0 and energy rescaling pace.
192 SetPARP(90,0.16); // here is the difference with kPyOldUEQ2ordered
193 // String drawing almost completely minimizes string length.
196 // ISR and FSR activity.
203 // Old production mechanism: Old Popcorn
206 // (D=2) Like MSTJ(12)=2 but added prod ofthe 1er rank baryon
208 // (D=1)see can be used to form baryons (BARYON JUNCTION)
214 // heavy quark masses
244 case kPyCharmUnforced:
253 case kPyBeautyUnforced:
263 // Minimum Bias pp-Collisions
266 // select Pythia min. bias model
268 SetMSUB(92,1); // single diffraction AB-->XB
269 SetMSUB(93,1); // single diffraction AB-->AX
270 SetMSUB(94,1); // double diffraction
271 SetMSUB(95,1); // low pt production
276 case kPyMbAtlasTuneMC09:
277 // Minimum Bias pp-Collisions
280 // select Pythia min. bias model
282 SetMSUB(92,1); // single diffraction AB-->XB
283 SetMSUB(93,1); // single diffraction AB-->AX
284 SetMSUB(94,1); // double diffraction
285 SetMSUB(95,1); // low pt production
290 case kPyMbWithDirectPhoton:
291 // Minimum Bias pp-Collisions with direct photon processes added
294 // select Pythia min. bias model
296 SetMSUB(92,1); // single diffraction AB-->XB
297 SetMSUB(93,1); // single diffraction AB-->AX
298 SetMSUB(94,1); // double diffraction
299 SetMSUB(95,1); // low pt production
312 // Minimum Bias pp-Collisions
315 // select Pythia min. bias model
317 SetMSUB(92,1); // single diffraction AB-->XB
318 SetMSUB(93,1); // single diffraction AB-->AX
319 SetMSUB(94,1); // double diffraction
320 SetMSUB(95,1); // low pt production
323 // Les Houches Working Group 05 Minimum Bias pp-Collisions: hep-ph/0604120
324 // -> Pythia 6.3 or above is needed
327 SetMSUB(92,1); // single diffraction AB-->XB
328 SetMSUB(93,1); // single diffraction AB-->AX
329 SetMSUB(94,1); // double diffraction
330 SetMSUB(95,1); // low pt production
332 SetMSTP(51,AliStructFuncType::PDFsetIndex(kCTEQ6ll)); // CTEQ6ll pdf
336 SetMSTP(81,1); // Multiple Interactions ON
337 SetMSTP(82,4); // Double Gaussian Model
340 SetPARP(82,2.3); // [GeV] PT_min at Ref. energy
341 SetPARP(83,0.5); // Core density in proton matter distribution (def.value)
342 SetPARP(84,0.5); // Core radius
343 SetPARP(85,0.9); // Regulates gluon prod. mechanism
344 SetPARP(90,0.2); // 2*epsilon (exponent in power law)
348 // Minimum Bias pp-Collisions
351 // select Pythia min. bias model
353 SetMSUB(95,1); // low pt production
360 SetMSTP(91,1);// Width (1=gaussian) primordial kT dist. inside hadrons
361 SetPARP(91,1.); // <kT^2> = PARP(91,1.)^2
362 SetPARP(93,5.); // Upper cut-off
364 SetPMAS(4,1,1.2); // Charm quark mass
365 SetPMAS(5,1,4.78); // Beauty quark mass
366 SetPARP(71,4.); // Defaut value
375 // Pythia Tune A (CDF)
377 SetPARP(67,2.5); // Regulates Initial State Radiation (value from best fit to D0 dijet analysis)
378 SetMSTP(82,4); // Double Gaussian Model
379 SetPARP(82,2.0); // [GeV] PT_min at Ref. energy
380 SetPARP(84,0.4); // Core radius
381 SetPARP(85,0.90) ; // Regulates gluon prod. mechanism
382 SetPARP(86,0.95); // Regulates gluon prod. mechanism
383 SetPARP(89,1800.); // [GeV] Ref. energy
384 SetPARP(90,0.25); // 2*epsilon (exponent in power law)
389 case kPyCharmPbPbMNR:
391 case kPyDPlusPbPbMNR:
392 case kPyDPlusStrangePbPbMNR:
393 // Tuning of Pythia parameters aimed to get a resonable agreement
394 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
395 // c-cbar single inclusive and double differential distributions.
396 // This parameter settings are meant to work with Pb-Pb collisions
397 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
398 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
399 // has to be set to 2.1GeV. Example in ConfigCharmPPR.C.
411 case kPyDPlusStrangepPbMNR:
412 // Tuning of Pythia parameters aimed to get a resonable agreement
413 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
414 // c-cbar single inclusive and double differential distributions.
415 // This parameter settings are meant to work with p-Pb collisions
416 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
417 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
418 // has to be set to 2.1GeV. Example in ConfigCharmPPR.C.
431 case kPyDPlusStrangeppMNR:
432 case kPyLambdacppMNR:
433 // Tuning of Pythia parameters aimed to get a resonable agreement
434 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
435 // c-cbar single inclusive and double differential distributions.
436 // This parameter settings are meant to work with pp collisions
437 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
438 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
439 // has to be set to 2.1GeV. Example in ConfigCharmPPR.C.
449 case kPyCharmppMNRwmi:
450 // Tuning of Pythia parameters aimed to get a resonable agreement
451 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
452 // c-cbar single inclusive and double differential distributions.
453 // This parameter settings are meant to work with pp collisions
454 // and with kCTEQ5L PDFs.
455 // Added multiple interactions according to ATLAS tune settings.
456 // To get a "reasonable" agreement with MNR results, events have to be
457 // generated with the minimum ptHard (AliGenPythia::SetPtHard)
459 // To get a "perfect" agreement with MNR results, events have to be
460 // generated in four ptHard bins with the following relative
476 case kPyBeautyPbPbMNR:
477 // Tuning of Pythia parameters aimed to get a resonable agreement
478 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
479 // b-bbar single inclusive and double differential distributions.
480 // This parameter settings are meant to work with Pb-Pb collisions
481 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
482 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
483 // has to be set to 2.75GeV. Example in ConfigBeautyPPR.C.
495 case kPyBeautypPbMNR:
496 // Tuning of Pythia parameters aimed to get a resonable agreement
497 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
498 // b-bbar single inclusive and double differential distributions.
499 // This parameter settings are meant to work with p-Pb collisions
500 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
501 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
502 // has to be set to 2.75GeV. Example in ConfigBeautyPPR.C.
515 // Tuning of Pythia parameters aimed to get a resonable agreement
516 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
517 // b-bbar single inclusive and double differential distributions.
518 // This parameter settings are meant to work with pp collisions
519 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
520 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
521 // has to be set to 2.75GeV. Example in ConfigBeautyPPR.C.
536 case kPyBeautyppMNRwmi:
537 // Tuning of Pythia parameters aimed to get a resonable agreement
538 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
539 // b-bbar single inclusive and double differential distributions.
540 // This parameter settings are meant to work with pp collisions
541 // and with kCTEQ5L PDFs.
542 // Added multiple interactions according to ATLAS tune settings.
543 // To get a "reasonable" agreement with MNR results, events have to be
544 // generated with the minimum ptHard (AliGenPythia::SetPtHard)
546 // To get a "perfect" agreement with MNR results, events have to be
547 // generated in four ptHard bins with the following relative
570 //Inclusive production of W+/-
576 // //f fbar -> gamma W+
583 // Initial/final parton shower on (Pythia default)
584 // With parton showers on we are generating "W inclusive process"
585 SetMSTP(61,1); //Initial QCD & QED showers on
586 SetMSTP(71,1); //Final QCD & QED showers on
592 //Inclusive production of Z
597 // // f fbar -> g Z/gamma
599 // // f fbar -> gamma Z/gamma
601 // // f g -> f Z/gamma
603 // // f gamma -> f Z/gamma
606 //only Z included, not gamma
609 // Initial/final parton shower on (Pythia default)
610 // With parton showers on we are generating "Z inclusive process"
611 SetMSTP(61,1); //Initial QCD & QED showers on
612 SetMSTP(71,1); //Final QCD & QED showers on
615 case kPyMBRSingleDiffraction:
616 case kPyMBRDoubleDiffraction:
617 case kPyMBRCentralDiffraction:
622 // For the case of jet production the following parameter setting
623 // limits the transverse momentum of secondary scatterings, due
624 // to multiple parton interactions, to be less than that of the
625 // primary interaction (see POWHEG Dijet paper arXiv:1012.3380
626 // [hep-ph] sec. 4.1 and also the PYTHIA Manual).
629 // maximum number of errors before pythia aborts (def=10)
631 // number of warnings printed on the shell
637 // number of warnings printed on the shell
646 if (itune > -1) Pytune(itune);
649 SetMSTP(41,1); // all resonance decays switched on
650 if (process == kPyJetsPWHG || process == kPyCharmPWHG || process == kPyBeautyPWHG) {
651 Initialize("USER","","",0.);
653 Initialize("CMS",fProjectile,fTarget,fEcms);
658 Int_t AliPythia::CheckedLuComp(Int_t kf)
660 // Check Lund particle code (for debugging)
662 printf("\n Lucomp kf,kc %d %d",kf,kc);
666 void AliPythia::SetNuclei(Int_t a1, Int_t a2, Int_t pdf)
668 // Treat protons as inside nuclei with mass numbers a1 and a2
669 // The MSTP array in the PYPARS common block is used to enable and
670 // select the nuclear structure functions.
671 // MSTP(52) : (D=1) choice of proton and nuclear structure-function library
672 // =1: internal PYTHIA acording to MSTP(51)
673 // =2: PDFLIB proton s.f., with MSTP(51) = 1000xNGROUP+NSET
674 // If the following mass number both not equal zero, nuclear corrections of the stf are used.
675 // MSTP(192) : Mass number of nucleus side 1
676 // MSTP(193) : Mass number of nucleus side 2
677 // MSTP(194) : Nuclear structure function: 0: EKS98 8:EPS08 9:EPS09LO 19:EPS09NLO
685 AliPythia* AliPythia::Instance()
687 // Set random number generator
691 fgAliPythia = new AliPythia();
696 void AliPythia::PrintParticles()
698 // Print list of particl properties
700 char* name = new char[16];
701 for (Int_t kf=0; kf<1000000; kf++) {
702 for (Int_t c = 1; c > -2; c-=2) {
703 Int_t kc = Pycomp(c*kf);
705 Float_t mass = GetPMAS(kc,1);
706 Float_t width = GetPMAS(kc,2);
707 Float_t tau = GetPMAS(kc,4);
713 printf("\n mass, width, tau: %6d %s %10.3f %10.3e %10.3e",
714 c*kf, name, mass, width, tau);
718 printf("\n Number of particles %d \n \n", np);
721 void AliPythia::ResetDecayTable()
723 // Set default values for pythia decay switches
725 for (i = 1; i < 501; i++) SetMDCY(i,1,fDefMDCY[i]);
726 for (i = 1; i < 2001; i++) SetMDME(i,1,fDefMDME[i]);
729 void AliPythia::SetDecayTable()
731 // Set default values for pythia decay switches
734 for (i = 1; i < 501; i++) fDefMDCY[i] = GetMDCY(i,1);
735 for (i = 1; i < 2001; i++) fDefMDME[i] = GetMDME(i,1);
738 void AliPythia::Pyclus(Int_t& njet)
740 // Call Pythia clustering algorithm
745 void AliPythia::Pycell(Int_t& njet)
747 // Call Pythia jet reconstruction algorithm
752 void AliPythia::Pyshow(Int_t ip1, Int_t ip2, Double_t qmax)
754 // Call Pythia jet reconstruction algorithm
756 pyshow(ip1, ip2, qmax);
759 void AliPythia::Pyrobo(Int_t imi, Int_t ima, Double_t the, Double_t phi, Double_t bex, Double_t bey, Double_t bez)
761 pyrobo(imi, ima, the, phi, bex, bey, bez);
764 void AliPythia::Pytune(Int_t itune)
768 C ITUNE NAME (detailed descriptions below)
769 C 0 Default : No settings changed => linked Pythia version's defaults.
770 C ====== Old UE, Q2-ordered showers ==========================================
771 C 100 A : Rick Field's CDF Tune A
772 C 101 AW : Rick Field's CDF Tune AW
773 C 102 BW : Rick Field's CDF Tune BW
774 C 103 DW : Rick Field's CDF Tune DW
775 C 104 DWT : Rick Field's CDF Tune DW with slower UE energy scaling
776 C 105 QW : Rick Field's CDF Tune QW (NB: needs CTEQ6.1M pdfs externally)
777 C 106 ATLAS-DC2: Arthur Moraes' (old) ATLAS tune (ATLAS DC2 / Rome)
778 C 107 ACR : Tune A modified with annealing CR
779 C 108 D6 : Rick Field's CDF Tune D6 (NB: needs CTEQ6L pdfs externally)
780 C 109 D6T : Rick Field's CDF Tune D6T (NB: needs CTEQ6L pdfs externally)
781 C ====== Intermediate Models =================================================
782 C 200 IM 1 : Intermediate model: new UE, Q2-ordered showers, annealing CR
783 C 201 APT : Tune A modified to use pT-ordered final-state showers
784 C ====== New UE, interleaved pT-ordered showers, annealing CR ================
785 C 300 S0 : Sandhoff-Skands Tune 0
786 C 301 S1 : Sandhoff-Skands Tune 1
787 C 302 S2 : Sandhoff-Skands Tune 2
788 C 303 S0A : S0 with "Tune A" UE energy scaling
789 C 304 NOCR : New UE "best try" without colour reconnections
790 C 305 Old : New UE, original (primitive) colour reconnections
791 C 306 ATLAS-CSC: Arthur Moraes' (new) ATLAS tune (needs CTEQ6L externally)
792 C ======= The Uppsala models =================================================
793 C ( NB! must be run with special modified Pythia 6.215 version )
794 C ( available from http://www.isv.uu.se/thep/MC/scigal/ )
795 C 400 GAL 0 : Generalized area-law model. Old parameters
796 C 401 SCI 0 : Soft-Colour-Interaction model. Old parameters
797 C 402 GAL 1 : Generalized area-law model. Tevatron MB retuned (Skands)
802 void AliPythia::Py2ent(Int_t idx, Int_t pdg1, Int_t pdg2, Double_t p){
803 // Inset 2-parton system at line idx
804 py2ent(idx, pdg1, pdg2, p);
808 void AliPythia::InitQuenching(Float_t cMin, Float_t cMax, Float_t k, Int_t iECMethod, Float_t zmax, Int_t ngmax)
811 // (1) The quenching model using quenching weights according to C. Salgado and U. Wiedemann
812 // (2) The nuclear geometry using the Glauber Model
815 fGlauber = AliFastGlauber::Instance();
817 fGlauber->SetCentralityClass(cMin, cMax);
819 fQuenchingWeights = new AliQuenchingWeights();
820 fQuenchingWeights->InitMult();
821 fQuenchingWeights->SetK(k);
822 fQuenchingWeights->SetECMethod(AliQuenchingWeights::kECMethod(iECMethod));
829 void AliPythia::Quench()
833 // Simple Jet Quenching routine:
834 // =============================
835 // The jet formed by all final state partons radiated by the parton created
836 // in the hard collisions is quenched by a factor (1-z) using light cone variables in
837 // the initial parton reference frame:
838 // (E + p_z)new = (1-z) (E + p_z)old
843 // The lost momentum is first balanced by one gluon with virtuality > 0.
844 // Subsequently the gluon splits to yield two gluons with E = p.
848 static Float_t eMean = 0.;
849 static Int_t icall = 0;
854 Int_t klast[4] = {-1, -1, -1, -1};
856 Int_t numpart = fPyjets->N;
857 Double_t px = 0., py = 0., pz = 0., e = 0., m = 0., p = 0., pt = 0., theta = 0., phi = 0.;
858 Double_t pxq[4], pyq[4], pzq[4], eq[4], yq[4], mq[4], pq[4], phiq[4], thetaq[4], ptq[4];
860 Double_t wjtKick[4] = {0., 0., 0., 0.};
866 // Sore information about Primary partons
869 // 0, 1 partons from hard scattering
870 // 2, 3 partons from initial state radiation
872 for (Int_t i = 2; i <= 7; i++) {
874 // Skip gluons that participate in hard scattering
875 if (i == 4 || i == 5) continue;
876 // Gluons from hard Scattering
877 if (i == 6 || i == 7) {
879 pxq[j] = fPyjets->P[0][i];
880 pyq[j] = fPyjets->P[1][i];
881 pzq[j] = fPyjets->P[2][i];
882 eq[j] = fPyjets->P[3][i];
883 mq[j] = fPyjets->P[4][i];
885 // Gluons from initial state radiation
887 // Obtain 4-momentum vector from difference between original parton and parton after gluon
888 // radiation. Energy is calculated independently because initial state radition does not
889 // conserve strictly momentum and energy for each partonic system independently.
891 // Not very clean. Should be improved !
895 pxq[j] = fPyjets->P[0][i] - fPyjets->P[0][i+2];
896 pyq[j] = fPyjets->P[1][i] - fPyjets->P[1][i+2];
897 pzq[j] = fPyjets->P[2][i] - fPyjets->P[2][i+2];
898 mq[j] = fPyjets->P[4][i];
899 eq[j] = TMath::Sqrt(pxq[j] * pxq[j] + pyq[j] * pyq[j] + pzq[j] * pzq[j] + mq[j] * mq[j]);
902 // Calculate some kinematic variables
904 yq[j] = 0.5 * TMath::Log((eq[j] + pzq[j] + 1.e-14) / (eq[j] - pzq[j] + 1.e-14));
905 pq[j] = TMath::Sqrt(pxq[j] * pxq[j] + pyq[j] * pyq[j] + pzq[j] * pzq[j]);
906 phiq[j] = TMath::Pi()+TMath::ATan2(-pyq[j], -pxq[j]);
907 ptq[j] = TMath::Sqrt(pxq[j] * pxq[j] + pyq[j] * pyq[j]);
908 thetaq[j] = TMath::ATan2(ptq[j], pzq[j]);
909 qPdg[j] = fPyjets->K[1][i];
915 fGlauber->GetI0I1ForPythiaAndXY(4, phiq, int0, int1, fXJet, fYJet, 15.);
917 for (Int_t j = 0; j < 4; j++) {
919 // Quench only central jets and with E > 10.
923 Int_t itype = (qPdg[j] == 21) ? 2 : 1;
924 Double_t eloss = fQuenchingWeights->GetELossRandomKFast(itype, int0[j], int1[j], eq[j]);
926 if (TMath::Abs(yq[j]) > 2.5 || eq[j] < 10.) {
929 if (eq[j] > 40. && TMath::Abs(yq[j]) < 0.5) {
935 Double_t l = fQuenchingWeights->CalcLk(int0[j], int1[j]);
936 wjtKick[j] = TMath::Sqrt(l * fQuenchingWeights->CalcQk(int0[j], int1[j]));
938 // Fractional energy loss
939 fZQuench[j] = eloss / eq[j];
941 // Avoid complete loss
943 if (fZQuench[j] > fZmax) fZQuench[j] = fZmax;
945 // Some debug printing
948 // 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",
949 // j, itype, eq[j], phiq[j], l, eloss, wjtKick[j], eMean / Float_t(icall+1), yq[j]);
951 // fZQuench[j] = 0.8;
952 // while (fZQuench[j] >= 0.95) fZQuench[j] = gRandom->Exp(0.2);
955 quenched[j] = (fZQuench[j] > 0.01);
960 Double_t pNew[1000][4];
967 for (Int_t isys = 0; isys < 4; isys++) {
968 // Skip to next system if not quenched.
969 if (!quenched[isys]) continue;
971 nGluon[isys] = 1 + Int_t(fZQuench[isys] / (1. - fZQuench[isys]));
972 if (nGluon[isys] > fNGmax) nGluon[isys] = fNGmax;
973 zquench[isys] = 1. - TMath::Power(1. - fZQuench[isys], 1./Double_t(nGluon[isys]));
974 wjtKick[isys] = wjtKick[isys] / TMath::Sqrt(Double_t(nGluon[isys]));
980 Double_t pg[4] = {0., 0., 0., 0.};
983 // Loop on radiation events
985 for (Int_t iglu = 0; iglu < nGluon[isys]; iglu++) {
988 for (Int_t k = 0; k < 4; k++)
995 for (Int_t i = 0; i < numpart; i++)
997 imo = fPyjets->K[2][i];
998 kst = fPyjets->K[0][i];
999 pdg = fPyjets->K[1][i];
1003 // Quarks and gluons only
1004 if (pdg != 21 && TMath::Abs(pdg) > 6) continue;
1005 // Particles from hard scattering only
1007 if (imo > 8 && imo < 1000) imo = fPyjets->K[2][imo - 1];
1008 Int_t imom = imo % 1000;
1009 if ((isys == 0 || isys == 1) && ((imom != (isys + 7)))) continue;
1010 if ((isys == 2 || isys == 3) && ((imom != (isys + 1)))) continue;
1013 // Skip comment lines
1014 if (kst != 1 && kst != 2) continue;
1017 px = fPyjets->P[0][i];
1018 py = fPyjets->P[1][i];
1019 pz = fPyjets->P[2][i];
1020 e = fPyjets->P[3][i];
1021 m = fPyjets->P[4][i];
1022 pt = TMath::Sqrt(px * px + py * py);
1023 p = TMath::Sqrt(px * px + py * py + pz * pz);
1024 phi = TMath::Pi() + TMath::ATan2(-py, -px);
1025 theta = TMath::ATan2(pt, pz);
1028 // Save 4-momentum sum for balancing
1039 // Fractional energy loss
1040 Double_t z = zquench[index];
1043 // Don't fully quench radiated gluons
1046 // This small factor makes sure that the gluons are not too close in phase space to avoid recombination
1051 // printf("z: %d %f\n", imo, z);
1058 // Transform into frame in which initial parton is along z-axis
1060 TVector3 v(px, py, pz);
1061 v.RotateZ(-phiq[index]); v.RotateY(-thetaq[index]);
1062 Double_t pxs = v.X(); Double_t pys = v.Y(); Double_t pl = v.Z();
1064 Double_t jt = TMath::Sqrt(pxs * pxs + pys * pys);
1065 Double_t mt2 = jt * jt + m * m;
1068 // Kinematic limit on z
1070 if (m > 0.) zmax = 1. - m / TMath::Sqrt(m * m + jt * jt);
1072 // Change light-cone kinematics rel. to initial parton
1074 Double_t eppzOld = e + pl;
1075 Double_t empzOld = e - pl;
1077 Double_t eppzNew = (1. - z) * eppzOld;
1078 Double_t empzNew = empzOld - mt2 * z / eppzOld;
1079 Double_t eNew = 0.5 * (eppzNew + empzNew);
1080 Double_t plNew = 0.5 * (eppzNew - empzNew);
1084 // if mt very small (or sometimes even < 0 for numerical reasons) set it to 0
1085 Double_t mt2New = eppzNew * empzNew;
1086 if (mt2New < 1.e-8) mt2New = 0.;
1088 if (m * m > mt2New) {
1090 // This should not happen
1092 Fatal("Quench()", "This should never happen %e %e %e!", m, eppzNew, empzNew);
1095 jtNew = TMath::Sqrt(mt2New - m * m);
1098 // If pT is to small (probably a leading massive particle) we scale only the energy
1099 // This can cause negative masses of the radiated gluon
1100 // Let's hope for the best ...
1102 eNew = TMath::Sqrt(plNew * plNew + mt2);
1106 // Calculate new px, py
1112 pxNew = jtNew / jt * pxs;
1113 pyNew = jtNew / jt * pys;
1115 // Double_t dpx = pxs - pxNew;
1116 // Double_t dpy = pys - pyNew;
1117 // Double_t dpz = pl - plNew;
1118 // Double_t de = e - eNew;
1119 // Double_t dmass2 = de * de - dpx * dpx - dpy * dpy - dpz * dpz;
1120 // printf("New mass (1) %e %e %e %e %e %e %e \n", dmass2, jt, jtNew, pl, plNew, e, eNew);
1121 // printf("New mass (2) %e %e \n", pxNew, pyNew);
1125 TVector3 w(pxNew, pyNew, plNew);
1126 w.RotateY(thetaq[index]); w.RotateZ(phiq[index]);
1127 pxNew = w.X(); pyNew = w.Y(); plNew = w.Z();
1129 p1[index][0] += pxNew;
1130 p1[index][1] += pyNew;
1131 p1[index][2] += plNew;
1132 p1[index][3] += eNew;
1134 // Updated 4-momentum vectors
1136 pNew[icount][0] = pxNew;
1137 pNew[icount][1] = pyNew;
1138 pNew[icount][2] = plNew;
1139 pNew[icount][3] = eNew;
1144 // Check if there was phase-space for quenching
1147 if (icount == 0) quenched[isys] = kFALSE;
1148 if (!quenched[isys]) break;
1150 for (Int_t j = 0; j < 4; j++)
1152 p2[isys][j] = p0[isys][j] - p1[isys][j];
1154 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];
1155 if (p2[isys][4] > 0.) {
1156 p2[isys][4] = TMath::Sqrt(p2[isys][4]);
1159 printf("Warning negative mass squared in system %d %f ! \n", isys, zquench[isys]);
1160 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]);
1161 if (p2[isys][4] < -0.01) {
1162 printf("Negative mass squared !\n");
1163 // Here we have to put the gluon back to mass shell
1164 // This will lead to a small energy imbalance
1166 p2[isys][3] = TMath::Sqrt(p2[isys][0] * p2[isys][0] + p2[isys][1] * p2[isys][1] + p2[isys][2] * p2[isys][2]);
1175 printf("zHeavy lowered to %f\n", zHeavy);
1176 if (zHeavy < 0.01) {
1177 printf("No success ! \n");
1179 quenched[isys] = kFALSE;
1183 } // iteration on z (while)
1185 // Update event record
1186 for (Int_t k = 0; k < icount; k++) {
1187 // 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] );
1188 fPyjets->P[0][kNew[k]] = pNew[k][0];
1189 fPyjets->P[1][kNew[k]] = pNew[k][1];
1190 fPyjets->P[2][kNew[k]] = pNew[k][2];
1191 fPyjets->P[3][kNew[k]] = pNew[k][3];
1198 if (!quenched[isys]) continue;
1200 // Last parton from shower i
1201 Int_t in = klast[isys];
1203 // Continue if no parton in shower i selected
1204 if (in == -1) continue;
1206 // If this is the second initial parton and it is behind the first move pointer by previous ish
1207 if (isys == 1 && klast[1] > klast[0]) in += ish;
1212 // How many additional gluons will be generated
1214 if (p2[isys][4] > 0.05) ish = 2;
1216 // Position of gluons
1218 if (iglu == 0) igMin = iGlu;
1221 (fPyjets->N) += ish;
1224 fPyjets->P[0][iGlu] = p2[isys][0];
1225 fPyjets->P[1][iGlu] = p2[isys][1];
1226 fPyjets->P[2][iGlu] = p2[isys][2];
1227 fPyjets->P[3][iGlu] = p2[isys][3];
1228 fPyjets->P[4][iGlu] = p2[isys][4];
1230 fPyjets->K[0][iGlu] = 1;
1231 if (iglu == nGluon[isys] - 1) fPyjets->K[0][iGlu] = 1;
1232 fPyjets->K[1][iGlu] = 21;
1233 fPyjets->K[2][iGlu] = fPyjets->K[2][in] + 1000;
1234 fPyjets->K[3][iGlu] = -1;
1235 fPyjets->K[4][iGlu] = -1;
1237 pg[0] += p2[isys][0];
1238 pg[1] += p2[isys][1];
1239 pg[2] += p2[isys][2];
1240 pg[3] += p2[isys][3];
1243 // Split gluon in rest frame.
1245 Double_t bx = p2[isys][0] / p2[isys][3];
1246 Double_t by = p2[isys][1] / p2[isys][3];
1247 Double_t bz = p2[isys][2] / p2[isys][3];
1248 Double_t pst = p2[isys][4] / 2.;
1250 // Isotropic decay ????
1251 Double_t cost = 2. * gRandom->Rndm() - 1.;
1252 Double_t sint = TMath::Sqrt((1.-cost)*(1.+cost));
1253 Double_t phis = 2. * TMath::Pi() * gRandom->Rndm();
1255 Double_t pz1 = pst * cost;
1256 Double_t pz2 = -pst * cost;
1257 Double_t pt1 = pst * sint;
1258 Double_t pt2 = -pst * sint;
1259 Double_t px1 = pt1 * TMath::Cos(phis);
1260 Double_t py1 = pt1 * TMath::Sin(phis);
1261 Double_t px2 = pt2 * TMath::Cos(phis);
1262 Double_t py2 = pt2 * TMath::Sin(phis);
1264 fPyjets->P[0][iGlu] = px1;
1265 fPyjets->P[1][iGlu] = py1;
1266 fPyjets->P[2][iGlu] = pz1;
1267 fPyjets->P[3][iGlu] = pst;
1268 fPyjets->P[4][iGlu] = 0.;
1270 fPyjets->K[0][iGlu] = 1 ;
1271 fPyjets->K[1][iGlu] = 21;
1272 fPyjets->K[2][iGlu] = fPyjets->K[2][in] + 1000;
1273 fPyjets->K[3][iGlu] = -1;
1274 fPyjets->K[4][iGlu] = -1;
1276 fPyjets->P[0][iGlu+1] = px2;
1277 fPyjets->P[1][iGlu+1] = py2;
1278 fPyjets->P[2][iGlu+1] = pz2;
1279 fPyjets->P[3][iGlu+1] = pst;
1280 fPyjets->P[4][iGlu+1] = 0.;
1282 fPyjets->K[0][iGlu+1] = 1;
1283 if (iglu == nGluon[isys] - 1) fPyjets->K[0][iGlu+1] = 1;
1284 fPyjets->K[1][iGlu+1] = 21;
1285 fPyjets->K[2][iGlu+1] = fPyjets->K[2][in] + 1000;
1286 fPyjets->K[3][iGlu+1] = -1;
1287 fPyjets->K[4][iGlu+1] = -1;
1293 Pyrobo(iGlu + 1, iGlu + 2, 0., 0., bx, by, bz);
1296 for (Int_t ig = iGlu; ig < iGlu+ish; ig++) {
1297 Double_t px, py, pz;
1298 px = fPyjets->P[0][ig];
1299 py = fPyjets->P[1][ig];
1300 pz = fPyjets->P[2][ig];
1301 TVector3 v(px, py, pz);
1302 v.RotateZ(-phiq[isys]);
1303 v.RotateY(-thetaq[isys]);
1304 Double_t pxs = v.X(); Double_t pys = v.Y(); Double_t pzs = v.Z();
1305 Double_t r = AliPythiaRndm::GetPythiaRandom()->Rndm();
1306 Double_t jtKick = 0.3 * TMath::Sqrt(-TMath::Log(r));
1307 if (ish == 2) jtKick = wjtKick[i] * TMath::Sqrt(-TMath::Log(r)) / TMath::Sqrt(2.);
1308 Double_t phiKick = 2. * TMath::Pi() * AliPythiaRndm::GetPythiaRandom()->Rndm();
1309 pxs += jtKick * TMath::Cos(phiKick);
1310 pys += jtKick * TMath::Sin(phiKick);
1311 TVector3 w(pxs, pys, pzs);
1312 w.RotateY(thetaq[isys]);
1313 w.RotateZ(phiq[isys]);
1314 fPyjets->P[0][ig] = w.X();
1315 fPyjets->P[1][ig] = w.Y();
1316 fPyjets->P[2][ig] = w.Z();
1317 fPyjets->P[2][ig] = w.Mag();
1323 // Check energy conservation
1327 Double_t es = 14000.;
1329 for (Int_t i = 0; i < numpart; i++)
1331 kst = fPyjets->K[0][i];
1332 if (kst != 1 && kst != 2) continue;
1333 pxs += fPyjets->P[0][i];
1334 pys += fPyjets->P[1][i];
1335 pzs += fPyjets->P[2][i];
1336 es -= fPyjets->P[3][i];
1338 if (TMath::Abs(pxs) > 1.e-2 ||
1339 TMath::Abs(pys) > 1.e-2 ||
1340 TMath::Abs(pzs) > 1.e-1) {
1341 printf("%e %e %e %e\n", pxs, pys, pzs, es);
1342 // Fatal("Quench()", "4-Momentum non-conservation");
1345 } // end quenching loop (systems)
1347 for (Int_t i = 0; i < numpart; i++)
1349 imo = fPyjets->K[2][i];
1351 fPyjets->K[2][i] = fPyjets->K[2][i] % 1000;
1358 void AliPythia::Pyquen(Double_t a, Int_t ibf, Double_t b)
1360 // Igor Lokthine's quenching routine
1361 // http://lokhtin.web.cern.ch/lokhtin/pyquen/pyquen.txt
1366 void AliPythia::SetPyquenParameters(Double_t t0, Double_t tau0, Int_t nf, Int_t iengl, Int_t iangl)
1368 // Set the parameters for the PYQUEN package.
1369 // See comments in PyquenCommon.h
1375 PYQPAR.iengl = iengl;
1376 PYQPAR.iangl = iangl;
1380 void AliPythia::Pyevnw()
1382 // New multiple interaction scenario
1386 void AliPythia::Pyshowq(Int_t ip1, Int_t ip2, Double_t qmax)
1388 // Call medium-modified Pythia jet reconstruction algorithm
1390 pyshowq(ip1, ip2, qmax);
1392 void AliPythia::Qpygin0()
1394 // New multiple interaction scenario
1398 void AliPythia::GetQuenchingParameters(Double_t& xp, Double_t& yp, Double_t z[4])
1400 // Return event specific quenching parameters
1403 for (Int_t i = 0; i < 4; i++) z[i] = fZQuench[i];
1407 void AliPythia::ConfigHeavyFlavor()
1410 // Default configuration for Heavy Flavor production
1412 // All QCD processes
1418 // No multiple interactions
1423 // Initial/final parton shower on (Pythia default)
1427 // 2nd order alpha_s
1435 void AliPythia::AtlasTuning()
1438 // Configuration for the ATLAS tuning
1439 if (fItune > -1) return;
1440 printf("ATLAS TUNE \n");
1442 SetMSTP(51, AliStructFuncType::PDFsetIndex(kCTEQ5L)); // CTEQ5L pdf
1443 SetMSTP(81,1); // Multiple Interactions ON
1444 SetMSTP(82,4); // Double Gaussian Model
1445 SetPARP(81,1.9); // Min. pt for multiple interactions (default in 6.2-14)
1446 SetPARP(82,1.8); // [GeV] PT_min at Ref. energy
1447 SetPARP(89,1000.); // [GeV] Ref. energy
1448 SetPARP(90,0.16); // 2*epsilon (exponent in power law)
1449 SetPARP(83,0.5); // Core density in proton matter distribution (def.value)
1450 SetPARP(84,0.5); // Core radius
1451 SetPARP(85,0.33); // Regulates gluon prod. mechanism
1452 SetPARP(86,0.66); // Regulates gluon prod. mechanism
1453 SetPARP(67,1); // Regulates Initial State Radiation
1456 void AliPythia::AtlasTuningMC09()
1459 // Configuration for the ATLAS tuning
1460 if (fItune > -1) return;
1461 printf("ATLAS New TUNE MC09\n");
1462 SetMSTP(81,21); // treatment for MI, ISR, FSR and beam remnants: MI on, new model
1463 SetMSTP(82, 4); // Double Gaussian Model
1464 SetMSTP(52, 2); // External PDF
1465 SetMSTP(51, 20650); // MRST LO*
1468 SetMSTP(70, 0); // (was 2: def manual 1, def code 0) virtuality scale for ISR
1469 SetMSTP(72, 1); // (was 0: def 1) maximum scale for FSR
1470 SetMSTP(88, 1); // (was 0: def 1) strategy for qq junction to di-quark or baryon in beam remnant
1471 SetMSTP(90, 0); // (was 1: def 0) strategy of compensate the primordial kT
1473 SetPARP(78, 0.3); // the amount of color reconnection in the final state
1474 SetPARP(80, 0.1); // probability of color partons kicked out from beam remnant
1475 SetPARP(82, 2.3); // [GeV] PT_min at Ref. energy
1476 SetPARP(83, 0.8); // Core density in proton matter distribution (def.value)
1477 SetPARP(84, 0.7); // Core radius
1478 SetPARP(90, 0.25); // 2*epsilon (exponent in power law)
1479 SetPARJ(81, 0.29); // (was 0.14: def 0.29) Labmda value in running alpha_s for parton showers
1482 SetPARJ(41, 0.3); // a and b parameters of the symmm. Lund FF
1484 SetPARJ(46, 0.75); // mod. of the Lund FF for heavy end-point quarks
1485 SetPARP(89,1800.); // [GeV] Ref. energy
1488 AliPythia& AliPythia::operator=(const AliPythia& rhs)
1490 // Assignment operator
1495 void AliPythia::Copy(TObject&) const
1500 Fatal("Copy","Not implemented!\n");
1503 void AliPythia::DalitzDecays()
1507 // Replace all omega dalitz decays with the correct matrix element decays
1509 Int_t nt = fPyjets->N;
1510 for (Int_t i = 0; i < nt; i++) {
1511 if (fPyjets->K[1][i] != 223) continue;
1512 Int_t fd = fPyjets->K[3][i] - 1;
1513 Int_t ld = fPyjets->K[4][i] - 1;
1514 if (fd < 0) continue;
1515 if ((ld - fd) != 2) continue;
1516 if ((fPyjets->K[1][fd] != 111) ||
1517 ((TMath::Abs(fPyjets->K[1][fd+1]) != 11) && (TMath::Abs(fPyjets->K[1][fd+1]) != 13)))
1519 TLorentzVector omega(fPyjets->P[0][i], fPyjets->P[1][i], fPyjets->P[2][i], fPyjets->P[3][i]);
1520 Int_t pdg = TMath::Abs(fPyjets->K[1][fd+1]);
1521 fOmegaDalitz.Decay(pdg, &omega);
1522 for (Int_t j = 0; j < 3; j++) {
1523 for (Int_t k = 0; k < 4; k++) {
1524 TLorentzVector vec = (fOmegaDalitz.Products())[2-j];
1525 fPyjets->P[k][fd+j] = vec[k];