2 /**************************************************************************
3 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
5 * Author: The ALICE Off-line Project. *
6 * Contributors are mentioned in the code where appropriate. *
8 * Permission to use, copy, modify and distribute this software and its *
9 * documentation strictly for non-commercial purposes is hereby granted *
10 * without fee, provided that the above copyright notice appears in all *
11 * copies and that both the copyright notice and this permission notice *
12 * appear in the supporting documentation. The authors make no claims *
13 * about the suitability of this software for any purpose. It is *
14 * provided "as is" without express or implied warranty. *
15 **************************************************************************/
19 #include "AliPythia.h"
20 #include "AliPythiaRndm.h"
21 #include "AliFastGlauber.h"
22 #include "AliQuenchingWeights.h"
24 #include "PyquenCommon.h"
29 # define pyclus pyclus_
30 # define pycell pycell_
31 # define pyshow pyshow_
32 # define pyrobo pyrobo_
33 # define pyquen pyquen_
34 # define pyevnw pyevnw_
35 # define pyshowq pyshowq_
36 # define qpygin0 qpygin0_
37 # define pytune pytune_
38 # define py2ent py2ent_
41 # define pyclus PYCLUS
42 # define pycell PYCELL
43 # define pyrobo PYROBO
44 # define pyquen PYQUEN
45 # define pyevnw PYEVNW
46 # define pyshowq PYSHOWQ
47 # define qpygin0 QPYGIN0
48 # define pytune PYTUNE
49 # define py2ent PY2ENT
50 # define type_of_call _stdcall
53 extern "C" void type_of_call pyclus(Int_t & );
54 extern "C" void type_of_call pycell(Int_t & );
55 extern "C" void type_of_call pyshow(Int_t &, Int_t &, Double_t &);
56 extern "C" void type_of_call pyrobo(Int_t &, Int_t &, Double_t &, Double_t &, Double_t &, Double_t &, Double_t &);
57 extern "C" void type_of_call pyquen(Double_t &, Int_t &, Double_t &);
58 extern "C" void type_of_call pyevnw(){;}
59 extern "C" void type_of_call pyshowq(Int_t &, Int_t &, Double_t &);
60 extern "C" void type_of_call pytune(Int_t &);
61 extern "C" void type_of_call py2ent(Int_t &, Int_t&, Int_t&, Double_t&);
62 extern "C" void type_of_call qpygin0();
63 //_____________________________________________________________________________
65 AliPythia* AliPythia::fgAliPythia=NULL;
67 AliPythia::AliPythia():
79 // Default Constructor
82 if (!AliPythiaRndm::GetPythiaRandom())
83 AliPythiaRndm::SetPythiaRandom(GetRandom());
85 fQuenchingWeights = 0;
88 AliPythia::AliPythia(const AliPythia& pythia):
106 void AliPythia::ProcInit(Process_t process, Float_t energy, StrucFunc_t strucfunc, Int_t itune)
108 // Initialise the process to generate
109 if (!AliPythiaRndm::GetPythiaRandom())
110 AliPythiaRndm::SetPythiaRandom(GetRandom());
116 fStrucFunc = strucfunc;
117 //...Switch off decay of pi0, K0S, Lambda, Sigma+-, Xi0-, Omega-.
118 SetMDCY(Pycomp(111) ,1,0); // pi0
119 SetMDCY(Pycomp(310) ,1,0); // K0S
120 SetMDCY(Pycomp(3122),1,0); // kLambda
121 SetMDCY(Pycomp(3112),1,0); // sigma -
122 SetMDCY(Pycomp(3212),1,0); // sigma 0
123 SetMDCY(Pycomp(3222),1,0); // sigma +
124 SetMDCY(Pycomp(3312),1,0); // xi -
125 SetMDCY(Pycomp(3322),1,0); // xi 0
126 SetMDCY(Pycomp(3334),1,0); // omega-
127 // Select structure function
129 SetMSTP(51, AliStructFuncType::PDFsetIndex(strucfunc));
130 // Particles produced in string fragmentation point directly to either of the two endpoints
131 // of the string (depending in the side they were generated from).
135 // Pythia initialisation for selected processes//
139 for (Int_t i=1; i<= 200; i++) {
142 // select charm production
145 case kPyOldUEQ2ordered: //Old underlying events with Q2 ordered QCD processes
146 // Multiple interactions on.
148 // Double Gaussian matter distribution.
154 // Reference energy for pT0 and energy rescaling pace.
157 // String drawing almost completely minimizes string length.
160 // ISR and FSR activity.
166 case kPyOldUEQ2ordered2:
167 // Old underlying events with Q2 ordered QCD processes
168 // Multiple interactions on.
170 // Double Gaussian matter distribution.
176 // Reference energy for pT0 and energy rescaling pace.
178 SetPARP(90,0.16); // here is the difference with kPyOldUEQ2ordered
179 // String drawing almost completely minimizes string length.
182 // ISR and FSR activity.
189 // Old production mechanism: Old Popcorn
192 // (D=2) Like MSTJ(12)=2 but added prod ofthe 1er rank baryon
194 // (D=1)see can be used to form baryons (BARYON JUNCTION)
200 // heavy quark masses
230 case kPyCharmUnforced:
239 case kPyBeautyUnforced:
249 // Minimum Bias pp-Collisions
252 // select Pythia min. bias model
254 SetMSUB(92,1); // single diffraction AB-->XB
255 SetMSUB(93,1); // single diffraction AB-->AX
256 SetMSUB(94,1); // double diffraction
257 SetMSUB(95,1); // low pt production
262 case kPyMbAtlasTuneMC09:
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 kPyMbWithDirectPhoton:
277 // Minimum Bias pp-Collisions with direct photon processes added
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
298 // Minimum Bias pp-Collisions
301 // select Pythia min. bias model
303 SetMSUB(92,1); // single diffraction AB-->XB
304 SetMSUB(93,1); // single diffraction AB-->AX
305 SetMSUB(94,1); // double diffraction
306 SetMSUB(95,1); // low pt production
309 // Les Houches Working Group 05 Minimum Bias pp-Collisions: hep-ph/0604120
310 // -> Pythia 6.3 or above is needed
313 SetMSUB(92,1); // single diffraction AB-->XB
314 SetMSUB(93,1); // single diffraction AB-->AX
315 SetMSUB(94,1); // double diffraction
316 SetMSUB(95,1); // low pt production
318 SetMSTP(51,AliStructFuncType::PDFsetIndex(kCTEQ6ll)); // CTEQ6ll pdf
322 SetMSTP(81,1); // Multiple Interactions ON
323 SetMSTP(82,4); // Double Gaussian Model
326 SetPARP(82,2.3); // [GeV] PT_min at Ref. energy
327 SetPARP(83,0.5); // Core density in proton matter distribution (def.value)
328 SetPARP(84,0.5); // Core radius
329 SetPARP(85,0.9); // Regulates gluon prod. mechanism
330 SetPARP(90,0.2); // 2*epsilon (exponent in power law)
334 // Minimum Bias pp-Collisions
337 // select Pythia min. bias model
339 SetMSUB(95,1); // low pt production
346 SetMSTP(91,1);// Width (1=gaussian) primordial kT dist. inside hadrons
347 SetPARP(91,1.); // <kT^2> = PARP(91,1.)^2
348 SetPARP(93,5.); // Upper cut-off
350 SetPMAS(4,1,1.2); // Charm quark mass
351 SetPMAS(5,1,4.78); // Beauty quark mass
352 SetPARP(71,4.); // Defaut value
361 // Pythia Tune A (CDF)
363 SetPARP(67,2.5); // Regulates Initial State Radiation (value from best fit to D0 dijet analysis)
364 SetMSTP(82,4); // Double Gaussian Model
365 SetPARP(82,2.0); // [GeV] PT_min at Ref. energy
366 SetPARP(84,0.4); // Core radius
367 SetPARP(85,0.90) ; // Regulates gluon prod. mechanism
368 SetPARP(86,0.95); // Regulates gluon prod. mechanism
369 SetPARP(89,1800.); // [GeV] Ref. energy
370 SetPARP(90,0.25); // 2*epsilon (exponent in power law)
375 case kPyCharmPbPbMNR:
377 case kPyDPlusPbPbMNR:
378 case kPyDPlusStrangePbPbMNR:
379 // Tuning of Pythia parameters aimed to get a resonable agreement
380 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
381 // c-cbar single inclusive and double differential distributions.
382 // This parameter settings are meant to work with Pb-Pb collisions
383 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
384 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
385 // has to be set to 2.1GeV. Example in ConfigCharmPPR.C.
397 case kPyDPlusStrangepPbMNR:
398 // Tuning of Pythia parameters aimed to get a resonable agreement
399 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
400 // c-cbar single inclusive and double differential distributions.
401 // This parameter settings are meant to work with p-Pb collisions
402 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
403 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
404 // has to be set to 2.1GeV. Example in ConfigCharmPPR.C.
417 case kPyDPlusStrangeppMNR:
418 // Tuning of Pythia parameters aimed to get a resonable agreement
419 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
420 // c-cbar single inclusive and double differential distributions.
421 // This parameter settings are meant to work with pp collisions
422 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
423 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
424 // has to be set to 2.1GeV. Example in ConfigCharmPPR.C.
434 case kPyCharmppMNRwmi:
435 // Tuning of Pythia parameters aimed to get a resonable agreement
436 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
437 // c-cbar single inclusive and double differential distributions.
438 // This parameter settings are meant to work with pp collisions
439 // and with kCTEQ5L PDFs.
440 // Added multiple interactions according to ATLAS tune settings.
441 // To get a "reasonable" agreement with MNR results, events have to be
442 // generated with the minimum ptHard (AliGenPythia::SetPtHard)
444 // To get a "perfect" agreement with MNR results, events have to be
445 // generated in four ptHard bins with the following relative
461 case kPyBeautyPbPbMNR:
462 // Tuning of Pythia parameters aimed to get a resonable agreement
463 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
464 // b-bbar single inclusive and double differential distributions.
465 // This parameter settings are meant to work with Pb-Pb collisions
466 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
467 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
468 // has to be set to 2.75GeV. Example in ConfigBeautyPPR.C.
480 case kPyBeautypPbMNR:
481 // Tuning of Pythia parameters aimed to get a resonable agreement
482 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
483 // b-bbar single inclusive and double differential distributions.
484 // This parameter settings are meant to work with p-Pb collisions
485 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
486 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
487 // has to be set to 2.75GeV. Example in ConfigBeautyPPR.C.
500 // Tuning of Pythia parameters aimed to get a resonable agreement
501 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
502 // b-bbar single inclusive and double differential distributions.
503 // This parameter settings are meant to work with pp collisions
504 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
505 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
506 // has to be set to 2.75GeV. Example in ConfigBeautyPPR.C.
521 case kPyBeautyppMNRwmi:
522 // Tuning of Pythia parameters aimed to get a resonable agreement
523 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
524 // b-bbar single inclusive and double differential distributions.
525 // This parameter settings are meant to work with pp collisions
526 // and with kCTEQ5L PDFs.
527 // Added multiple interactions according to ATLAS tune settings.
528 // To get a "reasonable" agreement with MNR results, events have to be
529 // generated with the minimum ptHard (AliGenPythia::SetPtHard)
531 // To get a "perfect" agreement with MNR results, events have to be
532 // generated in four ptHard bins with the following relative
555 //Inclusive production of W+/-
561 // //f fbar -> gamma W+
568 // Initial/final parton shower on (Pythia default)
569 // With parton showers on we are generating "W inclusive process"
570 SetMSTP(61,1); //Initial QCD & QED showers on
571 SetMSTP(71,1); //Final QCD & QED showers on
577 //Inclusive production of Z
582 // // f fbar -> g Z/gamma
584 // // f fbar -> gamma Z/gamma
586 // // f g -> f Z/gamma
588 // // f gamma -> f Z/gamma
591 //only Z included, not gamma
594 // Initial/final parton shower on (Pythia default)
595 // With parton showers on we are generating "Z inclusive process"
596 SetMSTP(61,1); //Initial QCD & QED showers on
597 SetMSTP(71,1); //Final QCD & QED showers on
606 if (itune > -1) Pytune(itune);
609 SetMSTP(41,1); // all resonance decays switched on
610 Initialize("CMS","p","p",fEcms);
614 Int_t AliPythia::CheckedLuComp(Int_t kf)
616 // Check Lund particle code (for debugging)
618 printf("\n Lucomp kf,kc %d %d",kf,kc);
622 void AliPythia::SetNuclei(Int_t a1, Int_t a2, Int_t pdf)
624 // Treat protons as inside nuclei with mass numbers a1 and a2
625 // The MSTP array in the PYPARS common block is used to enable and
626 // select the nuclear structure functions.
627 // MSTP(52) : (D=1) choice of proton and nuclear structure-function library
628 // =1: internal PYTHIA acording to MSTP(51)
629 // =2: PDFLIB proton s.f., with MSTP(51) = 1000xNGROUP+NSET
630 // If the following mass number both not equal zero, nuclear corrections of the stf are used.
631 // MSTP(192) : Mass number of nucleus side 1
632 // MSTP(193) : Mass number of nucleus side 2
633 // MSTP(194) : Nuclear structure function: 0: EKS98 1:EPS08
641 AliPythia* AliPythia::Instance()
643 // Set random number generator
647 fgAliPythia = new AliPythia();
652 void AliPythia::PrintParticles()
654 // Print list of particl properties
656 char* name = new char[16];
657 for (Int_t kf=0; kf<1000000; kf++) {
658 for (Int_t c = 1; c > -2; c-=2) {
659 Int_t kc = Pycomp(c*kf);
661 Float_t mass = GetPMAS(kc,1);
662 Float_t width = GetPMAS(kc,2);
663 Float_t tau = GetPMAS(kc,4);
669 printf("\n mass, width, tau: %6d %s %10.3f %10.3e %10.3e",
670 c*kf, name, mass, width, tau);
674 printf("\n Number of particles %d \n \n", np);
677 void AliPythia::ResetDecayTable()
679 // Set default values for pythia decay switches
681 for (i = 1; i < 501; i++) SetMDCY(i,1,fDefMDCY[i]);
682 for (i = 1; i < 2001; i++) SetMDME(i,1,fDefMDME[i]);
685 void AliPythia::SetDecayTable()
687 // Set default values for pythia decay switches
690 for (i = 1; i < 501; i++) fDefMDCY[i] = GetMDCY(i,1);
691 for (i = 1; i < 2001; i++) fDefMDME[i] = GetMDME(i,1);
694 void AliPythia::Pyclus(Int_t& njet)
696 // Call Pythia clustering algorithm
701 void AliPythia::Pycell(Int_t& njet)
703 // Call Pythia jet reconstruction algorithm
708 void AliPythia::Pyshow(Int_t ip1, Int_t ip2, Double_t qmax)
710 // Call Pythia jet reconstruction algorithm
712 pyshow(ip1, ip2, qmax);
715 void AliPythia::Pyrobo(Int_t imi, Int_t ima, Double_t the, Double_t phi, Double_t bex, Double_t bey, Double_t bez)
717 pyrobo(imi, ima, the, phi, bex, bey, bez);
720 void AliPythia::Pytune(Int_t itune)
724 C ITUNE NAME (detailed descriptions below)
725 C 0 Default : No settings changed => linked Pythia version's defaults.
726 C ====== Old UE, Q2-ordered showers ==========================================
727 C 100 A : Rick Field's CDF Tune A
728 C 101 AW : Rick Field's CDF Tune AW
729 C 102 BW : Rick Field's CDF Tune BW
730 C 103 DW : Rick Field's CDF Tune DW
731 C 104 DWT : Rick Field's CDF Tune DW with slower UE energy scaling
732 C 105 QW : Rick Field's CDF Tune QW (NB: needs CTEQ6.1M pdfs externally)
733 C 106 ATLAS-DC2: Arthur Moraes' (old) ATLAS tune (ATLAS DC2 / Rome)
734 C 107 ACR : Tune A modified with annealing CR
735 C 108 D6 : Rick Field's CDF Tune D6 (NB: needs CTEQ6L pdfs externally)
736 C 109 D6T : Rick Field's CDF Tune D6T (NB: needs CTEQ6L pdfs externally)
737 C ====== Intermediate Models =================================================
738 C 200 IM 1 : Intermediate model: new UE, Q2-ordered showers, annealing CR
739 C 201 APT : Tune A modified to use pT-ordered final-state showers
740 C ====== New UE, interleaved pT-ordered showers, annealing CR ================
741 C 300 S0 : Sandhoff-Skands Tune 0
742 C 301 S1 : Sandhoff-Skands Tune 1
743 C 302 S2 : Sandhoff-Skands Tune 2
744 C 303 S0A : S0 with "Tune A" UE energy scaling
745 C 304 NOCR : New UE "best try" without colour reconnections
746 C 305 Old : New UE, original (primitive) colour reconnections
747 C 306 ATLAS-CSC: Arthur Moraes' (new) ATLAS tune (needs CTEQ6L externally)
748 C ======= The Uppsala models =================================================
749 C ( NB! must be run with special modified Pythia 6.215 version )
750 C ( available from http://www.isv.uu.se/thep/MC/scigal/ )
751 C 400 GAL 0 : Generalized area-law model. Old parameters
752 C 401 SCI 0 : Soft-Colour-Interaction model. Old parameters
753 C 402 GAL 1 : Generalized area-law model. Tevatron MB retuned (Skands)
758 void AliPythia::Py2ent(Int_t idx, Int_t pdg1, Int_t pdg2, Double_t p){
759 // Inset 2-parton system at line idx
760 py2ent(idx, pdg1, pdg2, p);
764 void AliPythia::InitQuenching(Float_t cMin, Float_t cMax, Float_t k, Int_t iECMethod, Float_t zmax, Int_t ngmax)
767 // (1) The quenching model using quenching weights according to C. Salgado and U. Wiedemann
768 // (2) The nuclear geometry using the Glauber Model
771 fGlauber = AliFastGlauber::Instance();
773 fGlauber->SetCentralityClass(cMin, cMax);
775 fQuenchingWeights = new AliQuenchingWeights();
776 fQuenchingWeights->InitMult();
777 fQuenchingWeights->SetK(k);
778 fQuenchingWeights->SetECMethod(AliQuenchingWeights::kECMethod(iECMethod));
785 void AliPythia::Quench()
789 // Simple Jet Quenching routine:
790 // =============================
791 // The jet formed by all final state partons radiated by the parton created
792 // in the hard collisions is quenched by a factor (1-z) using light cone variables in
793 // the initial parton reference frame:
794 // (E + p_z)new = (1-z) (E + p_z)old
799 // The lost momentum is first balanced by one gluon with virtuality > 0.
800 // Subsequently the gluon splits to yield two gluons with E = p.
804 static Float_t eMean = 0.;
805 static Int_t icall = 0;
810 Int_t klast[4] = {-1, -1, -1, -1};
812 Int_t numpart = fPyjets->N;
813 Double_t px = 0., py = 0., pz = 0., e = 0., m = 0., p = 0., pt = 0., theta = 0., phi = 0.;
814 Double_t pxq[4], pyq[4], pzq[4], eq[4], yq[4], mq[4], pq[4], phiq[4], thetaq[4], ptq[4];
822 // Sore information about Primary partons
825 // 0, 1 partons from hard scattering
826 // 2, 3 partons from initial state radiation
828 for (Int_t i = 2; i <= 7; i++) {
830 // Skip gluons that participate in hard scattering
831 if (i == 4 || i == 5) continue;
832 // Gluons from hard Scattering
833 if (i == 6 || i == 7) {
835 pxq[j] = fPyjets->P[0][i];
836 pyq[j] = fPyjets->P[1][i];
837 pzq[j] = fPyjets->P[2][i];
838 eq[j] = fPyjets->P[3][i];
839 mq[j] = fPyjets->P[4][i];
841 // Gluons from initial state radiation
843 // Obtain 4-momentum vector from difference between original parton and parton after gluon
844 // radiation. Energy is calculated independently because initial state radition does not
845 // conserve strictly momentum and energy for each partonic system independently.
847 // Not very clean. Should be improved !
851 pxq[j] = fPyjets->P[0][i] - fPyjets->P[0][i+2];
852 pyq[j] = fPyjets->P[1][i] - fPyjets->P[1][i+2];
853 pzq[j] = fPyjets->P[2][i] - fPyjets->P[2][i+2];
854 mq[j] = fPyjets->P[4][i];
855 eq[j] = TMath::Sqrt(pxq[j] * pxq[j] + pyq[j] * pyq[j] + pzq[j] * pzq[j] + mq[j] * mq[j]);
858 // Calculate some kinematic variables
860 yq[j] = 0.5 * TMath::Log((eq[j] + pzq[j] + 1.e-14) / (eq[j] - pzq[j] + 1.e-14));
861 pq[j] = TMath::Sqrt(pxq[j] * pxq[j] + pyq[j] * pyq[j] + pzq[j] * pzq[j]);
862 phiq[j] = TMath::Pi()+TMath::ATan2(-pyq[j], -pxq[j]);
863 ptq[j] = TMath::Sqrt(pxq[j] * pxq[j] + pyq[j] * pyq[j]);
864 thetaq[j] = TMath::ATan2(ptq[j], pzq[j]);
865 qPdg[j] = fPyjets->K[1][i];
871 fGlauber->GetI0I1ForPythiaAndXY(4, phiq, int0, int1, fXJet, fYJet, 15.);
873 for (Int_t j = 0; j < 4; j++) {
875 // Quench only central jets and with E > 10.
879 Int_t itype = (qPdg[j] == 21) ? 2 : 1;
880 Double_t eloss = fQuenchingWeights->GetELossRandomKFast(itype, int0[j], int1[j], eq[j]);
882 if (TMath::Abs(yq[j]) > 2.5 || eq[j] < 10.) {
885 if (eq[j] > 40. && TMath::Abs(yq[j]) < 0.5) {
891 Double_t l = fQuenchingWeights->CalcLk(int0[j], int1[j]);
892 wjtKick[j] = TMath::Sqrt(l * fQuenchingWeights->CalcQk(int0[j], int1[j]));
894 // Fractional energy loss
895 fZQuench[j] = eloss / eq[j];
897 // Avoid complete loss
899 if (fZQuench[j] > fZmax) fZQuench[j] = fZmax;
901 // Some debug printing
904 // 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",
905 // j, itype, eq[j], phiq[j], l, eloss, wjtKick[j], eMean / Float_t(icall+1), yq[j]);
907 // fZQuench[j] = 0.8;
908 // while (fZQuench[j] >= 0.95) fZQuench[j] = gRandom->Exp(0.2);
911 quenched[j] = (fZQuench[j] > 0.01);
916 Double_t pNew[1000][4];
923 for (Int_t isys = 0; isys < 4; isys++) {
924 // Skip to next system if not quenched.
925 if (!quenched[isys]) continue;
927 nGluon[isys] = 1 + Int_t(fZQuench[isys] / (1. - fZQuench[isys]));
928 if (nGluon[isys] > fNGmax) nGluon[isys] = fNGmax;
929 zquench[isys] = 1. - TMath::Power(1. - fZQuench[isys], 1./Double_t(nGluon[isys]));
930 wjtKick[isys] = wjtKick[isys] / TMath::Sqrt(Double_t(nGluon[isys]));
936 Double_t pg[4] = {0., 0., 0., 0.};
939 // Loop on radiation events
941 for (Int_t iglu = 0; iglu < nGluon[isys]; iglu++) {
944 for (Int_t k = 0; k < 4; k++)
951 for (Int_t i = 0; i < numpart; i++)
953 imo = fPyjets->K[2][i];
954 kst = fPyjets->K[0][i];
955 pdg = fPyjets->K[1][i];
959 // Quarks and gluons only
960 if (pdg != 21 && TMath::Abs(pdg) > 6) continue;
961 // Particles from hard scattering only
963 if (imo > 8 && imo < 1000) imo = fPyjets->K[2][imo - 1];
964 Int_t imom = imo % 1000;
965 if ((isys == 0 || isys == 1) && ((imom != (isys + 7)))) continue;
966 if ((isys == 2 || isys == 3) && ((imom != (isys + 1)))) continue;
969 // Skip comment lines
970 if (kst != 1 && kst != 2) continue;
973 px = fPyjets->P[0][i];
974 py = fPyjets->P[1][i];
975 pz = fPyjets->P[2][i];
976 e = fPyjets->P[3][i];
977 m = fPyjets->P[4][i];
978 pt = TMath::Sqrt(px * px + py * py);
979 p = TMath::Sqrt(px * px + py * py + pz * pz);
980 phi = TMath::Pi() + TMath::ATan2(-py, -px);
981 theta = TMath::ATan2(pt, pz);
984 // Save 4-momentum sum for balancing
995 // Fractional energy loss
996 Double_t z = zquench[index];
999 // Don't fully quench radiated gluons
1002 // This small factor makes sure that the gluons are not too close in phase space to avoid recombination
1007 // printf("z: %d %f\n", imo, z);
1014 // Transform into frame in which initial parton is along z-axis
1016 TVector3 v(px, py, pz);
1017 v.RotateZ(-phiq[index]); v.RotateY(-thetaq[index]);
1018 Double_t pxs = v.X(); Double_t pys = v.Y(); Double_t pl = v.Z();
1020 Double_t jt = TMath::Sqrt(pxs * pxs + pys * pys);
1021 Double_t mt2 = jt * jt + m * m;
1024 // Kinematic limit on z
1026 if (m > 0.) zmax = 1. - m / TMath::Sqrt(m * m + jt * jt);
1028 // Change light-cone kinematics rel. to initial parton
1030 Double_t eppzOld = e + pl;
1031 Double_t empzOld = e - pl;
1033 Double_t eppzNew = (1. - z) * eppzOld;
1034 Double_t empzNew = empzOld - mt2 * z / eppzOld;
1035 Double_t eNew = 0.5 * (eppzNew + empzNew);
1036 Double_t plNew = 0.5 * (eppzNew - empzNew);
1040 // if mt very small (or sometimes even < 0 for numerical reasons) set it to 0
1041 Double_t mt2New = eppzNew * empzNew;
1042 if (mt2New < 1.e-8) mt2New = 0.;
1044 if (m * m > mt2New) {
1046 // This should not happen
1048 Fatal("Quench()", "This should never happen %e %e %e!", m, eppzNew, empzNew);
1051 jtNew = TMath::Sqrt(mt2New - m * m);
1054 // If pT is to small (probably a leading massive particle) we scale only the energy
1055 // This can cause negative masses of the radiated gluon
1056 // Let's hope for the best ...
1058 eNew = TMath::Sqrt(plNew * plNew + mt2);
1062 // Calculate new px, py
1068 pxNew = jtNew / jt * pxs;
1069 pyNew = jtNew / jt * pys;
1071 // Double_t dpx = pxs - pxNew;
1072 // Double_t dpy = pys - pyNew;
1073 // Double_t dpz = pl - plNew;
1074 // Double_t de = e - eNew;
1075 // Double_t dmass2 = de * de - dpx * dpx - dpy * dpy - dpz * dpz;
1076 // printf("New mass (1) %e %e %e %e %e %e %e \n", dmass2, jt, jtNew, pl, plNew, e, eNew);
1077 // printf("New mass (2) %e %e \n", pxNew, pyNew);
1081 TVector3 w(pxNew, pyNew, plNew);
1082 w.RotateY(thetaq[index]); w.RotateZ(phiq[index]);
1083 pxNew = w.X(); pyNew = w.Y(); plNew = w.Z();
1085 p1[index][0] += pxNew;
1086 p1[index][1] += pyNew;
1087 p1[index][2] += plNew;
1088 p1[index][3] += eNew;
1090 // Updated 4-momentum vectors
1092 pNew[icount][0] = pxNew;
1093 pNew[icount][1] = pyNew;
1094 pNew[icount][2] = plNew;
1095 pNew[icount][3] = eNew;
1100 // Check if there was phase-space for quenching
1103 if (icount == 0) quenched[isys] = kFALSE;
1104 if (!quenched[isys]) break;
1106 for (Int_t j = 0; j < 4; j++)
1108 p2[isys][j] = p0[isys][j] - p1[isys][j];
1110 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];
1111 if (p2[isys][4] > 0.) {
1112 p2[isys][4] = TMath::Sqrt(p2[isys][4]);
1115 printf("Warning negative mass squared in system %d %f ! \n", isys, zquench[isys]);
1116 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]);
1117 if (p2[isys][4] < -0.01) {
1118 printf("Negative mass squared !\n");
1119 // Here we have to put the gluon back to mass shell
1120 // This will lead to a small energy imbalance
1122 p2[isys][3] = TMath::Sqrt(p2[isys][0] * p2[isys][0] + p2[isys][1] * p2[isys][1] + p2[isys][2] * p2[isys][2]);
1131 printf("zHeavy lowered to %f\n", zHeavy);
1132 if (zHeavy < 0.01) {
1133 printf("No success ! \n");
1135 quenched[isys] = kFALSE;
1139 } // iteration on z (while)
1141 // Update event record
1142 for (Int_t k = 0; k < icount; k++) {
1143 // 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] );
1144 fPyjets->P[0][kNew[k]] = pNew[k][0];
1145 fPyjets->P[1][kNew[k]] = pNew[k][1];
1146 fPyjets->P[2][kNew[k]] = pNew[k][2];
1147 fPyjets->P[3][kNew[k]] = pNew[k][3];
1154 if (!quenched[isys]) continue;
1156 // Last parton from shower i
1157 Int_t in = klast[isys];
1159 // Continue if no parton in shower i selected
1160 if (in == -1) continue;
1162 // If this is the second initial parton and it is behind the first move pointer by previous ish
1163 if (isys == 1 && klast[1] > klast[0]) in += ish;
1168 // How many additional gluons will be generated
1170 if (p2[isys][4] > 0.05) ish = 2;
1172 // Position of gluons
1174 if (iglu == 0) igMin = iGlu;
1177 (fPyjets->N) += ish;
1180 fPyjets->P[0][iGlu] = p2[isys][0];
1181 fPyjets->P[1][iGlu] = p2[isys][1];
1182 fPyjets->P[2][iGlu] = p2[isys][2];
1183 fPyjets->P[3][iGlu] = p2[isys][3];
1184 fPyjets->P[4][iGlu] = p2[isys][4];
1186 fPyjets->K[0][iGlu] = 1;
1187 if (iglu == nGluon[isys] - 1) fPyjets->K[0][iGlu] = 1;
1188 fPyjets->K[1][iGlu] = 21;
1189 fPyjets->K[2][iGlu] = fPyjets->K[2][in] + 1000;
1190 fPyjets->K[3][iGlu] = -1;
1191 fPyjets->K[4][iGlu] = -1;
1193 pg[0] += p2[isys][0];
1194 pg[1] += p2[isys][1];
1195 pg[2] += p2[isys][2];
1196 pg[3] += p2[isys][3];
1199 // Split gluon in rest frame.
1201 Double_t bx = p2[isys][0] / p2[isys][3];
1202 Double_t by = p2[isys][1] / p2[isys][3];
1203 Double_t bz = p2[isys][2] / p2[isys][3];
1204 Double_t pst = p2[isys][4] / 2.;
1206 // Isotropic decay ????
1207 Double_t cost = 2. * gRandom->Rndm() - 1.;
1208 Double_t sint = TMath::Sqrt((1.-cost)*(1.+cost));
1209 Double_t phis = 2. * TMath::Pi() * gRandom->Rndm();
1211 Double_t pz1 = pst * cost;
1212 Double_t pz2 = -pst * cost;
1213 Double_t pt1 = pst * sint;
1214 Double_t pt2 = -pst * sint;
1215 Double_t px1 = pt1 * TMath::Cos(phis);
1216 Double_t py1 = pt1 * TMath::Sin(phis);
1217 Double_t px2 = pt2 * TMath::Cos(phis);
1218 Double_t py2 = pt2 * TMath::Sin(phis);
1220 fPyjets->P[0][iGlu] = px1;
1221 fPyjets->P[1][iGlu] = py1;
1222 fPyjets->P[2][iGlu] = pz1;
1223 fPyjets->P[3][iGlu] = pst;
1224 fPyjets->P[4][iGlu] = 0.;
1226 fPyjets->K[0][iGlu] = 1 ;
1227 fPyjets->K[1][iGlu] = 21;
1228 fPyjets->K[2][iGlu] = fPyjets->K[2][in] + 1000;
1229 fPyjets->K[3][iGlu] = -1;
1230 fPyjets->K[4][iGlu] = -1;
1232 fPyjets->P[0][iGlu+1] = px2;
1233 fPyjets->P[1][iGlu+1] = py2;
1234 fPyjets->P[2][iGlu+1] = pz2;
1235 fPyjets->P[3][iGlu+1] = pst;
1236 fPyjets->P[4][iGlu+1] = 0.;
1238 fPyjets->K[0][iGlu+1] = 1;
1239 if (iglu == nGluon[isys] - 1) fPyjets->K[0][iGlu+1] = 1;
1240 fPyjets->K[1][iGlu+1] = 21;
1241 fPyjets->K[2][iGlu+1] = fPyjets->K[2][in] + 1000;
1242 fPyjets->K[3][iGlu+1] = -1;
1243 fPyjets->K[4][iGlu+1] = -1;
1249 Pyrobo(iGlu + 1, iGlu + 2, 0., 0., bx, by, bz);
1252 for (Int_t ig = iGlu; ig < iGlu+ish; ig++) {
1253 Double_t px, py, pz;
1254 px = fPyjets->P[0][ig];
1255 py = fPyjets->P[1][ig];
1256 pz = fPyjets->P[2][ig];
1257 TVector3 v(px, py, pz);
1258 v.RotateZ(-phiq[isys]);
1259 v.RotateY(-thetaq[isys]);
1260 Double_t pxs = v.X(); Double_t pys = v.Y(); Double_t pzs = v.Z();
1261 Double_t r = AliPythiaRndm::GetPythiaRandom()->Rndm();
1262 Double_t jtKick = 0.3 * TMath::Sqrt(-TMath::Log(r));
1263 if (ish == 2) jtKick = wjtKick[i] * TMath::Sqrt(-TMath::Log(r)) / TMath::Sqrt(2.);
1264 Double_t phiKick = 2. * TMath::Pi() * AliPythiaRndm::GetPythiaRandom()->Rndm();
1265 pxs += jtKick * TMath::Cos(phiKick);
1266 pys += jtKick * TMath::Sin(phiKick);
1267 TVector3 w(pxs, pys, pzs);
1268 w.RotateY(thetaq[isys]);
1269 w.RotateZ(phiq[isys]);
1270 fPyjets->P[0][ig] = w.X();
1271 fPyjets->P[1][ig] = w.Y();
1272 fPyjets->P[2][ig] = w.Z();
1273 fPyjets->P[2][ig] = w.Mag();
1279 // Check energy conservation
1283 Double_t es = 14000.;
1285 for (Int_t i = 0; i < numpart; i++)
1287 kst = fPyjets->K[0][i];
1288 if (kst != 1 && kst != 2) continue;
1289 pxs += fPyjets->P[0][i];
1290 pys += fPyjets->P[1][i];
1291 pzs += fPyjets->P[2][i];
1292 es -= fPyjets->P[3][i];
1294 if (TMath::Abs(pxs) > 1.e-2 ||
1295 TMath::Abs(pys) > 1.e-2 ||
1296 TMath::Abs(pzs) > 1.e-1) {
1297 printf("%e %e %e %e\n", pxs, pys, pzs, es);
1298 // Fatal("Quench()", "4-Momentum non-conservation");
1301 } // end quenching loop (systems)
1303 for (Int_t i = 0; i < numpart; i++)
1305 imo = fPyjets->K[2][i];
1307 fPyjets->K[2][i] = fPyjets->K[2][i] % 1000;
1314 void AliPythia::Pyquen(Double_t a, Int_t ibf, Double_t b)
1316 // Igor Lokthine's quenching routine
1317 // http://lokhtin.web.cern.ch/lokhtin/pyquen/pyquen.txt
1322 void AliPythia::SetPyquenParameters(Double_t t0, Double_t tau0, Int_t nf, Int_t iengl, Int_t iangl)
1324 // Set the parameters for the PYQUEN package.
1325 // See comments in PyquenCommon.h
1331 PYQPAR.iengl = iengl;
1332 PYQPAR.iangl = iangl;
1336 void AliPythia::Pyevnw()
1338 // New multiple interaction scenario
1342 void AliPythia::Pyshowq(Int_t ip1, Int_t ip2, Double_t qmax)
1344 // Call medium-modified Pythia jet reconstruction algorithm
1346 pyshowq(ip1, ip2, qmax);
1348 void AliPythia::Qpygin0()
1350 // New multiple interaction scenario
1354 void AliPythia::GetQuenchingParameters(Double_t& xp, Double_t& yp, Double_t z[4])
1356 // Return event specific quenching parameters
1359 for (Int_t i = 0; i < 4; i++) z[i] = fZQuench[i];
1363 void AliPythia::ConfigHeavyFlavor()
1366 // Default configuration for Heavy Flavor production
1368 // All QCD processes
1372 // No multiple interactions
1376 // Initial/final parton shower on (Pythia default)
1380 // 2nd order alpha_s
1388 void AliPythia::AtlasTuning()
1391 // Configuration for the ATLAS tuning
1392 if (fItune > -1) return;
1393 printf("ATLAS TUNE \n");
1395 SetMSTP(51, AliStructFuncType::PDFsetIndex(kCTEQ5L)); // CTEQ5L pdf
1396 SetMSTP(81,1); // Multiple Interactions ON
1397 SetMSTP(82,4); // Double Gaussian Model
1398 SetPARP(81,1.9); // Min. pt for multiple interactions (default in 6.2-14)
1399 SetPARP(82,1.8); // [GeV] PT_min at Ref. energy
1400 SetPARP(89,1000.); // [GeV] Ref. energy
1401 SetPARP(90,0.16); // 2*epsilon (exponent in power law)
1402 SetPARP(83,0.5); // Core density in proton matter distribution (def.value)
1403 SetPARP(84,0.5); // Core radius
1404 SetPARP(85,0.33); // Regulates gluon prod. mechanism
1405 SetPARP(86,0.66); // Regulates gluon prod. mechanism
1406 SetPARP(67,1); // Regulates Initial State Radiation
1409 void AliPythia::AtlasTuning_MC09()
1412 // Configuration for the ATLAS tuning
1413 if (fItune > -1) return;
1414 printf("ATLAS New TUNE MC09\n");
1415 SetMSTP(81,21); // treatment for MI, ISR, FSR and beam remnants: MI on, new model
1416 SetMSTP(82, 4); // Double Gaussian Model
1417 SetMSTP(52, 2); // External PDF
1418 SetMSTP(51, 20650); // MRST LO*
1421 SetMSTP(70, 0); // (was 2: def manual 1, def code 0) virtuality scale for ISR
1422 SetMSTP(72, 1); // (was 0: def 1) maximum scale for FSR
1423 SetMSTP(88, 1); // (was 0: def 1) strategy for qq junction to di-quark or baryon in beam remnant
1424 SetMSTP(90, 0); // (was 1: def 0) strategy of compensate the primordial kT
1426 SetPARP(78, 0.3); // the amount of color reconnection in the final state
1427 SetPARP(80, 0.1); // probability of color partons kicked out from beam remnant
1428 SetPARP(82, 2.3); // [GeV] PT_min at Ref. energy
1429 SetPARP(83, 0.8); // Core density in proton matter distribution (def.value)
1430 SetPARP(84, 0.7); // Core radius
1431 SetPARP(90, 0.25); // 2*epsilon (exponent in power law)
1432 SetPARJ(81, 0.29); // (was 0.14: def 0.29) Labmda value in running alpha_s for parton showers
1435 SetPARJ(41, 0.3); // a and b parameters of the symmm. Lund FF
1437 SetPARJ(46, 0.75); // mod. of the Lund FF for heavy end-point quarks
1438 SetPARP(89,1800.); // [GeV] Ref. energy
1441 AliPythia& AliPythia::operator=(const AliPythia& rhs)
1443 // Assignment operator
1448 void AliPythia::Copy(TObject&) const
1453 Fatal("Copy","Not implemented!\n");