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"
25 #include "TLorentzVector.h"
26 #include "PyquenCommon.h"
31 # define pyclus pyclus_
32 # define pycell pycell_
33 # define pyshow pyshow_
34 # define pyrobo pyrobo_
35 # define pyquen pyquen_
36 # define pyevnw pyevnw_
37 # define pyshowq pyshowq_
38 # define qpygin0 qpygin0_
39 # define pytune pytune_
40 # define py2ent py2ent_
43 # define pyclus PYCLUS
44 # define pycell PYCELL
45 # define pyrobo PYROBO
46 # define pyquen PYQUEN
47 # define pyevnw PYEVNW
48 # define pyshowq PYSHOWQ
49 # define qpygin0 QPYGIN0
50 # define pytune PYTUNE
51 # define py2ent PY2ENT
52 # define type_of_call _stdcall
55 extern "C" void type_of_call pyclus(Int_t & );
56 extern "C" void type_of_call pycell(Int_t & );
57 extern "C" void type_of_call pyshow(Int_t &, Int_t &, Double_t &);
58 extern "C" void type_of_call pyrobo(Int_t &, Int_t &, Double_t &, Double_t &, Double_t &, Double_t &, Double_t &);
59 extern "C" void type_of_call pyquen(Double_t &, Int_t &, Double_t &);
60 extern "C" void type_of_call pyevnw();
61 extern "C" void type_of_call pyshowq(Int_t &, Int_t &, Double_t &);
62 extern "C" void type_of_call pytune(Int_t &);
63 extern "C" void type_of_call py2ent(Int_t &, Int_t&, Int_t&, Double_t&);
64 extern "C" void type_of_call qpygin0();
65 //_____________________________________________________________________________
67 AliPythia* AliPythia::fgAliPythia=NULL;
69 AliPythia::AliPythia():
84 // Default Constructor
87 if (!AliPythiaRndm::GetPythiaRandom())
88 AliPythiaRndm::SetPythiaRandom(GetRandom());
90 fQuenchingWeights = 0;
92 for (i = 0; i < 501; i++) fDefMDCY[i] = 0;
93 for (i = 0; i < 2001; i++) fDefMDME[i] = 0;
94 for (i = 0; i < 4; i++) fZQuench[i] = 0;
97 AliPythia::AliPythia(const AliPythia& pythia):
110 fQuenchingWeights(0),
116 for (i = 0; i < 501; i++) fDefMDCY[i] = 0;
117 for (i = 0; i < 2001; i++) fDefMDME[i] = 0;
118 for (i = 0; i < 4; i++) fZQuench[i] = 0;
122 void AliPythia::ProcInit(Process_t process, Float_t energy, StrucFunc_t strucfunc, Int_t itune)
124 // Initialise the process to generate
125 if (!AliPythiaRndm::GetPythiaRandom())
126 AliPythiaRndm::SetPythiaRandom(GetRandom());
132 fStrucFunc = strucfunc;
133 //...Switch off decay of pi0, K0S, Lambda, Sigma+-, Xi0-, Omega-.
134 SetMDCY(Pycomp(111) ,1,0); // pi0
135 SetMDCY(Pycomp(310) ,1,0); // K0S
136 SetMDCY(Pycomp(3122),1,0); // kLambda
137 SetMDCY(Pycomp(3112),1,0); // sigma -
138 SetMDCY(Pycomp(3222),1,0); // sigma +
139 SetMDCY(Pycomp(3312),1,0); // xi -
140 SetMDCY(Pycomp(3322),1,0); // xi 0
141 SetMDCY(Pycomp(3334),1,0); // omega-
142 // Select structure function
144 SetMSTP(51, AliStructFuncType::PDFsetIndex(strucfunc));
145 // Particles produced in string fragmentation point directly to either of the two endpoints
146 // of the string (depending in the side they were generated from).
150 // Pythia initialisation for selected processes//
154 for (Int_t i=1; i<= 200; i++) {
157 // select charm production
160 case kPyOldUEQ2ordered: //Old underlying events with Q2 ordered QCD processes
161 // Multiple interactions on.
163 // Double Gaussian matter distribution.
169 // Reference energy for pT0 and energy rescaling pace.
172 // String drawing almost completely minimizes string length.
175 // ISR and FSR activity.
181 case kPyOldUEQ2ordered2:
182 // Old underlying events with Q2 ordered QCD processes
183 // Multiple interactions on.
185 // Double Gaussian matter distribution.
191 // Reference energy for pT0 and energy rescaling pace.
193 SetPARP(90,0.16); // here is the difference with kPyOldUEQ2ordered
194 // String drawing almost completely minimizes string length.
197 // ISR and FSR activity.
204 // Old production mechanism: Old Popcorn
207 // (D=2) Like MSTJ(12)=2 but added prod ofthe 1er rank baryon
209 // (D=1)see can be used to form baryons (BARYON JUNCTION)
215 // heavy quark masses
245 case kPyCharmUnforced:
254 case kPyBeautyUnforced:
264 // Minimum Bias pp-Collisions
267 // select Pythia min. bias model
269 SetMSUB(92,1); // single diffraction AB-->XB
270 SetMSUB(93,1); // single diffraction AB-->AX
271 SetMSUB(94,1); // double diffraction
272 SetMSUB(95,1); // low pt production
277 case kPyMbAtlasTuneMC09:
278 // Minimum Bias pp-Collisions
281 // select Pythia min. bias model
283 SetMSUB(92,1); // single diffraction AB-->XB
284 SetMSUB(93,1); // single diffraction AB-->AX
285 SetMSUB(94,1); // double diffraction
286 SetMSUB(95,1); // low pt production
291 case kPyMbWithDirectPhoton:
292 // Minimum Bias pp-Collisions with direct photon processes added
295 // select Pythia min. bias model
297 SetMSUB(92,1); // single diffraction AB-->XB
298 SetMSUB(93,1); // single diffraction AB-->AX
299 SetMSUB(94,1); // double diffraction
300 SetMSUB(95,1); // low pt production
313 // Minimum Bias pp-Collisions
316 // select Pythia min. bias model
318 SetMSUB(92,1); // single diffraction AB-->XB
319 SetMSUB(93,1); // single diffraction AB-->AX
320 SetMSUB(94,1); // double diffraction
321 SetMSUB(95,1); // low pt production
324 // Les Houches Working Group 05 Minimum Bias pp-Collisions: hep-ph/0604120
325 // -> Pythia 6.3 or above is needed
328 SetMSUB(92,1); // single diffraction AB-->XB
329 SetMSUB(93,1); // single diffraction AB-->AX
330 SetMSUB(94,1); // double diffraction
331 SetMSUB(95,1); // low pt production
333 SetMSTP(51,AliStructFuncType::PDFsetIndex(kCTEQ6ll)); // CTEQ6ll pdf
337 SetMSTP(81,1); // Multiple Interactions ON
338 SetMSTP(82,4); // Double Gaussian Model
341 SetPARP(82,2.3); // [GeV] PT_min at Ref. energy
342 SetPARP(83,0.5); // Core density in proton matter distribution (def.value)
343 SetPARP(84,0.5); // Core radius
344 SetPARP(85,0.9); // Regulates gluon prod. mechanism
345 SetPARP(90,0.2); // 2*epsilon (exponent in power law)
349 // Minimum Bias pp-Collisions
352 // select Pythia min. bias model
354 SetMSUB(95,1); // low pt production
361 SetMSTP(91,1);// Width (1=gaussian) primordial kT dist. inside hadrons
362 SetPARP(91,1.); // <kT^2> = PARP(91,1.)^2
363 SetPARP(93,5.); // Upper cut-off
365 SetPMAS(4,1,1.2); // Charm quark mass
366 SetPMAS(5,1,4.78); // Beauty quark mass
367 SetPARP(71,4.); // Defaut value
376 // Pythia Tune A (CDF)
378 SetPARP(67,2.5); // Regulates Initial State Radiation (value from best fit to D0 dijet analysis)
379 SetMSTP(82,4); // Double Gaussian Model
380 SetPARP(82,2.0); // [GeV] PT_min at Ref. energy
381 SetPARP(84,0.4); // Core radius
382 SetPARP(85,0.90) ; // Regulates gluon prod. mechanism
383 SetPARP(86,0.95); // Regulates gluon prod. mechanism
384 SetPARP(89,1800.); // [GeV] Ref. energy
385 SetPARP(90,0.25); // 2*epsilon (exponent in power law)
390 case kPyCharmPbPbMNR:
392 case kPyDPlusPbPbMNR:
393 case kPyDPlusStrangePbPbMNR:
394 // Tuning of Pythia parameters aimed to get a resonable agreement
395 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
396 // c-cbar single inclusive and double differential distributions.
397 // This parameter settings are meant to work with Pb-Pb collisions
398 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
399 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
400 // has to be set to 2.1GeV. Example in ConfigCharmPPR.C.
412 case kPyDPlusStrangepPbMNR:
413 // Tuning of Pythia parameters aimed to get a resonable agreement
414 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
415 // c-cbar single inclusive and double differential distributions.
416 // This parameter settings are meant to work with p-Pb collisions
417 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
418 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
419 // has to be set to 2.1GeV. Example in ConfigCharmPPR.C.
432 case kPyDPlusStrangeppMNR:
433 case kPyLambdacppMNR:
434 // Tuning of Pythia parameters aimed to get a resonable agreement
435 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
436 // c-cbar single inclusive and double differential distributions.
437 // This parameter settings are meant to work with pp collisions
438 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
439 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
440 // has to be set to 2.1GeV. Example in ConfigCharmPPR.C.
450 case kPyCharmppMNRwmi:
451 // Tuning of Pythia parameters aimed to get a resonable agreement
452 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
453 // c-cbar single inclusive and double differential distributions.
454 // This parameter settings are meant to work with pp collisions
455 // and with kCTEQ5L PDFs.
456 // Added multiple interactions according to ATLAS tune settings.
457 // To get a "reasonable" agreement with MNR results, events have to be
458 // generated with the minimum ptHard (AliGenPythia::SetPtHard)
460 // To get a "perfect" agreement with MNR results, events have to be
461 // generated in four ptHard bins with the following relative
477 case kPyBeautyPbPbMNR:
478 // Tuning of Pythia parameters aimed to get a resonable agreement
479 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
480 // b-bbar single inclusive and double differential distributions.
481 // This parameter settings are meant to work with Pb-Pb collisions
482 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
483 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
484 // has to be set to 2.75GeV. Example in ConfigBeautyPPR.C.
496 case kPyBeautypPbMNR:
497 // Tuning of Pythia parameters aimed to get a resonable agreement
498 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
499 // b-bbar single inclusive and double differential distributions.
500 // This parameter settings are meant to work with p-Pb collisions
501 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
502 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
503 // has to be set to 2.75GeV. Example in ConfigBeautyPPR.C.
516 // Tuning of Pythia parameters aimed to get a resonable agreement
517 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
518 // b-bbar single inclusive and double differential distributions.
519 // This parameter settings are meant to work with pp collisions
520 // (AliGenPythia::SetNuclei) and with kCTEQ4L PDFs.
521 // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
522 // has to be set to 2.75GeV. Example in ConfigBeautyPPR.C.
537 case kPyBeautyppMNRwmi:
538 // Tuning of Pythia parameters aimed to get a resonable agreement
539 // between with the NLO calculation by Mangano, Nason, Ridolfi for the
540 // b-bbar single inclusive and double differential distributions.
541 // This parameter settings are meant to work with pp collisions
542 // and with kCTEQ5L PDFs.
543 // Added multiple interactions according to ATLAS tune settings.
544 // To get a "reasonable" agreement with MNR results, events have to be
545 // generated with the minimum ptHard (AliGenPythia::SetPtHard)
547 // To get a "perfect" agreement with MNR results, events have to be
548 // generated in four ptHard bins with the following relative
571 //Inclusive production of W+/-
577 // //f fbar -> gamma W+
584 // Initial/final parton shower on (Pythia default)
585 // With parton showers on we are generating "W inclusive process"
586 SetMSTP(61,1); //Initial QCD & QED showers on
587 SetMSTP(71,1); //Final QCD & QED showers on
593 //Inclusive production of Z
598 // // f fbar -> g Z/gamma
600 // // f fbar -> gamma Z/gamma
602 // // f g -> f Z/gamma
604 // // f gamma -> f Z/gamma
607 //only Z included, not gamma
610 // Initial/final parton shower on (Pythia default)
611 // With parton showers on we are generating "Z inclusive process"
612 SetMSTP(61,1); //Initial QCD & QED showers on
613 SetMSTP(71,1); //Final QCD & QED showers on
616 case kPyMBRSingleDiffraction:
617 case kPyMBRDoubleDiffraction:
618 case kPyMBRCentralDiffraction:
623 // For the case of jet production the following parameter setting
624 // limits the transverse momentum of secondary scatterings, due
625 // to multiple parton interactions, to be less than that of the
626 // primary interaction (see POWHEG Dijet paper arXiv:1012.3380
627 // [hep-ph] sec. 4.1 and also the PYTHIA Manual).
630 // maximum number of errors before pythia aborts (def=10)
632 // number of warnings printed on the shell
638 // number of warnings printed on the shell
649 if (GetMSTP(192) > 1 || GetMSTP(193) > 1) {
650 AliWarning(Form("Structure function for tune %5d set to %5s\n",
651 itune, AliStructFuncType::PDFsetName(strucfunc).Data()));
653 SetMSTP(51, AliStructFuncType::PDFsetIndex(strucfunc));
657 SetMSTP(41,1); // all resonance decays switched on
658 if (process == kPyJetsPWHG || process == kPyCharmPWHG || process == kPyBeautyPWHG) {
659 Initialize("USER","","",0.);
661 Initialize("CMS",fProjectile,fTarget,fEcms);
666 Int_t AliPythia::CheckedLuComp(Int_t kf)
668 // Check Lund particle code (for debugging)
670 printf("\n Lucomp kf,kc %d %d",kf,kc);
674 void AliPythia::SetNuclei(Int_t a1, Int_t a2, Int_t pdf)
676 // Treat protons as inside nuclei with mass numbers a1 and a2
677 // The MSTP array in the PYPARS common block is used to enable and
678 // select the nuclear structure functions.
679 // MSTP(52) : (D=1) choice of proton and nuclear structure-function library
680 // =1: internal PYTHIA acording to MSTP(51)
681 // =2: PDFLIB proton s.f., with MSTP(51) = 1000xNGROUP+NSET
682 // If the following mass number both not equal zero, nuclear corrections of the stf are used.
683 // MSTP(192) : Mass number of nucleus side 1
684 // MSTP(193) : Mass number of nucleus side 2
685 // MSTP(194) : Nuclear structure function: 0: EKS98 8:EPS08 9:EPS09LO 19:EPS09NLO
693 AliPythia* AliPythia::Instance()
695 // Set random number generator
699 fgAliPythia = new AliPythia();
704 void AliPythia::PrintParticles()
706 // Print list of particl properties
708 char* name = new char[16];
709 for (Int_t kf=0; kf<1000000; kf++) {
710 for (Int_t c = 1; c > -2; c-=2) {
711 Int_t kc = Pycomp(c*kf);
713 Float_t mass = GetPMAS(kc,1);
714 Float_t width = GetPMAS(kc,2);
715 Float_t tau = GetPMAS(kc,4);
721 printf("\n mass, width, tau: %6d %s %10.3f %10.3e %10.3e",
722 c*kf, name, mass, width, tau);
726 printf("\n Number of particles %d \n \n", np);
729 void AliPythia::ResetDecayTable()
731 // Set default values for pythia decay switches
733 for (i = 1; i < 501; i++) SetMDCY(i,1,fDefMDCY[i]);
734 for (i = 1; i < 2001; i++) SetMDME(i,1,fDefMDME[i]);
737 void AliPythia::SetDecayTable()
739 // Set default values for pythia decay switches
742 for (i = 1; i < 501; i++) fDefMDCY[i] = GetMDCY(i,1);
743 for (i = 1; i < 2001; i++) fDefMDME[i] = GetMDME(i,1);
746 void AliPythia::Pyclus(Int_t& njet)
748 // Call Pythia clustering algorithm
753 void AliPythia::Pycell(Int_t& njet)
755 // Call Pythia jet reconstruction algorithm
760 void AliPythia::Pyshow(Int_t ip1, Int_t ip2, Double_t qmax)
762 // Call Pythia jet reconstruction algorithm
764 pyshow(ip1, ip2, qmax);
767 void AliPythia::Pyrobo(Int_t imi, Int_t ima, Double_t the, Double_t phi, Double_t bex, Double_t bey, Double_t bez)
769 pyrobo(imi, ima, the, phi, bex, bey, bez);
772 void AliPythia::Pytune(Int_t itune)
776 C ITUNE NAME (detailed descriptions below)
777 C 0 Default : No settings changed => linked Pythia version's defaults.
778 C ====== Old UE, Q2-ordered showers ==========================================
779 C 100 A : Rick Field's CDF Tune A
780 C 101 AW : Rick Field's CDF Tune AW
781 C 102 BW : Rick Field's CDF Tune BW
782 C 103 DW : Rick Field's CDF Tune DW
783 C 104 DWT : Rick Field's CDF Tune DW with slower UE energy scaling
784 C 105 QW : Rick Field's CDF Tune QW (NB: needs CTEQ6.1M pdfs externally)
785 C 106 ATLAS-DC2: Arthur Moraes' (old) ATLAS tune (ATLAS DC2 / Rome)
786 C 107 ACR : Tune A modified with annealing CR
787 C 108 D6 : Rick Field's CDF Tune D6 (NB: needs CTEQ6L pdfs externally)
788 C 109 D6T : Rick Field's CDF Tune D6T (NB: needs CTEQ6L pdfs externally)
789 C ====== Intermediate Models =================================================
790 C 200 IM 1 : Intermediate model: new UE, Q2-ordered showers, annealing CR
791 C 201 APT : Tune A modified to use pT-ordered final-state showers
792 C ====== New UE, interleaved pT-ordered showers, annealing CR ================
793 C 300 S0 : Sandhoff-Skands Tune 0
794 C 301 S1 : Sandhoff-Skands Tune 1
795 C 302 S2 : Sandhoff-Skands Tune 2
796 C 303 S0A : S0 with "Tune A" UE energy scaling
797 C 304 NOCR : New UE "best try" without colour reconnections
798 C 305 Old : New UE, original (primitive) colour reconnections
799 C 306 ATLAS-CSC: Arthur Moraes' (new) ATLAS tune (needs CTEQ6L externally)
800 C ======= The Uppsala models =================================================
801 C ( NB! must be run with special modified Pythia 6.215 version )
802 C ( available from http://www.isv.uu.se/thep/MC/scigal/ )
803 C 400 GAL 0 : Generalized area-law model. Old parameters
804 C 401 SCI 0 : Soft-Colour-Interaction model. Old parameters
805 C 402 GAL 1 : Generalized area-law model. Tevatron MB retuned (Skands)
810 void AliPythia::Py2ent(Int_t idx, Int_t pdg1, Int_t pdg2, Double_t p){
811 // Inset 2-parton system at line idx
812 py2ent(idx, pdg1, pdg2, p);
816 void AliPythia::InitQuenching(Float_t cMin, Float_t cMax, Float_t k, Int_t iECMethod, Float_t zmax, Int_t ngmax)
819 // (1) The quenching model using quenching weights according to C. Salgado and U. Wiedemann
820 // (2) The nuclear geometry using the Glauber Model
823 fGlauber = AliFastGlauber::Instance();
825 fGlauber->SetCentralityClass(cMin, cMax);
827 fQuenchingWeights = new AliQuenchingWeights();
828 fQuenchingWeights->InitMult();
829 fQuenchingWeights->SetK(k);
830 fQuenchingWeights->SetECMethod(AliQuenchingWeights::kECMethod(iECMethod));
837 void AliPythia::Quench()
841 // Simple Jet Quenching routine:
842 // =============================
843 // The jet formed by all final state partons radiated by the parton created
844 // in the hard collisions is quenched by a factor (1-z) using light cone variables in
845 // the initial parton reference frame:
846 // (E + p_z)new = (1-z) (E + p_z)old
851 // The lost momentum is first balanced by one gluon with virtuality > 0.
852 // Subsequently the gluon splits to yield two gluons with E = p.
856 static Float_t eMean = 0.;
857 static Int_t icall = 0;
862 Int_t klast[4] = {-1, -1, -1, -1};
864 Int_t numpart = fPyjets->N;
865 Double_t px = 0., py = 0., pz = 0., e = 0., m = 0., p = 0., pt = 0., theta = 0., phi = 0.;
866 Double_t pxq[4], pyq[4], pzq[4], eq[4], yq[4], mq[4], pq[4], phiq[4], thetaq[4], ptq[4];
868 Double_t wjtKick[4] = {0., 0., 0., 0.};
874 // Sore information about Primary partons
877 // 0, 1 partons from hard scattering
878 // 2, 3 partons from initial state radiation
880 for (Int_t i = 2; i <= 7; i++) {
882 // Skip gluons that participate in hard scattering
883 if (i == 4 || i == 5) continue;
884 // Gluons from hard Scattering
885 if (i == 6 || i == 7) {
887 pxq[j] = fPyjets->P[0][i];
888 pyq[j] = fPyjets->P[1][i];
889 pzq[j] = fPyjets->P[2][i];
890 eq[j] = fPyjets->P[3][i];
891 mq[j] = fPyjets->P[4][i];
893 // Gluons from initial state radiation
895 // Obtain 4-momentum vector from difference between original parton and parton after gluon
896 // radiation. Energy is calculated independently because initial state radition does not
897 // conserve strictly momentum and energy for each partonic system independently.
899 // Not very clean. Should be improved !
903 pxq[j] = fPyjets->P[0][i] - fPyjets->P[0][i+2];
904 pyq[j] = fPyjets->P[1][i] - fPyjets->P[1][i+2];
905 pzq[j] = fPyjets->P[2][i] - fPyjets->P[2][i+2];
906 mq[j] = fPyjets->P[4][i];
907 eq[j] = TMath::Sqrt(pxq[j] * pxq[j] + pyq[j] * pyq[j] + pzq[j] * pzq[j] + mq[j] * mq[j]);
910 // Calculate some kinematic variables
912 yq[j] = 0.5 * TMath::Log((eq[j] + pzq[j] + 1.e-14) / (eq[j] - pzq[j] + 1.e-14));
913 pq[j] = TMath::Sqrt(pxq[j] * pxq[j] + pyq[j] * pyq[j] + pzq[j] * pzq[j]);
914 phiq[j] = TMath::Pi()+TMath::ATan2(-pyq[j], -pxq[j]);
915 ptq[j] = TMath::Sqrt(pxq[j] * pxq[j] + pyq[j] * pyq[j]);
916 thetaq[j] = TMath::ATan2(ptq[j], pzq[j]);
917 qPdg[j] = fPyjets->K[1][i];
923 fGlauber->GetI0I1ForPythiaAndXY(4, phiq, int0, int1, fXJet, fYJet, 15.);
925 for (Int_t j = 0; j < 4; j++) {
927 // Quench only central jets and with E > 10.
931 Int_t itype = (qPdg[j] == 21) ? 2 : 1;
932 Double_t eloss = fQuenchingWeights->GetELossRandomKFast(itype, int0[j], int1[j], eq[j]);
934 if (TMath::Abs(yq[j]) > 2.5 || eq[j] < 10.) {
937 if (eq[j] > 40. && TMath::Abs(yq[j]) < 0.5) {
943 Double_t l = fQuenchingWeights->CalcLk(int0[j], int1[j]);
944 wjtKick[j] = TMath::Sqrt(l * fQuenchingWeights->CalcQk(int0[j], int1[j]));
946 // Fractional energy loss
947 fZQuench[j] = eloss / eq[j];
949 // Avoid complete loss
951 if (fZQuench[j] > fZmax) fZQuench[j] = fZmax;
953 // Some debug printing
956 // 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",
957 // j, itype, eq[j], phiq[j], l, eloss, wjtKick[j], eMean / Float_t(icall+1), yq[j]);
959 // fZQuench[j] = 0.8;
960 // while (fZQuench[j] >= 0.95) fZQuench[j] = gRandom->Exp(0.2);
963 quenched[j] = (fZQuench[j] > 0.01);
968 Double_t pNew[1000][4];
975 for (Int_t isys = 0; isys < 4; isys++) {
976 // Skip to next system if not quenched.
977 if (!quenched[isys]) continue;
979 nGluon[isys] = 1 + Int_t(fZQuench[isys] / (1. - fZQuench[isys]));
980 if (nGluon[isys] > fNGmax) nGluon[isys] = fNGmax;
981 zquench[isys] = 1. - TMath::Power(1. - fZQuench[isys], 1./Double_t(nGluon[isys]));
982 wjtKick[isys] = wjtKick[isys] / TMath::Sqrt(Double_t(nGluon[isys]));
988 Double_t pg[4] = {0., 0., 0., 0.};
991 // Loop on radiation events
993 for (Int_t iglu = 0; iglu < nGluon[isys]; iglu++) {
996 for (Int_t k = 0; k < 4; k++)
1002 // Loop over partons
1003 for (Int_t i = 0; i < numpart; i++)
1005 imo = fPyjets->K[2][i];
1006 kst = fPyjets->K[0][i];
1007 pdg = fPyjets->K[1][i];
1011 // Quarks and gluons only
1012 if (pdg != 21 && TMath::Abs(pdg) > 6) continue;
1013 // Particles from hard scattering only
1015 if (imo > 8 && imo < 1000) imo = fPyjets->K[2][imo - 1];
1016 Int_t imom = imo % 1000;
1017 if ((isys == 0 || isys == 1) && ((imom != (isys + 7)))) continue;
1018 if ((isys == 2 || isys == 3) && ((imom != (isys + 1)))) continue;
1021 // Skip comment lines
1022 if (kst != 1 && kst != 2) continue;
1025 px = fPyjets->P[0][i];
1026 py = fPyjets->P[1][i];
1027 pz = fPyjets->P[2][i];
1028 e = fPyjets->P[3][i];
1029 m = fPyjets->P[4][i];
1030 pt = TMath::Sqrt(px * px + py * py);
1031 p = TMath::Sqrt(px * px + py * py + pz * pz);
1032 phi = TMath::Pi() + TMath::ATan2(-py, -px);
1033 theta = TMath::ATan2(pt, pz);
1036 // Save 4-momentum sum for balancing
1047 // Fractional energy loss
1048 Double_t z = zquench[index];
1051 // Don't fully quench radiated gluons
1054 // This small factor makes sure that the gluons are not too close in phase space to avoid recombination
1059 // printf("z: %d %f\n", imo, z);
1066 // Transform into frame in which initial parton is along z-axis
1068 TVector3 v(px, py, pz);
1069 v.RotateZ(-phiq[index]); v.RotateY(-thetaq[index]);
1070 Double_t pxs = v.X(); Double_t pys = v.Y(); Double_t pl = v.Z();
1072 Double_t jt = TMath::Sqrt(pxs * pxs + pys * pys);
1073 Double_t mt2 = jt * jt + m * m;
1076 // Kinematic limit on z
1078 if (m > 0.) zmax = 1. - m / TMath::Sqrt(m * m + jt * jt);
1080 // Change light-cone kinematics rel. to initial parton
1082 Double_t eppzOld = e + pl;
1083 Double_t empzOld = e - pl;
1085 Double_t eppzNew = (1. - z) * eppzOld;
1086 Double_t empzNew = empzOld - mt2 * z / eppzOld;
1087 Double_t eNew = 0.5 * (eppzNew + empzNew);
1088 Double_t plNew = 0.5 * (eppzNew - empzNew);
1092 // if mt very small (or sometimes even < 0 for numerical reasons) set it to 0
1093 Double_t mt2New = eppzNew * empzNew;
1094 if (mt2New < 1.e-8) mt2New = 0.;
1096 if (m * m > mt2New) {
1098 // This should not happen
1100 Fatal("Quench()", "This should never happen %e %e %e!", m, eppzNew, empzNew);
1103 jtNew = TMath::Sqrt(mt2New - m * m);
1106 // If pT is to small (probably a leading massive particle) we scale only the energy
1107 // This can cause negative masses of the radiated gluon
1108 // Let's hope for the best ...
1110 eNew = TMath::Sqrt(plNew * plNew + mt2);
1114 // Calculate new px, py
1120 pxNew = jtNew / jt * pxs;
1121 pyNew = jtNew / jt * pys;
1123 // Double_t dpx = pxs - pxNew;
1124 // Double_t dpy = pys - pyNew;
1125 // Double_t dpz = pl - plNew;
1126 // Double_t de = e - eNew;
1127 // Double_t dmass2 = de * de - dpx * dpx - dpy * dpy - dpz * dpz;
1128 // printf("New mass (1) %e %e %e %e %e %e %e \n", dmass2, jt, jtNew, pl, plNew, e, eNew);
1129 // printf("New mass (2) %e %e \n", pxNew, pyNew);
1133 TVector3 w(pxNew, pyNew, plNew);
1134 w.RotateY(thetaq[index]); w.RotateZ(phiq[index]);
1135 pxNew = w.X(); pyNew = w.Y(); plNew = w.Z();
1137 p1[index][0] += pxNew;
1138 p1[index][1] += pyNew;
1139 p1[index][2] += plNew;
1140 p1[index][3] += eNew;
1142 // Updated 4-momentum vectors
1144 pNew[icount][0] = pxNew;
1145 pNew[icount][1] = pyNew;
1146 pNew[icount][2] = plNew;
1147 pNew[icount][3] = eNew;
1152 // Check if there was phase-space for quenching
1155 if (icount == 0) quenched[isys] = kFALSE;
1156 if (!quenched[isys]) break;
1158 for (Int_t j = 0; j < 4; j++)
1160 p2[isys][j] = p0[isys][j] - p1[isys][j];
1162 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];
1163 if (p2[isys][4] > 0.) {
1164 p2[isys][4] = TMath::Sqrt(p2[isys][4]);
1167 printf("Warning negative mass squared in system %d %f ! \n", isys, zquench[isys]);
1168 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]);
1169 if (p2[isys][4] < -0.01) {
1170 printf("Negative mass squared !\n");
1171 // Here we have to put the gluon back to mass shell
1172 // This will lead to a small energy imbalance
1174 p2[isys][3] = TMath::Sqrt(p2[isys][0] * p2[isys][0] + p2[isys][1] * p2[isys][1] + p2[isys][2] * p2[isys][2]);
1183 printf("zHeavy lowered to %f\n", zHeavy);
1184 if (zHeavy < 0.01) {
1185 printf("No success ! \n");
1187 quenched[isys] = kFALSE;
1191 } // iteration on z (while)
1193 // Update event record
1194 for (Int_t k = 0; k < icount; k++) {
1195 // 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] );
1196 fPyjets->P[0][kNew[k]] = pNew[k][0];
1197 fPyjets->P[1][kNew[k]] = pNew[k][1];
1198 fPyjets->P[2][kNew[k]] = pNew[k][2];
1199 fPyjets->P[3][kNew[k]] = pNew[k][3];
1206 if (!quenched[isys]) continue;
1208 // Last parton from shower i
1209 Int_t in = klast[isys];
1211 // Continue if no parton in shower i selected
1212 if (in == -1) continue;
1214 // If this is the second initial parton and it is behind the first move pointer by previous ish
1215 if (isys == 1 && klast[1] > klast[0]) in += ish;
1220 // How many additional gluons will be generated
1222 if (p2[isys][4] > 0.05) ish = 2;
1224 // Position of gluons
1226 if (iglu == 0) igMin = iGlu;
1229 (fPyjets->N) += ish;
1232 fPyjets->P[0][iGlu] = p2[isys][0];
1233 fPyjets->P[1][iGlu] = p2[isys][1];
1234 fPyjets->P[2][iGlu] = p2[isys][2];
1235 fPyjets->P[3][iGlu] = p2[isys][3];
1236 fPyjets->P[4][iGlu] = p2[isys][4];
1238 fPyjets->K[0][iGlu] = 1;
1239 if (iglu == nGluon[isys] - 1) fPyjets->K[0][iGlu] = 1;
1240 fPyjets->K[1][iGlu] = 21;
1241 fPyjets->K[2][iGlu] = fPyjets->K[2][in] + 1000;
1242 fPyjets->K[3][iGlu] = -1;
1243 fPyjets->K[4][iGlu] = -1;
1245 pg[0] += p2[isys][0];
1246 pg[1] += p2[isys][1];
1247 pg[2] += p2[isys][2];
1248 pg[3] += p2[isys][3];
1251 // Split gluon in rest frame.
1253 Double_t bx = p2[isys][0] / p2[isys][3];
1254 Double_t by = p2[isys][1] / p2[isys][3];
1255 Double_t bz = p2[isys][2] / p2[isys][3];
1256 Double_t pst = p2[isys][4] / 2.;
1258 // Isotropic decay ????
1259 Double_t cost = 2. * gRandom->Rndm() - 1.;
1260 Double_t sint = TMath::Sqrt((1.-cost)*(1.+cost));
1261 Double_t phis = 2. * TMath::Pi() * gRandom->Rndm();
1263 Double_t pz1 = pst * cost;
1264 Double_t pz2 = -pst * cost;
1265 Double_t pt1 = pst * sint;
1266 Double_t pt2 = -pst * sint;
1267 Double_t px1 = pt1 * TMath::Cos(phis);
1268 Double_t py1 = pt1 * TMath::Sin(phis);
1269 Double_t px2 = pt2 * TMath::Cos(phis);
1270 Double_t py2 = pt2 * TMath::Sin(phis);
1272 fPyjets->P[0][iGlu] = px1;
1273 fPyjets->P[1][iGlu] = py1;
1274 fPyjets->P[2][iGlu] = pz1;
1275 fPyjets->P[3][iGlu] = pst;
1276 fPyjets->P[4][iGlu] = 0.;
1278 fPyjets->K[0][iGlu] = 1 ;
1279 fPyjets->K[1][iGlu] = 21;
1280 fPyjets->K[2][iGlu] = fPyjets->K[2][in] + 1000;
1281 fPyjets->K[3][iGlu] = -1;
1282 fPyjets->K[4][iGlu] = -1;
1284 fPyjets->P[0][iGlu+1] = px2;
1285 fPyjets->P[1][iGlu+1] = py2;
1286 fPyjets->P[2][iGlu+1] = pz2;
1287 fPyjets->P[3][iGlu+1] = pst;
1288 fPyjets->P[4][iGlu+1] = 0.;
1290 fPyjets->K[0][iGlu+1] = 1;
1291 if (iglu == nGluon[isys] - 1) fPyjets->K[0][iGlu+1] = 1;
1292 fPyjets->K[1][iGlu+1] = 21;
1293 fPyjets->K[2][iGlu+1] = fPyjets->K[2][in] + 1000;
1294 fPyjets->K[3][iGlu+1] = -1;
1295 fPyjets->K[4][iGlu+1] = -1;
1301 Pyrobo(iGlu + 1, iGlu + 2, 0., 0., bx, by, bz);
1304 for (Int_t ig = iGlu; ig < iGlu+ish; ig++) {
1305 Double_t px, py, pz;
1306 px = fPyjets->P[0][ig];
1307 py = fPyjets->P[1][ig];
1308 pz = fPyjets->P[2][ig];
1309 TVector3 v(px, py, pz);
1310 v.RotateZ(-phiq[isys]);
1311 v.RotateY(-thetaq[isys]);
1312 Double_t pxs = v.X(); Double_t pys = v.Y(); Double_t pzs = v.Z();
1313 Double_t r = AliPythiaRndm::GetPythiaRandom()->Rndm();
1314 Double_t jtKick = 0.3 * TMath::Sqrt(-TMath::Log(r));
1315 if (ish == 2) jtKick = wjtKick[i] * TMath::Sqrt(-TMath::Log(r)) / TMath::Sqrt(2.);
1316 Double_t phiKick = 2. * TMath::Pi() * AliPythiaRndm::GetPythiaRandom()->Rndm();
1317 pxs += jtKick * TMath::Cos(phiKick);
1318 pys += jtKick * TMath::Sin(phiKick);
1319 TVector3 w(pxs, pys, pzs);
1320 w.RotateY(thetaq[isys]);
1321 w.RotateZ(phiq[isys]);
1322 fPyjets->P[0][ig] = w.X();
1323 fPyjets->P[1][ig] = w.Y();
1324 fPyjets->P[2][ig] = w.Z();
1325 fPyjets->P[2][ig] = w.Mag();
1331 // Check energy conservation
1335 Double_t es = 14000.;
1337 for (Int_t i = 0; i < numpart; i++)
1339 kst = fPyjets->K[0][i];
1340 if (kst != 1 && kst != 2) continue;
1341 pxs += fPyjets->P[0][i];
1342 pys += fPyjets->P[1][i];
1343 pzs += fPyjets->P[2][i];
1344 es -= fPyjets->P[3][i];
1346 if (TMath::Abs(pxs) > 1.e-2 ||
1347 TMath::Abs(pys) > 1.e-2 ||
1348 TMath::Abs(pzs) > 1.e-1) {
1349 printf("%e %e %e %e\n", pxs, pys, pzs, es);
1350 // Fatal("Quench()", "4-Momentum non-conservation");
1353 } // end quenching loop (systems)
1355 for (Int_t i = 0; i < numpart; i++)
1357 imo = fPyjets->K[2][i];
1359 fPyjets->K[2][i] = fPyjets->K[2][i] % 1000;
1366 void AliPythia::Pyquen(Double_t a, Int_t ibf, Double_t b)
1368 // Igor Lokthine's quenching routine
1369 // http://lokhtin.web.cern.ch/lokhtin/pyquen/pyquen.txt
1374 void AliPythia::SetPyquenParameters(Double_t t0, Double_t tau0, Int_t nf, Int_t iengl, Int_t iangl)
1376 // Set the parameters for the PYQUEN package.
1377 // See comments in PyquenCommon.h
1383 PYQPAR.iengl = iengl;
1384 PYQPAR.iangl = iangl;
1388 void AliPythia::Pyevnw()
1390 // New multiple interaction scenario
1394 void AliPythia::Pyshowq(Int_t ip1, Int_t ip2, Double_t qmax)
1396 // Call medium-modified Pythia jet reconstruction algorithm
1398 pyshowq(ip1, ip2, qmax);
1400 void AliPythia::Qpygin0()
1402 // New multiple interaction scenario
1406 void AliPythia::GetQuenchingParameters(Double_t& xp, Double_t& yp, Double_t z[4])
1408 // Return event specific quenching parameters
1411 for (Int_t i = 0; i < 4; i++) z[i] = fZQuench[i];
1415 void AliPythia::ConfigHeavyFlavor()
1418 // Default configuration for Heavy Flavor production
1420 // All QCD processes
1426 // No multiple interactions
1431 // Initial/final parton shower on (Pythia default)
1435 // 2nd order alpha_s
1443 void AliPythia::AtlasTuning()
1446 // Configuration for the ATLAS tuning
1447 if (fItune > -1) return;
1448 printf("ATLAS TUNE \n");
1450 SetMSTP(51, AliStructFuncType::PDFsetIndex(kCTEQ5L)); // CTEQ5L pdf
1451 SetMSTP(81,1); // Multiple Interactions ON
1452 SetMSTP(82,4); // Double Gaussian Model
1453 SetPARP(81,1.9); // Min. pt for multiple interactions (default in 6.2-14)
1454 SetPARP(82,1.8); // [GeV] PT_min at Ref. energy
1455 SetPARP(89,1000.); // [GeV] Ref. energy
1456 SetPARP(90,0.16); // 2*epsilon (exponent in power law)
1457 SetPARP(83,0.5); // Core density in proton matter distribution (def.value)
1458 SetPARP(84,0.5); // Core radius
1459 SetPARP(85,0.33); // Regulates gluon prod. mechanism
1460 SetPARP(86,0.66); // Regulates gluon prod. mechanism
1461 SetPARP(67,1); // Regulates Initial State Radiation
1464 void AliPythia::AtlasTuningMC09()
1467 // Configuration for the ATLAS tuning
1468 if (fItune > -1) return;
1469 printf("ATLAS New TUNE MC09\n");
1470 SetMSTP(81,21); // treatment for MI, ISR, FSR and beam remnants: MI on, new model
1471 SetMSTP(82, 4); // Double Gaussian Model
1472 SetMSTP(52, 2); // External PDF
1473 SetMSTP(51, 20650); // MRST LO*
1476 SetMSTP(70, 0); // (was 2: def manual 1, def code 0) virtuality scale for ISR
1477 SetMSTP(72, 1); // (was 0: def 1) maximum scale for FSR
1478 SetMSTP(88, 1); // (was 0: def 1) strategy for qq junction to di-quark or baryon in beam remnant
1479 SetMSTP(90, 0); // (was 1: def 0) strategy of compensate the primordial kT
1481 SetPARP(78, 0.3); // the amount of color reconnection in the final state
1482 SetPARP(80, 0.1); // probability of color partons kicked out from beam remnant
1483 SetPARP(82, 2.3); // [GeV] PT_min at Ref. energy
1484 SetPARP(83, 0.8); // Core density in proton matter distribution (def.value)
1485 SetPARP(84, 0.7); // Core radius
1486 SetPARP(90, 0.25); // 2*epsilon (exponent in power law)
1487 SetPARJ(81, 0.29); // (was 0.14: def 0.29) Labmda value in running alpha_s for parton showers
1490 SetPARJ(41, 0.3); // a and b parameters of the symmm. Lund FF
1492 SetPARJ(46, 0.75); // mod. of the Lund FF for heavy end-point quarks
1493 SetPARP(89,1800.); // [GeV] Ref. energy
1496 AliPythia& AliPythia::operator=(const AliPythia& rhs)
1498 // Assignment operator
1503 void AliPythia::Copy(TObject&) const
1508 Fatal("Copy","Not implemented!\n");
1511 void AliPythia::DalitzDecays()
1515 // Replace all omega dalitz decays with the correct matrix element decays
1517 Int_t nt = fPyjets->N;
1518 for (Int_t i = 0; i < nt; i++) {
1519 if (fPyjets->K[1][i] != 223) continue;
1520 Int_t fd = fPyjets->K[3][i] - 1;
1521 Int_t ld = fPyjets->K[4][i] - 1;
1522 if (fd < 0) continue;
1523 if ((ld - fd) != 2) continue;
1524 if ((fPyjets->K[1][fd] != 111) ||
1525 ((TMath::Abs(fPyjets->K[1][fd+1]) != 11) && (TMath::Abs(fPyjets->K[1][fd+1]) != 13)))
1527 TLorentzVector omega(fPyjets->P[0][i], fPyjets->P[1][i], fPyjets->P[2][i], fPyjets->P[3][i]);
1528 Int_t pdg = TMath::Abs(fPyjets->K[1][fd+1]);
1529 fOmegaDalitz.Decay(pdg, &omega);
1530 for (Int_t j = 0; j < 3; j++) {
1531 for (Int_t k = 0; k < 4; k++) {
1532 TLorentzVector vec = (fOmegaDalitz.Products())[2-j];
1533 fPyjets->P[k][fd+j] = vec[k];