]> git.uio.no Git - u/mrichter/AliRoot.git/blobdiff - EVGEN/AliGenMUONCocktailpp.cxx
Afterburner to generate light nuclei
[u/mrichter/AliRoot.git] / EVGEN / AliGenMUONCocktailpp.cxx
index c9b8376cb3faaf224a31f73fc11549f4abe108cc..6cd7ce84cd7239751a3efbbc491194d60a47afb8 100644 (file)
 // i.e. gener->SetCMSEnergy(AliGenMUONCocktailpp::kCMS07TeV) in Config.C 
 // - resonances now added to the cocktail via AddReso2Generator 
 // - cleaning 
-// B.Vulpescu & P.Crochet         
+// B.Vulpescu & P.Crochet
+//-----------------------         
+// 10/2011: 
+// - added the cocktail for p-Pb & Pb-p @ 8.8 TeV with 4 centrality bins and
+// for Pb-Pb @ 2.76 TeV with 11 centrality bins. Bins should be defined also
+// in the Config.C with one AliGenMUONCocktailpp per bin. These generators
+// included in a AliGenCocktail together with an event generator (e.g. Hijing)
+// providing the underlying event and collision centrality. The bin number n
+// passed via AliGenMUONCocktailpp::SetCentralityBin(n).
+// See details in my presentation at the PWG3-Muon meeting (05.10.2011):
+// https://indico.cern.ch/conferenceDisplay.py?confId=157367
+// - simplifications and bug fix in CreateCocktail() 
+// S. Grigoryan
+//-----------------------
+// 06/2012:
+// - added the cocktail for p-Pb & Pb-p @ 2.76, 4.4 & 5.03 TeV with 4 centrality 
+// bins, using the EPS09-LO shadowing computed for 5.03 TeV. Energies are set by
+// AliGenMUONCocktailpp::SetCMSEnergy(int CMSEnergyCode), CMSEnergy codes are
+// defined in AliGenMUONCocktailpp.h.
+// - added functions to scale x-section of JPsi, Charmonia, Bottomonia, CCbar & BBbar
+// in Config.C to manage the statistics. Example of usage (in a cocktail with Hijing):
+/*
+  AliGenCocktail *cocktail = new AliGenCocktail();
+  cocktail->AddGenerator(hijing,"hijing",1);
+  TFormula *form[nb];  // nb - number of centrality bins with impact params bBins[i]
+  AliGenMUONCocktailpp *gen[nb];
+  for (Int_t i=0; i<nb; i++) {
+    form[i] = new TFormula(Form("f%d",i),"[0]+(x-[1])/([2]-[1])");
+    form[i]->SetParameters(i+1, bBins[i], bBins[i+1]);
+    gen[i] = MuonCocktail();
+    gen[i]->SetCentralityBin(i+1);
+    gen[i]->ScaleJPsi(100.);
+    gen[i]->CreateCocktail();
+    cocktail->AddGenerator(gen[i], Form("g%d",i), 101+i, form[i]);
+  }
+AliGenMUONCocktailpp* MuonCocktail() {
+  AliGenMUONCocktailpp *mc = new AliGenMUONCocktailpp();
+  ....................................
+  return mc;
+}
+*/
+// - a bug fixed in the function Generate()
+// S. Grigoryan
  
 #include <TObjArray.h>
 #include <TParticle.h>
@@ -77,6 +119,12 @@ AliGenMUONCocktailpp::AliGenMUONCocktailpp()
      fMuonOriginCut(-999.),
      fNSucceded(0),
      fNGenerated(0),
+     fCentralityBin(0),
+     fScaleJPsi(1),
+     fScaleCharmonia(1),
+     fScaleBottomonia(1),
+     fScaleCCbar(1),
+     fScaleBBbar(1),
 
      fJpsiPol(0), 
      fChic1Pol(0), 
@@ -114,24 +162,29 @@ AliGenMUONCocktailpp::AliGenMUONCocktailpp()
 {
 // Constructor
 
-// x-sections for pp @ 7 TeV: charmonia from hep-ph/0311048 Tab.9, page 19,
-// bottomnium as for 10 TeV
+// x-sections for pp @ 7 TeV: 
+// -charmonia: 4pi integral of fit function for inclusive J/psi dsigma/dy LHC data 
+// gives 60 mub; so sigma_prompt = 54 mub, while Ref = R.Vogt_arXiv:1003.3497 (Table 2)
+// gives 35 mub. Below we use sigma_direct from the Ref scaled by the factor 54/35.
+// -bottomonia: 4pi integral of fit function for inclusive Upsilon1S dsigma/dy LHC data
+// gives 0.56 mub, sigmas for 2S & 3S obtained using LHCb data for ratios 2S/1S & 3S/1S
+// -ccbar & bbbar: NLO pQCD computations - http://www-alice.gsi.de/ana/MNR/results.html
     fCMSEnergyTeVArray[0] =   7.00;
-    fSigmaReactionArray[0] =  0.0695;
-    fSigmaJPsiArray[0] =      21.8e-6;
-    fSigmaChic1Array[0] =     21.1e-6;
-    fSigmaChic2Array[0] =     34.9e-6;
-    fSigmaPsiPArray[0] =      4.93e-6;
-    fSigmaUpsilonArray[0] =   0.463e-6;
-    fSigmaUpsilonPArray[0] =  0.154e-6;
-    fSigmaUpsilonPPArray[0] = 0.0886e-6;
+    fSigmaReactionArray[0] =  0.070;
+    fSigmaJPsiArray[0] =      33.6e-6;
+    fSigmaChic1Array[0] =     32.6e-6;
+    fSigmaChic2Array[0] =     53.8e-6;
+    fSigmaPsiPArray[0] =       7.6e-6;
+    fSigmaUpsilonArray[0] =   0.56e-6;
+    fSigmaUpsilonPArray[0] =  0.18e-6;
+    fSigmaUpsilonPPArray[0] = 0.08e-6;
     fSigmaCCbarArray[0] =     6.91e-3;
     fSigmaBBbarArray[0] =     0.232e-3;
     
 //x-sections for pp @ 10 TeV: charmonia and bottomonia from 14 TeV numbers
-// scaled down according to ccbar and bbar cross-sections
+// scaled down according to ccbar and bbbar cross-sections
     fCMSEnergyTeVArray[1] =   10.00;
-    fSigmaReactionArray[1] =  0.0695;
+    fSigmaReactionArray[1] =  0.070;
     fSigmaJPsiArray[1] =      26.06e-6;
     fSigmaChic1Array[1] =     25.18e-6;
     fSigmaChic2Array[1] =     41.58e-6;
@@ -141,9 +194,9 @@ AliGenMUONCocktailpp::AliGenMUONCocktailpp()
     fSigmaUpsilonPPArray[1] = 0.122e-6;
     fSigmaCCbarArray[1] =     8.9e-3;
     fSigmaBBbarArray[1] =     0.33e-3;
-    
+
 //x-sections for pp @ 14 TeV: charmonia from hep-ph/0311048 Tab.9, page 19,
-// bottomonium from hep-ph/0311048 Tab.9, page 19 taken inton account that 
+// bottomonium from hep-ph/0311048 Tab.9, page 19 taken into account that 
 // feed-down from chib is included
     fCMSEnergyTeVArray[2] =   14.00;
     fSigmaReactionArray[2] =  0.070;
@@ -155,7 +208,130 @@ AliGenMUONCocktailpp::AliGenMUONCocktailpp()
     fSigmaUpsilonPArray[2] =  0.502e-6;
     fSigmaUpsilonPPArray[2] = 0.228e-6;
     fSigmaCCbarArray[2] =     11.2e-3;
-    fSigmaBBbarArray[2] =     0.51e-3;
+    fSigmaBBbarArray[2] =     0.445e-3;
+
+// x-sections for Min. Bias p-Pb & Pb-p @ 2.76 TeV: charmonia and bottomonia 
+// from 7 TeV numbers scaled according to pQCD ccbar and bbbar x-sections
+// and with Glauber scaling
+    fCMSEnergyTeVArray[3] =   2.00;           // for 2.76 TeV
+    fSigmaReactionArray[3] =  2.10;
+    fSigmaJPsiArray[3] =      3.54e-3;        // 208*0.507*33.6e-6
+    fSigmaChic1Array[3] =     3.44e-3;
+    fSigmaChic2Array[3] =     5.66e-3;
+    fSigmaPsiPArray[3] =      0.80e-3;
+    fSigmaUpsilonArray[3] =   0.045e-3;       // 208*0.384*0.56e-6
+    fSigmaUpsilonPArray[3] =  0.014e-3;
+    fSigmaUpsilonPPArray[3] = 0.006e-3;
+    fSigmaCCbarArray[3] =     0.73;           // 208*3.50e-3
+    fSigmaBBbarArray[3] =     0.019;          // 208*0.089e-3
+
+    fCMSEnergyTeVArray[4] =  -fCMSEnergyTeVArray[3];
+    fSigmaReactionArray[4] =  fSigmaReactionArray[3];
+    fSigmaJPsiArray[4] =      fSigmaJPsiArray[3];
+    fSigmaChic1Array[4] =     fSigmaChic1Array[3];
+    fSigmaChic2Array[4] =     fSigmaChic2Array[3];
+    fSigmaPsiPArray[4] =      fSigmaPsiPArray[3];
+    fSigmaUpsilonArray[4] =   fSigmaUpsilonArray[3];
+    fSigmaUpsilonPArray[4] =  fSigmaUpsilonPArray[3];
+    fSigmaUpsilonPPArray[4] = fSigmaUpsilonPPArray[3];
+    fSigmaCCbarArray[4] =     fSigmaCCbarArray[3];
+    fSigmaBBbarArray[4] =     fSigmaBBbarArray[3];
+
+// x-sections for Min. Bias p-Pb & Pb-p @ 4.4 TeV: charmonia and bottomonia 
+// from 7 TeV numbers scaled according to pQCD ccbar and bbbar x-sections
+// and with Glauber scaling
+    fCMSEnergyTeVArray[5] =   4.00;           // for 4.4 TeV
+    fSigmaReactionArray[5] =  2.10;
+    fSigmaJPsiArray[5] =      5.00e-3;        // 208*0.715*33.6e-6
+    fSigmaChic1Array[5] =     4.86e-3;
+    fSigmaChic2Array[5] =     7.99e-3;
+    fSigmaPsiPArray[5] =      1.12e-3;
+    fSigmaUpsilonArray[5] =   0.074e-3;       // 208*0.629*0.56e-6
+    fSigmaUpsilonPArray[5] =  0.023e-3;
+    fSigmaUpsilonPPArray[5] = 0.010e-3;
+    fSigmaCCbarArray[5] =     1.03;           // 208*4.94e-3
+    fSigmaBBbarArray[5] =     0.030;          // 208*0.146e-3
+
+    fCMSEnergyTeVArray[6] =  -fCMSEnergyTeVArray[5];
+    fSigmaReactionArray[6] =  fSigmaReactionArray[5];
+    fSigmaJPsiArray[6] =      fSigmaJPsiArray[5];
+    fSigmaChic1Array[6] =     fSigmaChic1Array[5];
+    fSigmaChic2Array[6] =     fSigmaChic2Array[5];
+    fSigmaPsiPArray[6] =      fSigmaPsiPArray[5];
+    fSigmaUpsilonArray[6] =   fSigmaUpsilonArray[5];
+    fSigmaUpsilonPArray[6] =  fSigmaUpsilonPArray[5];
+    fSigmaUpsilonPPArray[6] = fSigmaUpsilonPPArray[5];
+    fSigmaCCbarArray[6] =     fSigmaCCbarArray[5];
+    fSigmaBBbarArray[6] =     fSigmaBBbarArray[5];
+
+// x-sections for Min. Bias p-Pb & Pb-p @ 5.03 TeV: charmonia and bottomonia 
+// from 7 TeV numbers scaled according to pQCD ccbar and bbbar x-sections
+// and with Glauber scaling
+    fCMSEnergyTeVArray[7] =   5.00;           // for 5.03 TeV
+    fSigmaReactionArray[7] =  2.10;
+    fSigmaJPsiArray[7] =      5.50e-3;        // 208*0.787*33.6e-6
+    fSigmaChic1Array[7] =     5.35e-3;
+    fSigmaChic2Array[7] =     8.79e-3;
+    fSigmaPsiPArray[7] =      1.23e-3;
+    fSigmaUpsilonArray[7] =   0.083e-3;       // 208*0.716*0.56e-6
+    fSigmaUpsilonPArray[7] =  0.026e-3;
+    fSigmaUpsilonPPArray[7] = 0.011e-3;
+    fSigmaCCbarArray[7] =     1.13;           // 208*5.44e-3
+    fSigmaBBbarArray[7] =     0.035;          // 208*0.166e-3
+
+    fCMSEnergyTeVArray[8] =  -fCMSEnergyTeVArray[7];
+    fSigmaReactionArray[8] =  fSigmaReactionArray[7];
+    fSigmaJPsiArray[8] =      fSigmaJPsiArray[7];
+    fSigmaChic1Array[8] =     fSigmaChic1Array[7];
+    fSigmaChic2Array[8] =     fSigmaChic2Array[7];
+    fSigmaPsiPArray[8] =      fSigmaPsiPArray[7];
+    fSigmaUpsilonArray[8] =   fSigmaUpsilonArray[7];
+    fSigmaUpsilonPArray[8] =  fSigmaUpsilonPArray[7];
+    fSigmaUpsilonPPArray[8] = fSigmaUpsilonPPArray[7];
+    fSigmaCCbarArray[8] =     fSigmaCCbarArray[7];
+    fSigmaBBbarArray[8] =     fSigmaBBbarArray[7];
+
+// x-sections for Min. Bias p-Pb & Pb-p @ 8.8 TeV: charmonia and bottomonia 
+// from 7 TeV numbers scaled according to pQCD ccbar and bbbar x-sections
+// and with Glauber scaling
+    fCMSEnergyTeVArray[9] =   9.00;           // for 8.8 TeV
+    fSigmaReactionArray[9] =  2.10;
+    fSigmaJPsiArray[9] =      8.19e-3;        // 208*1.172*33.6e-6
+    fSigmaChic1Array[9] =     7.95e-3;
+    fSigmaChic2Array[9] =     13.1e-3;
+    fSigmaPsiPArray[9] =      1.85e-3;
+    fSigmaUpsilonArray[9] =   0.146e-3;       // 208*1.25*0.56e-6
+    fSigmaUpsilonPArray[9] =  0.047e-3;
+    fSigmaUpsilonPPArray[9] = 0.021e-3;
+    fSigmaCCbarArray[9] =     1.68;           // 208*8.1e-3
+    fSigmaBBbarArray[9] =     0.061;          // 208*0.29e-3
+
+    fCMSEnergyTeVArray[10] =  -fCMSEnergyTeVArray[9];
+    fSigmaReactionArray[10] =  fSigmaReactionArray[9];
+    fSigmaJPsiArray[10] =      fSigmaJPsiArray[9];
+    fSigmaChic1Array[10] =     fSigmaChic1Array[9];
+    fSigmaChic2Array[10] =     fSigmaChic2Array[9];
+    fSigmaPsiPArray[10] =      fSigmaPsiPArray[9];
+    fSigmaUpsilonArray[10] =   fSigmaUpsilonArray[9];
+    fSigmaUpsilonPArray[10] =  fSigmaUpsilonPArray[9];
+    fSigmaUpsilonPPArray[10] = fSigmaUpsilonPPArray[9];
+    fSigmaCCbarArray[10] =     fSigmaCCbarArray[9];
+    fSigmaBBbarArray[10] =     fSigmaBBbarArray[9];
+
+// x-sections for Min. Bias Pb-Pb @ 2.76 TeV: charmonia and bottomonia 
+// from 7 TeV numbers scaled according to pQCD ccbar and bbbar x-sections
+// and with Glauber scaling
+    fCMSEnergyTeVArray[11] =   3.00;           // for 2.76 TeV
+    fSigmaReactionArray[11] =  7.65;
+    fSigmaJPsiArray[11] =      0.737;          // 208*208*0.507*33.6e-6
+    fSigmaChic1Array[11] =     0.715;
+    fSigmaChic2Array[11] =     1.179;
+    fSigmaPsiPArray[11] =      0.166;
+    fSigmaUpsilonArray[11] =   0.0093;         // 208*208*0.384*0.56e-6
+    fSigmaUpsilonPArray[11] =  0.0030;
+    fSigmaUpsilonPPArray[11] = 0.0013;
+    fSigmaCCbarArray[11] =     151.;           // 208*208*3.50e-3
+    fSigmaBBbarArray[11] =     3.8;            // 208*208*0.089e-3
     
 }
 
@@ -219,6 +395,10 @@ void AliGenMUONCocktailpp::CreateCocktail()
 // create and add resonances and open HF to the coctail
     Int_t cmsEnergy = Int_t(fCMSEnergyTeV);
 
+    // For temporary use of p-Pb & Pb-p shadowing at 5.03 TeV for lower energies  
+    if (cmsEnergy == 2 || cmsEnergy == 4) cmsEnergy = 5;
+    if (cmsEnergy == -2 || cmsEnergy == -4) cmsEnergy = -5;
+
 // These limits are only used for renormalization of quarkonia cross section
 // Pythia events are generated in 4pi  
     Double_t ptMin  = fPtMin;
@@ -229,8 +409,7 @@ void AliGenMUONCocktailpp::CreateCocktail()
     Double_t phiMax = fPhiMax*180./TMath::Pi();
     AliInfo(Form("Ranges pT:%4.1f : %4.1f GeV/c, y:%4.2f : %4.2f, Phi:%5.1f : %5.1f degres",ptMin,ptMax,yMin,yMax,phiMin,phiMax));
     
-// Cross sections in barns (from PPR Vol. II p: 552) pp - 14 TeV and 
-// corrected from feed down of higher resonances 
+// Cross sections in barns
 
     Double_t sigmajpsi      = fSigmaJPsi;  
     Double_t sigmachic1     = fSigmaChic1;  
@@ -253,6 +432,18 @@ void AliGenMUONCocktailpp::CreateCocktail()
     if(TMath::Abs(fUpsPPol) > 1.e-30) {sigmaupsilonP  = fSigmaUpsilonP*0.0193;}
     if(TMath::Abs(fUpsPPPol) > 1.e-30) {sigmaupsilonPP = fSigmaUpsilonPP*0.0218;}
 
+// Cross sections scaled to manage the statistics
+
+    sigmajpsi      *= fScaleJPsi*fScaleCharmonia;  
+    sigmachic1     *= fScaleCharmonia;  
+    sigmachic2     *= fScaleCharmonia;  
+    sigmapsiP      *= fScaleCharmonia;  
+    sigmaupsilon   *= fScaleBottomonia;  
+    sigmaupsilonP  *= fScaleBottomonia;  
+    sigmaupsilonPP *= fScaleBottomonia;  
+    sigmaccbar     *= fScaleCCbar;  
+    sigmabbbar     *= fScaleBBbar;  
+
     AliInfo(Form("the parametrised resonances uses the decay mode %d",fDecayModeResonance));
 
 // Create and add resonances to the generator
@@ -280,55 +471,98 @@ void AliGenMUONCocktailpp::CreateCocktail()
     snprintf(nameUpsP,10, "UpsP");
     snprintf(nameUpsPP,10, "UpsPP");
 
-    if(cmsEnergy == 10){
-       genjpsi = new AliGenParam(1, AliGenMUONlib::kJpsi, "CDF pp 10", "Jpsi");
-       genchic1 = new AliGenParam(1, AliGenMUONlib::kChic1, "CDF pp 10", "Chic1");
-       genchic2 = new AliGenParam(1, AliGenMUONlib::kChic2, "CDF pp 10", "Chic2");
-       genpsiP = new AliGenParam(1, AliGenMUONlib::kPsiP, "CDF pp 10", "PsiP");
-       genupsilon = new AliGenParam(1, AliGenMUONlib::kUpsilon, "CDF pp 10", "Upsilon");
-
-       genupsilonP = new AliGenParam(1, AliGenMUONlib::kUpsilonP, "CDF pp 10", "UpsilonP");
-       genupsilonPP = new AliGenParam(1, AliGenMUONlib::kUpsilonPP, "CDF pp 10", "UpsilonPP");
-    } else if (cmsEnergy == 7){
-       genjpsi = new AliGenParam(1, AliGenMUONlib::kJpsi, "CDF pp 7", "Jpsi");
-       genchic1 = new AliGenParam(1, AliGenMUONlib::kChic1, "CDF pp 7", "Chic1");
-       genchic2 = new AliGenParam(1, AliGenMUONlib::kChic2, "CDF pp 7", "Chic2");
-       genpsiP = new AliGenParam(1, AliGenMUONlib::kPsiP, "CDF pp 7", "PsiP");
-
-       genupsilon = new AliGenParam(1, AliGenMUONlib::kUpsilon, "CDF pp 7", "Upsilon");
-       genupsilonP = new AliGenParam(1, AliGenMUONlib::kUpsilonP, "CDF pp 7", "UpsilonP");
-       genupsilonPP = new AliGenParam(1, AliGenMUONlib::kUpsilonPP, "CDF pp 7", "UpsilonPP");
-    } else if (cmsEnergy == 14){
-       genjpsi = new AliGenParam(1, AliGenMUONlib::kJpsi, "CDF pp ", "Jpsi");
-       genchic1 = new AliGenParam(1, AliGenMUONlib::kChic1, "CDF pp ", "Chic1");
-       genchic2 = new AliGenParam(1, AliGenMUONlib::kChic2, "CDF pp ", "Chic2");
-       genpsiP = new AliGenParam(1, AliGenMUONlib::kPsiP, "CDF pp", "PsiP");
-
-       genupsilon = new AliGenParam(1, AliGenMUONlib::kUpsilon, "CDF pp", "Upsilon");
-       genupsilonP = new AliGenParam(1, AliGenMUONlib::kUpsilonP, "CDF pp", "UpsilonP");
-
-       genupsilonPP = new AliGenParam(1, AliGenMUONlib::kUpsilonPP, "CDF pp", "UpsilonPP");    
+    Char_t tname[40] = "";
+    if(cmsEnergy == 10)        {snprintf(tname, 40, "CDF pp 10");
+    } else if (cmsEnergy == 14){snprintf(tname, 40, "CDF pp");
+    } else if (cmsEnergy == 7) {snprintf(tname, 40, "pp 7");
+      //    } else if (cmsEnergy == 2) {snprintf(tname, 40, "pp 2.76");
+    } else if (cmsEnergy == 5) {snprintf(tname, 40, "pPb 5.03");
+      if (fCentralityBin > 0) snprintf(tname, 40, "pPb 5.03c%d",fCentralityBin); 
+    } else if (cmsEnergy == -5){snprintf(tname, 40, "Pbp 5.03");
+      if (fCentralityBin > 0) snprintf(tname, 40, "Pbp 5.03c%d",fCentralityBin); 
+    } else if (cmsEnergy == 9) {snprintf(tname, 40, "pPb 8.8");
+      if (fCentralityBin > 0) snprintf(tname, 40, "pPb 8.8c%d",fCentralityBin); 
+    } else if (cmsEnergy == -9){snprintf(tname, 40, "Pbp 8.8");
+      if (fCentralityBin > 0) snprintf(tname, 40, "Pbp 8.8c%d",fCentralityBin); 
+    } else if (cmsEnergy == 3) {snprintf(tname, 40, "PbPb 2.76");
+      if (fCentralityBin > 0) snprintf(tname, 40, "PbPb 2.76c%d",fCentralityBin); 
     } else {
-       AliError("Initialisation failed");
+       AliError("Initialisation failed, wrong cmsEnergy");
        return;
     }
-    
+    genjpsi = new AliGenParam(1, AliGenMUONlib::kJpsi, tname, "Jpsi");
+    genchic1 = new AliGenParam(1, AliGenMUONlib::kChic1, tname, "Chic1");
+    genchic2 = new AliGenParam(1, AliGenMUONlib::kChic2,  tname, "Chic2");
+    genpsiP   = new AliGenParam(1, AliGenMUONlib::kPsiP,   tname, "PsiP");
+    genupsilon = new AliGenParam(1, AliGenMUONlib::kUpsilon, tname, "Upsilon");
+    genupsilonP = new AliGenParam(1, AliGenMUONlib::kUpsilonP, tname, "UpsilonP");
+    genupsilonPP = new AliGenParam(1, AliGenMUONlib::kUpsilonPP, tname, "UpsilonPP");
+
+// Hard process yield per pA or AA collision for i-th centrality bin is R*r[i]*shad[i]
+// where R is the ratio of hard and geometrical x-sections, r[i] is the ratio of these
+// x-section fractions for given centrality and shad[i] is the shadowing factor (in 4pi).
+// The latter is assumed to be the same for HF-hadrons & quarkonia of the same flavour.
+    Int_t i = 0;
+    Double_t chard[20] = {0};     // charm & beauty shadowing factors are different
+    Double_t bhard[20] = {0};
+    chard[0] = 1;                 // 1st element for pp and min. bias (MB) collisions
+    bhard[0] = 1;
+
+// 4 centrality bins for p-Pb & Pb-p at 5.03 TeV: 0-20-40-60-100 % 
+    if (cmsEnergy == 5 || cmsEnergy == -5) {
+      const Int_t n5 = 5;         // 1st element for MB collisions
+      Double_t r5[n5] = {1, 1.936, 1.473, 0.914, 0.333};        // ratio of hard-over-geo fractions
+      Double_t cshad5[n5] = {0.806, 0.742, 0.796, 0.870, 0.955};// EPS09-LO shadowing factors
+      Double_t bshad5[n5] = {0.917, 0.889, 0.913, 0.944, 0.981};
+      for(i=0; i<n5; i++) {
+         chard[i] = cshad5[i]*r5[i];   
+         bhard[i] = bshad5[i]*r5[i];
+      }
+    }
+
+// 4 centrality bins for p-Pb & Pb-p at 8.8 TeV: 0-20-40-60-100 % 
+    if (cmsEnergy == 9 || cmsEnergy == -9) {
+      const Int_t n9 = 5;         // 1st element for MB collisions
+      Double_t r9[n9] = {1, 1.936, 1.473, 0.914, 0.333};        // ratio of hard-over-geo fractions
+      Double_t cshad9[n9] = {0.785, 0.715, 0.775, 0.856, 0.951};// EKS98 shadowing factors
+      Double_t bshad9[n9] = {0.889, 0.853, 0.884, 0.926, 0.975};
+      for(i=0; i<n9; i++) {
+         chard[i] = cshad9[i]*r9[i];   
+         bhard[i] = bshad9[i]*r9[i];
+      }
+    }
+
+// 11 centrality bins for Pb-Pb at 2.76 TeV: 0-5-10-20-30-40-50-60-70-80-90-100 % 
+    if (cmsEnergy == 3) {
+      const Int_t n3 = 12;        // 1st element for MB collisions
+      Double_t r3[n3] = {1, 4.661, 3.647, 2.551, 1.544, 0.887, 0.474,
+                           0.235, 0.106, 0.044, 0.017, 0.007};        // ratio of hard-over-geo fractions
+      Double_t cshad3[n3] = {0.662, 0.622, 0.631, 0.650, 0.681, 0.718, 
+                            0.760, 0.805, 0.849, 0.888, 0.918, 0.944};// EKS98 shadowing factors
+      Double_t bshad3[n3] = {0.874, 0.856, 0.861, 0.869, 0.883, 0.898, 
+                            0.915, 0.932, 0.948, 0.962, 0.972, 0.981};
+      for(i=0; i<n3; i++) {
+         chard[i] = cshad3[i]*r3[i];   
+         bhard[i] = bshad3[i]*r3[i];
+      }
+    }
+
+    AddReso2Generator(nameJpsi,genjpsi,chard[fCentralityBin]*sigmajpsi,fJpsiPol);
+    AddReso2Generator(nameChic1,genchic1,chard[fCentralityBin]*sigmachic1,fChic1Pol);
+    AddReso2Generator(nameChic2,genchic2,chard[fCentralityBin]*sigmachic2,fChic2Pol);
+    AddReso2Generator(namePsiP,genpsiP,chard[fCentralityBin]*sigmapsiP,fPsiPPol);
 
-    AddReso2Generator(nameJpsi,genjpsi,sigmajpsi,fJpsiPol);
-    AddReso2Generator(nameChic1,genchic2,sigmachic1,fChic2Pol);
-    AddReso2Generator(nameChic2,genpsiP,sigmapsiP,fPsiPPol);    
-    AddReso2Generator(namePsiP,genchic1,sigmachic1,fChic1Pol);    
-    AddReso2Generator(nameUps,genupsilon,sigmaupsilon,fUpsPol);    
-    AddReso2Generator(nameUpsP,genupsilonP,sigmaupsilonP,fUpsPPol);    
-    AddReso2Generator(nameUpsPP,genupsilonPP,sigmaupsilonPP,fUpsPPPol);    
+    AddReso2Generator(nameUps,genupsilon,bhard[fCentralityBin]*sigmaupsilon,fUpsPol);
+    AddReso2Generator(nameUpsP,genupsilonP,bhard[fCentralityBin]*sigmaupsilonP,fUpsPPol);
+    AddReso2Generator(nameUpsPP,genupsilonPP,bhard[fCentralityBin]*sigmaupsilonPP,fUpsPPPol);
 
 //------------------------------------------------------------------
 // Generator of charm
     AliGenCorrHF *gencharm = new AliGenCorrHF(1, 4, cmsEnergy);
     gencharm->SetMomentumRange(0,9999);
     gencharm->SetForceDecay(kAll);
-    Double_t ratioccbar = sigmaccbar/fSigmaReaction;
-    if (!gMC) gencharm->SetDecayer(fDecayer);  
+    Double_t ratioccbar = chard[fCentralityBin]*sigmaccbar/fSigmaReaction;
+    if (!TVirtualMC::GetMC()) gencharm->SetDecayer(fDecayer);  
     gencharm->Init();
     if (!fSigmaSilent) {
       AliInfo(Form("c-cbar prod. cross-section in pp %5.3g b",sigmaccbar));
@@ -340,8 +574,8 @@ void AliGenMUONCocktailpp::CreateCocktail()
     AliGenCorrHF *genbeauty = new AliGenCorrHF(1, 5, cmsEnergy);
     genbeauty->SetMomentumRange(0,9999);
     genbeauty->SetForceDecay(kAll);
-    Double_t ratiobbbar = sigmabbbar/fSigmaReaction;
-    if (!gMC) genbeauty->SetDecayer(fDecayer);  
+    Double_t ratiobbbar = bhard[fCentralityBin]*sigmabbbar/fSigmaReaction;
+    if (!TVirtualMC::GetMC()) genbeauty->SetDecayer(fDecayer);  
     genbeauty->Init();
     if (!fSigmaSilent) {
       AliInfo(Form("b-bbar prod. cross-section in pp  %5.3g b",sigmabbbar));
@@ -386,7 +620,7 @@ void AliGenMUONCocktailpp::AddReso2Generator(Char_t* nameReso,
     genReso->SetYRange(-8.,8.);
     genReso->SetPhiRange(0.,360.);
     genReso->SetForceDecay(fDecayModeResonance);
-    if (!gMC) genReso->SetDecayer(fDecayer);  
+    if (!TVirtualMC::GetMC()) genReso->SetDecayer(fDecayer);  
     genReso->Init();  // generation in 4pi
 // Ratios with respect to the reaction cross-section in the 
 // kinematics limit of the MUONCocktail
@@ -441,7 +675,6 @@ void AliGenMUONCocktailpp::Generate()
 // Generate event 
     TIter next(fEntries);
     AliGenCocktailEntry *entry = 0;
-    AliGenCocktailEntry *preventry = 0;
     AliGenerator* gen = 0;
 
     if (fHeader) delete fHeader;
@@ -457,9 +690,10 @@ void AliGenMUONCocktailpp::Generate()
 
     Bool_t primordialTrigger = kFALSE;
     while(!primordialTrigger) {
-       //Reseting stack
+       //Reseting stack (if fMuonMultiplicity > 0 : S. Grigoryan, June 2012)
        AliRunLoader * runloader = AliRunLoader::Instance();
-       if (runloader)
+       //      if (runloader)
+       if (runloader && fMuonMultiplicity > 0)
            if (runloader->Stack())
                runloader->Stack()->Clean();
        // Loop over generators and generate events
@@ -483,7 +717,6 @@ void AliGenMUONCocktailpp::Generate()
                gen->SetNumberParticles(npart);         
                gen->Generate();
                entry->SetLast(partArray->GetEntriesFast());
-               preventry = entry;
            }
        }  
        next.Reset();