Option kPyCharmPbMNR added. Produce charm pairs in agreement with MNR

NLO calculations (Nicola Carrer).

diff --git a/EVGEN/AliGenPythia.cxx b/EVGEN/AliGenPythia.cxx
index b00d9f56c20876676b9c4124950f661c25dc6d6b..1b331d198d87d501a96661e507c2a47d38f884f0 100644 (file)
--- a/EVGEN/AliGenPythia.cxx
+++ b/EVGEN/AliGenPythia.cxx
@@ -15,6 +15,9 @@
 
 /*
 $Log$
+Revision 1.49  2002/02/08 16:50:50  morsch
+Add name and title in constructor.
+
 Revision 1.48  2001/12/20 11:44:28  morsch
 Add kinematic bias for direct gamma production.
 
@@ -237,13 +240,8 @@ void AliGenPythia::Init()
     switch (fProcess) 
     {
     case kPyCharm:
-       fParentSelect[0] =  411;
-       fParentSelect[1] =  421;
-       fParentSelect[2] =  431;
-       fParentSelect[3] = 4122;        
-       fFlavorSelect    = 4;
-       break;
     case kPyCharmUnforced:
+    case kPyCharmPbMNR:
        fParentSelect[0] =   411;
        fParentSelect[1] =   421;
        fParentSelect[2] =   431;

diff --git a/EVGEN/AliPythia.cxx b/EVGEN/AliPythia.cxx
index 7e06141751aff8ede01575bd5d5f98c7aa70cfb2..7b2db5122e202d6be680a8ad1c8ca2903515f185 100644 (file)
--- a/EVGEN/AliPythia.cxx
+++ b/EVGEN/AliPythia.cxx
@@ -15,6 +15,9 @@
 
 /*
 $Log$
+Revision 1.19  2002/02/20 08:52:20  morsch
+Correct documentation of SetNuclei method.
+
 Revision 1.18  2002/02/07 10:43:06  morsch
 Tuned pp-min.bias settings (M.Monteno, R.Ugoccioni and N.Carrer)
 
@@ -190,6 +193,43 @@ void AliPythia::ProcInit(Process_t process, Float_t energy, StrucFunc_t strucfun
     case kPyDirectGamma:
        SetMSEL(10);
        break;
+    case kPyCharmPbMNR:
+      // Tuning of Pythia parameters aimed to get a resonable agreement
+      // between with the NLO calculation by Mangano, Nason, Ridolfi for the
+      // c-cbar single inclusive and double differential distributions.
+      // This parameter settings are meant to work with Pb-Pb collisions
+      // (AliGenPythia::SetNuclei) and with kCTEQ_4L PDFs.
+      // To get a good agreement the minimum ptHard (AliGenPythia::SetPtHard)
+      // has to be set to 2.1GeV. Example in ConfigCharmPPR.C.
+
+      // All QCD processes
+      SetMSEL(1);
+
+      // No multiple interactions
+      SetMSTP(81,0);
+      SetPARP(81,0.0);
+      SetPARP(82,0.0);
+
+      // Initial/final parton shower on (Pythia default)
+      SetMSTP(61,1);
+      SetMSTP(71,1);
+
+      // 2nd order alpha_s
+      SetMSTP(2,2);
+
+      // QCD scales
+      SetMSTP(32,2);
+      SetPARP(34,1.0);
+
+      // Intrinsic <kT^2>
+      SetMSTP(91,1);
+      SetPARP(91,1.304);
+      SetPARP(93,6.52);
+
+      // Set c-quark mass
+      SetPMAS(4,1,1.2);
+
+      break;
     }
 //
 //  Initialize PYTHIA

diff --git a/EVGEN/AliPythia.h b/EVGEN/AliPythia.h
index 8108a61bf471224ba8e626a0e9c26aedb3fb8901..309d607d1b7a2daa4f0c2381419e75ce71a02f33 100644 (file)
--- a/EVGEN/AliPythia.h
+++ b/EVGEN/AliPythia.h
@@ -9,7 +9,7 @@
 #include <AliRndm.h>
 
 typedef enum
-{kPyCharm, kPyBeauty, kPyCharmUnforced, kPyBeautyUnforced, kPyJpsi, kPyJpsiChi, kPyMb, kPyJets, kPyDirectGamma}
+{kPyCharm, kPyBeauty, kPyCharmUnforced, kPyBeautyUnforced, kPyJpsi, kPyJpsiChi, kPyMb, kPyJets, kPyDirectGamma, kPyCharmPbMNR}
 Process_t;
 
 typedef enum