Use ATLAS tuning for MB events.
authormorsch <morsch@f7af4fe6-9843-0410-8265-dc069ae4e863>
Thu, 12 Feb 2004 17:58:50 +0000 (17:58 +0000)
committermorsch <morsch@f7af4fe6-9843-0410-8265-dc069ae4e863>
Thu, 12 Feb 2004 17:58:50 +0000 (17:58 +0000)
PYTHIA6/AliPythia.cxx

index 798e76a9e8230c73aece941d82d2dfb1cbdaaa0d..3650a574406dc3f180d308645c8e0508de1f0440 100644 (file)
@@ -136,30 +136,47 @@ void AliPythia::ProcInit(Process_t process, Float_t energy, StrucFunc_t strucfun
 //   
 //      select Pythia min. bias model
        SetMSEL(0);
-       SetMSUB(92,1);      // single diffraction AB-->XB
-       SetMSUB(93,1);      // single diffraction AB-->AX
-       SetMSUB(94,1);      // double diffraction
-       SetMSUB(95,1);      // low pt production
-       SetMSTP(81,1);      // multiple interactions switched on
-       SetMSTP(82,3);      // model with varying impact param. & a single Gaussian
-       SetPARP(82,3.47);   // set value pT_0  for turn-off of the cross section of                  
-                            // multiple interaction at a reference energy = 14000 GeV
-       SetPARP(89,14000.); // reference energy for the above parameter
-       SetPARP(90,0.174);  // set exponent for energy dependence of pT_0
+       SetMSUB(92,1);             // single diffraction AB-->XB
+       SetMSUB(93,1);             // single diffraction AB-->AX
+       SetMSUB(94,1);             // double diffraction
+       SetMSUB(95,1);             // low pt production
+
+//
+// ATLAS Tuning
+//
+        SetMSTP(51, 7);            // CTEQ5L pdf
+       SetMSTP(81,1);             // Multiple Interactions ON
+       SetMSTP(82,4);             // Double Gaussian Model
+
+       SetPARP(82,1.8);           // [GeV]    PT_min at Ref. energy
+       SetPARP(89,1000.);         // [GeV]   Ref. energy
+       SetPARP(90,0.16);          // 2*epsilon (exponent in power law)
+       SetPARP(83,0.5);           // Core density in proton matter distribution (def.value)
+       SetPARP(84,0.5);           // Core radius
+       SetPARP(85,0.33);          // Regulates gluon prod. mechanism
+       SetPARP(86,0.66);          // Regulates gluon prod. mechanism
+       SetPARP(67,1);             // Regulates Initial State Radiation
+       break;
     case kPyMbNonDiffr:
 // Minimum Bias pp-Collisions
 //
 //   
 //      select Pythia min. bias model
        SetMSEL(0);
-       SetMSUB(95,1);      // low pt production
-       SetMSTP(81,1);      // multiple interactions switched on
-       SetMSTP(82,3);      // model with varying impact param. & a single Gaussian
-       SetPARP(82,3.47);   // set value pT_0  for turn-off of the cross section of                  
-                            // multiple interaction at a reference energy = 14000 GeV
-       SetPARP(89,14000.); // reference energy for the above parameter
-       SetPARP(90,0.174);  // set exponent for energy dependence of pT_0
+       SetMSUB(95,1);             // low pt production
+       
+       SetMSTP(51, 7);            // CTEQ5L pdf
+       SetMSTP(81,1);             // Multiple Interactions ON
+       SetMSTP(82,4);             // Double Gaussian Model
+
+       SetPARP(82,1.8);           // [GeV]    PT_min at Ref. energy
+       SetPARP(89,1000.);         // [GeV]   Ref. energy
+       SetPARP(90,0.16);          // 2*epsilon (exponent in power law)
+       SetPARP(83,0.5);           // Core density in proton matter distribution (def.value)
+       SetPARP(84,0.5);           // Core radius
+       SetPARP(85,0.33);          // Regulates gluon prod. mechanism
+       SetPARP(86,0.66);          // Regulates gluon prod. mechanism
+       SetPARP(67,1);             // Regulates Initial State Radiation
        break;
     case kPyJets:
 //
@@ -590,12 +607,11 @@ void  AliPythia::Quench()
        p0[index][0] += px;
        p0[index][1] += py;
        p0[index][2] += pz;
-       p0[index][3] += e;      
+       p0[index][3] += e;
+//
+// Fix z
+//
        
-       //
-       // Fix z
-       //
-
        Float_t z       = 0.2;
        Float_t eppzOld = e + pz;
        Float_t empzOld = e - pz;