Include the bug fixes by Oliver in the TR simulation

diff --git a/TRD/AliTRDsim.cxx b/TRD/AliTRDsim.cxx
index 68097ab5c1063c38a830ed01b6e4c27f3b5f991c..2bb143c1c2c4bd599b6f5649edba9f2bd31b75eb 100644 (file)
--- a/TRD/AliTRDsim.cxx
+++ b/TRD/AliTRDsim.cxx
@@ -15,6 +15,9 @@
 
 /*
 $Log$
 
 /*
 $Log$

+Revision 1.11  2001/11/14 10:50:46  cblume
+Changes in digits IO. Add merging of summable digits
+

 Revision 1.10  2001/05/31 16:53:26  alibrary
 Correction to the destructor
 
 Revision 1.10  2001/05/31 16:53:26  alibrary
 Correction to the destructor
 


@@ -363,14 +366,11 @@ Double_t AliTRDsim::Sigma(Double_t energykeV)
   // Calculates the absorbtion crosssection for a one-foil-one-gap-radiator
   //
 
   // Calculates the absorbtion crosssection for a one-foil-one-gap-radiator
   //
 

-  // Gas at 0 C
-  const Double_t kTemp0 = 273.16;
-

   // keV -> MeV
   Double_t energyMeV = energykeV * 0.001;
   if (energyMeV >= 0.001) {
   // keV -> MeV
   Double_t energyMeV = energykeV * 0.001;
   if (energyMeV >= 0.001) {

-    return(GetMuPo(energyMeV) * fFoilDens * fFoilThick + 
-           GetMuCO(energyMeV) * fGapDens  * fGapThick  * fTemp/kTemp0);
+    return(GetMuPo(energyMeV) * fFoilDens * fFoilThick +
+           GetMuAi(energyMeV) * fGapDens  * fGapThick  * GetTemp());

   }
   else {
     return 1e6;
   }
   else {
     return 1e6;


@@ -698,6 +698,50 @@ Double_t AliTRDsim::GetMuHe(Double_t energyMeV)
 
 }
 
 
 }
 

+//_____________________________________________________________________________
+Double_t AliTRDsim::GetMuAi(Double_t energyMeV)
+{
+  //
+  // Returns the photon absorbtion cross section for air
+  // Implemented by Oliver Busch
+  //
+
+  const Int_t kN = 38;
+
+  Double_t mu[kN] = { 0.35854E+04, 0.11841E+04, 0.52458E+03,
+                      0.16143E+03, 0.14250E+03, 0.15722E+03,
+                      0.77538E+02, 0.40099E+02, 0.23313E+02,
+                      0.98816E+01, 0.51000E+01, 0.16079E+01,
+                      0.77536E+00, 0.35282E+00, 0.24790E+00,
+                      0.20750E+00, 0.18703E+00, 0.16589E+00,
+                      0.15375E+00, 0.13530E+00, 0.12311E+00,
+                      0.10654E+00, 0.95297E-01, 0.86939E-01,
+                      0.80390E-01, 0.70596E-01, 0.63452E-01,
+                      0.56754E-01, 0.51644E-01, 0.44382E-01,
+                      0.35733E-01, 0.30721E-01, 0.27450E-01,
+                      0.25171E-01, 0.22205E-01, 0.20399E-01,
+                      0.18053E-01, 0.18057E-01 };
+
+
+
+  Double_t en[kN] = { 0.10000E-02, 0.15000E-02, 0.20000E-02,
+                      0.30000E-02, 0.32029E-02, 0.32029E-02,
+                      0.40000E-02, 0.50000E-02, 0.60000E-02,
+                      0.80000E-02, 0.10000E-01, 0.15000E-01,
+                      0.20000E-01, 0.30000E-01, 0.40000E-01,
+                      0.50000E-01, 0.60000E-01, 0.80000E-01,
+                      0.10000E+00, 0.15000E+00, 0.20000E+00,
+                      0.30000E+00, 0.40000E+00, 0.50000E+00,
+                      0.60000E+00, 0.80000E+00, 0.10000E+01,
+                      0.12500E+01, 0.15000E+01, 0.20000E+01,
+                      0.30000E+01, 0.40000E+01, 0.50000E+01,
+                      0.60000E+01, 0.80000E+01, 0.10000E+02,
+                      0.15000E+02, 0.20000E+02 };
+
+  return Interpolate(energyMeV,en,mu,kN);
+
+}
+

 //_____________________________________________________________________________
 Double_t AliTRDsim::Interpolate(Double_t energyMeV
                               , Double_t *en, Double_t *mu, Int_t n)
 //_____________________________________________________________________________
 Double_t AliTRDsim::Interpolate(Double_t energyMeV
                               , Double_t *en, Double_t *mu, Int_t n)

diff --git a/TRD/AliTRDsim.h b/TRD/AliTRDsim.h
index 71971e179c8237048b0268f9f972c99d806ce8f4..4a5ae6a55818214b0a0d3e710433cf45173d55f3 100644 (file)
--- a/TRD/AliTRDsim.h
+++ b/TRD/AliTRDsim.h
@@ -71,16 +71,17 @@ class AliTRDsim : public TObject {
   virtual Double_t      GetMuN2(Double_t energyMeV);
   virtual Double_t      GetMuO2(Double_t energyMeV);
   virtual Double_t      GetMuHe(Double_t energyMeV);
   virtual Double_t      GetMuN2(Double_t energyMeV);
   virtual Double_t      GetMuO2(Double_t energyMeV);
   virtual Double_t      GetMuHe(Double_t energyMeV);

-
-          Int_t         GetNFoils() const       { return fNFoils;    };
-          Float_t       GetFoilThick() const    { return fFoilThick; };
-          Float_t       GetGapThick() const     { return fGapThick;  };
-          Float_t       GetFoilDens() const     { return fFoilDens;  };
-          Float_t       GetGapDens() const      { return fGapDens;   };
-          Double_t      GetFoilOmega() const    { return fFoilOmega; };
-          Double_t      GetGapOmega() const     { return fGapOmega;  };
-          Float_t       GetTemp() const         { return fTemp;      };
-          TH1D         *GetSpectrum() const     { return fSpectrum;  };
+  virtual Double_t      GetMuAi(Double_t energyMeV);
+
+          Int_t         GetNFoils() const       { return fNFoils;        };
+          Float_t       GetFoilThick() const    { return fFoilThick;     };
+          Float_t       GetGapThick() const     { return fGapThick;      };
+          Float_t       GetFoilDens() const     { return fFoilDens;      };
+          Float_t       GetGapDens() const      { return fGapDens;       };
+          Double_t      GetFoilOmega() const    { return fFoilOmega;     };
+          Double_t      GetGapOmega() const     { return fGapOmega;      };
+          Float_t       GetTemp() const         { return fTemp / 273.16; };
+          TH1D         *GetSpectrum() const     { return fSpectrum;      };

 
  protected:
 
 
  protected:
 

diff --git a/TRD/AliTRDv1.cxx b/TRD/AliTRDv1.cxx
index 383c8e20778a6a47aabe93024a0c7a00ca4fc4f1..b6b4cd13790822b0b27ac2a888dfa7132cc6b4c7 100644 (file)
--- a/TRD/AliTRDv1.cxx
+++ b/TRD/AliTRDv1.cxx
@@ -15,6 +15,9 @@
 
 /*
 $Log$
 
 /*
 $Log$

+Revision 1.41  2003/04/23 15:19:48  cblume
+Fix bug in absorbtion length of photons
+

 Revision 1.40  2003/04/08 08:14:53  morsch
 AddTrackReference moved to AliModule.
 
 Revision 1.40  2003/04/08 08:14:53  morsch
 AddTrackReference moved to AliModule.
 


@@ -336,27 +339,37 @@ void AliTRDv1::CreateTRhit(Int_t det)
       // Take the absorbtion in the entrance window into account
       Double_t muMy = fTR->GetMuMy(energyMeV);
       sigma = muMy * fFoilDensity;
       // Take the absorbtion in the entrance window into account
       Double_t muMy = fTR->GetMuMy(energyMeV);
       sigma = muMy * fFoilDensity;

-      absLength = gRandom->Exp(-sigma);
-      if (absLength < AliTRDgeometry::MyThick()) continue;
+      if (sigma > 0.0) {
+        absLength = gRandom->Exp(1.0/sigma);
+        if (absLength < AliTRDgeometry::MyThick()) continue;
+      }
+      else {
+        continue;
+      }

 
       // The absorbtion cross sections in the drift gas
       if (fGasMix == 1) {
         // Gas-mixture (Xe/CO2)
         Double_t muXe = fTR->GetMuXe(energyMeV);
         Double_t muCO = fTR->GetMuCO(energyMeV);
 
       // The absorbtion cross sections in the drift gas
       if (fGasMix == 1) {
         // Gas-mixture (Xe/CO2)
         Double_t muXe = fTR->GetMuXe(energyMeV);
         Double_t muCO = fTR->GetMuCO(energyMeV);

-        sigma = (0.85 * muXe + 0.15 * muCO) * fGasDensity;
+        sigma = (0.85 * muXe + 0.15 * muCO) * fGasDensity * fTR->GetTemp();

       }
       else {
         // Gas-mixture (Xe/Isobutane) 
         Double_t muXe = fTR->GetMuXe(energyMeV);
         Double_t muBu = fTR->GetMuBu(energyMeV);
       }
       else {
         // Gas-mixture (Xe/Isobutane) 
         Double_t muXe = fTR->GetMuXe(energyMeV);
         Double_t muBu = fTR->GetMuBu(energyMeV);

-        sigma = (0.97 * muXe + 0.03 * muBu) * fGasDensity;
+        sigma = (0.97 * muXe + 0.03 * muBu) * fGasDensity * fTR->GetTemp();

       }
 
       // The distance after which the energy of the TR photon
       // is deposited.
       }
 
       // The distance after which the energy of the TR photon
       // is deposited.

-      absLength = gRandom->Exp(-sigma);
-      if (absLength > AliTRDgeometry::DrThick()) continue;
+      if (sigma > 0.0) {
+        absLength = gRandom->Exp(1.0/sigma);
+        if (absLength > AliTRDgeometry::DrThick()) continue;
+      }
+      else {
+        continue;
+      }

 
       // The position of the absorbtion
       Float_t posHit[3];
 
       // The position of the absorbtion
       Float_t posHit[3];