RICH/AliRICHParam.cxx

   1 #include "AliRICHParam.h"
   2 #include "AliRICHConst.h"
   3 #include <TMath.h>
   4 #include <TRandom.h>
   5
   6 ClassImp(AliRICHParam)
   7
   8 // RICH main parameters manipulator
   9 //__________________________________________________________________________________________________
  10 AliRICHParam::AliRICHParam()
  11 {//defines the default parameters
  12   Segmentation         (144,160);           //nx,ny  for the whole chamber
  13   DeadZone             (3*cm);              //spacer between PC planes
  14   PadSize              (8.4*mm,8.0*mm);
  15   fWirePitch=PadSizeX()/2;
  16
  17   Size                 (132.6*cm,26*cm,136.7*cm);  //full length, not GEANT half notation
  18   AngleRot             (60);                       //rotation of the whole RICH around Z, deg
  19   Angles               (20,19.5);                  //XY angle, YZ angle  deg
  20   Offset               (490*cm+1.267*cm);          //1.267???????cm distance from IP to the center of module
  21   GapThickness         (8*cm);
  22   ProximityGapThickness(0.4*cm);
  23   QuartzLength         (133*cm);
  24   QuartzWidth          (127.9*cm);
  25   QuartzThickness      (0.5*cm);
  26   OuterFreonLength     (133*cm);
  27   OuterFreonWidth      (41.3*cm);
  28   InnerFreonLength     (133*cm);
  29   InnerFreonWidth      (41.3*cm);
  30   FreonThickness       (1.5*cm);
  31   RadiatorToPads       (80*mm);
  32
  33   ChargeSlope(27.);
  34   ChargeSpreadX(0.18);ChargeSpreadY(0.18);
  35   SigmaIntegration(5.);
  36   MaxAdc(4096);
  37   AlphaFeedback(0.036);
  38   EIonisation(26.e-9);
  39   SqrtKx3(0.77459667);
  40   Kx2(0.962);
  41   Kx4(0.379);
  42   SqrtKy3(0.77459667);
  43   Ky2(0.962);
  44   Ky4(0.379);
  45   Pitch(0.25);
  46   WireSag(1);                 // 1->On, 0->Off
  47   Voltage(2150);              // Should only be 2000, 2050, 2100 or 2150
  48
  49   Recalc();
  50 }//AliRICHParam::named ctor
  51 //__________________________________________________________________________________________________
  52 void AliRICHParam::Recalc()
  53 {//recalculate
  54   fPcSizeX=Nx()*fPadSizeX+2*fDeadZone;
  55   fPcSizeY=Ny()*fPadSizeY+fDeadZone;
  56   fSectorSizeX=(fPcSizeX-2*fDeadZone)/3;
  57   fSectorSizeY=(fPcSizeY-fDeadZone)/2;
  58 }//void AliRICHParam::Recalc()
  59 //__________________________________________________________________________________________________
  60 Int_t AliRICHParam::Sector(Float_t x, Float_t y)const
  61 {//Calculate in which sector is the hit
  62   if(TMath::Abs(x)>fPcSizeX/2 || TMath::Abs(y)>fPcSizeY/2){
  63     Error("Sector","given position is out of active PC area");
  64     return kBad;
  65   }
  66   Int_t sector=kBad;
  67   if(x<=-fSectorSizeX/2-fDeadZone)            sector=1;
  68   if(x>=-fSectorSizeX/2 && x<=fSectorSizeX/2) sector=2;
  69   if(x>= fSectorSizeX/2+fDeadZone)            sector=3;
  70   if(y>= fDeadZone/2)
  71     return sector;
  72   else if(y<=-fDeadZone/2)
  73     return -sector;
  74   else
  75     return kBad;
  76 }//Int_t AliRICHParam::Sector(Float_t x, Float_t y)
  77 //__________________________________________________________________________________________________
  78 Int_t AliRICHParam::L2P(Float_t x, Float_t y, Int_t &iPadX, Int_t &iPadY)const
  79 {//returns pad numbers (iPadX,iPadY) for given point in local coordinates (x,y)
  80 //
  81 // Please check origin of pad numbering !!!
  82   iPadX=kBad;
  83   iPadY=kBad;
  84   Int_t sector=Sector(x,y);
  85   switch(sector){
  86     case -3:
  87       iPadX = Int_t ((x-fDeadZone)/fPadSizeX);
  88       iPadY = Int_t ((y+fDeadZone/2)/fPadSizeY)-1;
  89      break;
  90     case 3:
  91       iPadX = Int_t ((x-fDeadZone)/fPadSizeX);
  92       iPadY = Int_t ((y-fDeadZone/2)/fPadSizeY);
  93      break;
  94     case -2:
  95       iPadX = (x>=0)? iPadX = Int_t (x/fPadSizeX) : iPadX = Int_t (x/fPadSizeX)-1;
  96       iPadY = Int_t ((y+fDeadZone/2)/fPadSizeY)-1;
  97      break;
  98     case 2:
  99       iPadX = (x>=0)? iPadX = Int_t (x/fPadSizeX) : iPadX = Int_t (x/fPadSizeX)-1;
 100       iPadY = Int_t ((y-fDeadZone/2)/fPadSizeY);
 101      break;
 102     case -1:
 103       iPadX = Int_t ((x+fDeadZone)/fPadSizeX)-1;
 104       iPadY = Int_t ((y+fDeadZone/2)/fPadSizeY)-1;
 105      break;
 106     case 1:
 107       iPadX = Int_t ((x+fDeadZone)/fPadSizeX)-1;
 108       iPadY = Int_t ((y-fDeadZone/2)/fPadSizeY);
 109      break;
 110   }//switch
 111
 112   if(iPadY> Ny()) iPadY= Ny();
 113   if(iPadY<-Ny()) iPadY=-Ny();
 114   if(iPadX> Nx()) iPadX= Nx();
 115   if(iPadX<-Nx()) iPadX=-Nx();
 116   return sector;
 117 }//void AliRICHParam::L2P(Float_t x, Float_t y, Int_t &iPadX, Int_t &iPadY)
 118 //__________________________________________________________________________________________________
 119 Float_t AliRICHParam::Gain(Float_t y)
 120 {//Calculates the gain
 121   if(fWireSag){
 122     Float_t gainK=9e-6*TMath::Power(y,4)+2e-7*TMath::Power(y,3)-0.0316*TMath::Power(y,2)-3e-4*y+25.367;
 123     Float_t gain = (ChargeSlope()+ChargeSlope()*gainK/100)*0.9;
 124     return -gain*TMath::Log(gRandom->Rndm());
 125   }else
 126     return -ChargeSlope()*TMath::Log(gRandom->Rndm());
 127 }//Float_t AliRICHParam::IntPH(Float_t yhit)
 128 //__________________________________________________________________________________________________
 129 Float_t AliRICHParam::TotalCharge(Int_t iPID,Float_t eloss,Float_t y)
 130 {//Get number of electrons and return charge
 131
 132   if(iPID==kCerenkov||iPID==kFeedback)
 133     return Gain(y);
 134   else{
 135     Int_t iNelectrons=Int_t(eloss/fEIonisation);if(iNelectrons==0) iNelectrons=1;
 136     Float_t charge=0;
 137     for(Int_t i=1;i<=iNelectrons;i++)
 138       charge-=Gain(y);
 139     return charge;
 140   }
 141 }//Float_t AliRICHParam::TotalCharge(Int_t iPID,Float_t eloss, Float_t y)
 142 //__________________________________________________________________________________________________