RICH/AliRICHParam.h

   1 #ifndef AliRICHParam_h
   2 #define AliRICHParam_h
   3
   4 #include "AliRICHConst.h"
   5 #include <TObject.h>
   6 #include <TMath.h>
   7 #include <TVector3.h>
   8 #include <TRandom.h>
   9
  10 class AliRICHParam :public TObject
  11 {
  12 public:
  13            AliRICHParam()                    {;}
  14   virtual ~AliRICHParam()                    {;}
  15   static Int_t   NpadsX()                   {return 144;}
  16   static Int_t   NpadsY()                   {return 160;}
  17   static Int_t   NpadsXsec()                {return NpadsX()/3;}
  18   static Int_t   NpadsYsec()                {return NpadsY()/2;}
  19   static Double_t DeadZone()                 {return 2.6;}
  20   static Double_t PadSizeX()                 {return 0.84;}
  21   static Double_t PadSizeY()                 {return 0.8;}
  22   static Double_t SectorSizeX()              {return NpadsX()*PadSizeX()/3;}
  23   static Double_t SectorSizeY()              {return NpadsY()*PadSizeY()/2;}
  24   static Double_t PcSizeX()                  {return NpadsX()*PadSizeX()+2*DeadZone();}
  25   static Double_t PcSizeY()                  {return NpadsY()*PadSizeY()+DeadZone();}
  26   static Double_t WirePitch()                {return PadSizeX()/2;}
  27   static Double_t SizeX()                    {return 132.6;}
  28   static Double_t SizeY()                    {return 26;}
  29   static Double_t SizeZ()                    {return 136.7;}
  30   static Double_t Offset()                   {return 490+1.267;}
  31   static Double_t AngleYZ()                  {return 19.5*TMath::DegToRad();}
  32   static Double_t AngleXY()                  {return 20*TMath::DegToRad();}
  33   static Double_t FreonThickness()           {return 1.5;}
  34   static Double_t QuartzThickness()          {return 0.5;}
  35   static Double_t GapThickness()             {return 8.0;}
  36   static Double_t RadiatorToPads()           {return FreonThickness()+QuartzThickness()+GapThickness();}
  37   static Double_t ProximityGapThickness()    {return 0.4;}
  38   static Double_t AnodeCathodeGap()          {return 0.2;}
  39   static Double_t QuartzLength()             {return 133;}
  40   static Double_t QuartzWidth()              {return 127.9;}
  41   static Double_t OuterFreonLength()         {return 133;}
  42   static Double_t OuterFreonWidth()          {return 41.3;}
  43   static Double_t InnerFreonLength()         {return 133;}
  44   static Double_t InnerFreonWidth()          {return 41.3;}
  45   static Double_t IonisationPotential()      {return 26.0e-9;}
  46   static Double_t MathiensonDeltaX()         {return 5*0.18;}
  47   static Double_t MathiensonDeltaY()         {return 5*0.18;}
  48   static Int_t    MaxQdc()                   {return 4095;}
  49   static Double_t QdcSlope(Int_t sec)        {HV(sec);return 27;}
  50   static Double_t AlphaFeedback(Int_t sec)   {HV(sec);return 0.036;}
  51
  52   static Bool_t   IsWireSag()                {return fgIsWireSag;}
  53   static Int_t    HV(Int_t)                  {return fgHV;}
  54   static Double_t AngleRot()                {return fgAngleRot*TMath::DegToRad();}
  55     static void  SetWireSag(Bool_t status)  {fgIsWireSag=status;}
  56     static void  SetHV(Int_t hv)            {fgHV       =hv;}
  57     static void  SetAngleRot(Double_t rot)  {fgAngleRot =rot;}
  58
  59   inline static Double_t Mathienson(Double_t lx1,Double_t lx2,Double_t ly1,Double_t ly2);
  60   inline static void    Loc2Area(TVector3 hitX3,Int_t &padxMin,Int_t &padyMin,Int_t &padxMax,Int_t &padyMax);
  61   inline static Int_t   PadNeighbours(Int_t iPadX,Int_t iPadY,Int_t aListX[4],Int_t aListY[4]);
  62   inline static Int_t   Loc2Pad(Double_t x,Double_t y,Int_t &padx,Int_t &pady);
  63   inline static void    Pad2Loc(Int_t padx,Int_t pady,Double_t &x,Double_t &y);
  64   inline static Double_t GainVariation(Double_t y,Int_t sector);
  65   inline static Int_t   Loc2TotQdc(TVector3 locX3,Double_t eloss,Int_t iPid, Int_t &sector);
  66   inline static Double_t Loc2PadFrac(TVector3 locX3,Int_t padx,Int_t pady);
  67
  68   inline  void   SigGenInit(Double_t x,Double_t y);
  69   inline  Bool_t SigGenCond(Double_t x,Double_t y);
  70   inline static Int_t   Loc2Sec(Double_t &x,Double_t &y);
  71   inline static Int_t   Pad2Sec(Int_t &padx,Int_t &pady);
  72
  73 protected:
  74   static Bool_t  fgIsWireSag;      //is wire sagitta taken into account
  75   static Int_t   fgHV;             //HV applied to anod wires
  76   static Double_t fgAngleRot;       //rotation of RICH from up postion (0,0,490)cm
  77
  78   ClassDef(AliRICHParam,4)    //RICH main parameters
  79 };
  80 //__________________________________________________________________________________________________
  81 Int_t AliRICHParam::PadNeighbours(Int_t iPadX,Int_t iPadY,Int_t listX[4],Int_t listY[4])
  82 {
  83   Int_t nPads=0;
  84   if(iPadY<NpadsY()){listX[nPads]=iPadX;   listY[nPads]=iPadY+1; nPads++;}
  85   if(iPadX<NpadsX()){listX[nPads]=iPadX+1; listY[nPads]=iPadY;   nPads++;}
  86   if(iPadY>1)       {listX[nPads]=iPadX;   listY[nPads]=iPadY-1; nPads++;}
  87   if(iPadX>1)       {listX[nPads]=iPadX-1; listY[nPads]=iPadY;   nPads++;}
  88   return nPads;
  89 }//Pad2ClosePads()
  90 //__________________________________________________________________________________________________
  91 Int_t AliRICHParam::Loc2Sec(Double_t &x,Double_t &y)
  92 {//Determines sector for a given hit (x,y) and trasform this point to the local system of that sector.
  93   Int_t sector=kBad;
  94   Double_t x1=-0.5*PcSizeX();      Double_t x2=-0.5*SectorSizeX()-DeadZone();  Double_t x3=-0.5*SectorSizeX();
  95   Double_t x4= 0.5*SectorSizeX();  Double_t x5= 0.5*SectorSizeX()+DeadZone();  Double_t x6= 0.5*PcSizeX();
  96
  97   if     (x>=x1&&x<=x2)    {sector=1;x+=0.5*PcSizeX();}
  98   else if(x>=x3&&x<=x4)    {sector=2;x+=0.5*SectorSizeX();}
  99   else if(x>=x5&&x<=x6)    {sector=3;x-=0.5*SectorSizeX()+DeadZone();}
 100   else if(x< x1||x> x6)    {return kBad;}
 101   else                                                        {return kBad;} //in dead zone
 102
 103   if     (y>=-0.5*PcSizeY()   &&y<=-0.5*DeadZone())  {y+=0.5*PcSizeY();  return -sector;}
 104   else if(y> -0.5*DeadZone()  &&y<  0.5*DeadZone())  {return kBad;} //in dead zone
 105   else if(y>= 0.5*DeadZone()  &&y<= 0.5*PcSizeY())   {y-=0.5*DeadZone(); return  sector;}
 106   else                                               {return kBad;}
 107 }//Loc2Sec(Double_t x, Double_t y)
 108 //__________________________________________________________________________________________________
 109 Int_t AliRICHParam::Pad2Sec(Int_t &padx, Int_t &pady)
 110 {//Determines sector for a given pad (padx,pady) and trasform this point to the local system of that sector.
 111   Int_t sector=kBad;
 112   if     (padx>=1            &&padx<=NpadsXsec())      {sector=1;}
 113   else if(padx> NpadsXsec()  &&padx<=NpadsXsec()*2)    {sector=2;padx-=NpadsXsec();}
 114   else if(padx> NpadsXsec()*2&&padx<=NpadsX())         {sector=3;padx-=NpadsXsec()*2;}
 115   else                                                 {return kBad;}
 116
 117   if     (pady>=1         &&pady<= NpadsYsec())     {return -sector;}
 118   else if(pady>NpadsYsec()&&pady<= NpadsY())        {pady-=NpadsYsec();return sector;}
 119   else                                              {return kBad;}
 120 }//Pad2Sec()
 121 //__________________________________________________________________________________________________
 122 Int_t AliRICHParam::Loc2Pad(Double_t x, Double_t y, Int_t &padx, Int_t &pady)
 123 {//returns pad numbers (iPadX,iPadY) for given point in local coordinates (x,y)
 124  //count starts in lower left corner from 1,1 to 144,180
 125
 126   padx=pady=kBad;
 127   Int_t sector=Loc2Sec(x,y);
 128   if(sector==kBad) return sector;
 129
 130   padx=Int_t(x/PadSizeX())+1;
 131   if(padx>NpadsXsec())            padx= NpadsXsec();
 132   if(sector==2||sector==-2)       padx+=NpadsXsec();
 133   else if(sector==3||sector==-3)  padx+=NpadsXsec()*2;
 134
 135   pady=Int_t(y/PadSizeY())+1;
 136   if(pady>NpadsYsec())            padx= NpadsYsec();
 137   if(sector>0)                    pady+=NpadsYsec();
 138
 139   return sector;
 140 }//Loc2Pad()
 141 //__________________________________________________________________________________________________
 142 void AliRICHParam::Pad2Loc(Int_t padx,Int_t pady,Double_t &x,Double_t &y)
 143 {
 144   Int_t sector=Pad2Sec(padx,pady);
 145   if(sector>0)
 146     y=0.5*DeadZone()+pady*PadSizeY()-0.5*PadSizeY();
 147   else{
 148     sector=-sector;
 149     y=-0.5*PcSizeY()+pady*PadSizeY()-0.5*PadSizeY();
 150   }
 151   if(sector==1)
 152     x=-0.5*PcSizeX()+padx*PadSizeX()-0.5*PadSizeX();
 153   else if(sector==2)
 154     x=-0.5*SectorSizeX()+padx*PadSizeX()-0.5*PadSizeX();
 155   else
 156     x= 0.5*SectorSizeX()+DeadZone()+padx*PadSizeX()-0.5*PadSizeX();
 157   return;
 158 }//Pad2Loc()
 159 //__________________________________________________________________________________________________
 160 Double_t AliRICHParam::GainVariation(Double_t y,Int_t sector)
 161 {
 162   if(IsWireSag()){
 163     if(y>0) y-=SectorSizeY()/2; else  y+=SectorSizeY()/2;
 164     switch(HV(sector)){
 165       case 2150:
 166       default:
 167         return 9e-6*TMath::Power(y,4)+2e-7*TMath::Power(y,3)-0.0316*TMath::Power(y,2)-3e-4*y+25.367;//%
 168     }
 169   }else
 170     return 0;
 171 }
 172 //__________________________________________________________________________________________________
 173 Int_t AliRICHParam::Loc2TotQdc(TVector3 x3,Double_t eloss,Int_t iPid,Int_t &sector)
 174 {//calculates the total charge produced by the hit given in local refenrence system
 175   Double_t x=x3.X(),y=x3.Y();
 176
 177   sector=Loc2Sec(x,y);
 178
 179   Double_t gain=QdcSlope(sector)*(1+GainVariation(x3.Y(),sector)/100);
 180
 181
 182   if(iPid>50000){//it's photon => 1 electron
 183     return Int_t(gain*-TMath::Log(gRandom->Rndm()));
 184   }else{//it's MIP
 185     Int_t iNelectrons=Int_t(eloss/IonisationPotential());
 186     if(iNelectrons==0) return 0;
 187     Double_t qdc=0;
 188     for(Int_t i=1;i<=iNelectrons;i++) qdc+=gain*-TMath::Log(gRandom->Rndm());
 189     return Int_t(qdc);
 190   }
 191 }
 192 //__________________________________________________________________________________________________
 193 Double_t AliRICHParam::Loc2PadFrac(TVector3 hitX3,Int_t padx,Int_t pady)
 194 {//
 195   Double_t padXcenter=0,padYcenter=0;  Pad2Loc(padx,pady,padXcenter,padYcenter);
 196
 197   //correction to the position of the nearest wire
 198
 199   Double_t normXmin=(hitX3.X()-padXcenter-PadSizeX()/2)  /AnodeCathodeGap();
 200   Double_t normXmax=(hitX3.X()-padXcenter+PadSizeX()/2)  /AnodeCathodeGap();
 201   Double_t normYmin=(hitX3.Y()-padYcenter-PadSizeY()/2)  /AnodeCathodeGap();
 202   Double_t normYmax=(hitX3.Y()-padYcenter+PadSizeY()/2)  /AnodeCathodeGap();
 203
 204   return Mathienson(normXmin,normYmin,normXmax,normYmax);
 205 }//Loc2PadQdc()
 206 //__________________________________________________________________________________________________
 207 Double_t AliRICHParam::Mathienson(Double_t xMin,Double_t yMin,Double_t xMax,Double_t yMax)
 208 {//see NIM A370(1988)602-603
 209   const Double_t SqrtKx3=0.77459667;const Double_t Kx2=0.962;const Double_t Kx4=0.379;
 210   const Double_t SqrtKy3=0.77459667;const Double_t Ky2=0.962;const Double_t Ky4=0.379;
 211
 212   Double_t ux1=SqrtKx3*TMath::TanH(Kx2*xMin);
 213   Double_t ux2=SqrtKx3*TMath::TanH(Kx2*xMax);
 214   Double_t uy1=SqrtKy3*TMath::TanH(Ky2*yMin);
 215   Double_t uy2=SqrtKy3*TMath::TanH(Ky2*yMax);
 216   return 4*Kx4*(TMath::ATan(ux2)-TMath::ATan(ux1))*Ky4*(TMath::ATan(uy2)-TMath::ATan(uy1));
 217 }
 218 //__________________________________________________________________________________________________
 219 void AliRICHParam::Loc2Area(TVector3 hitX3,Int_t &iPadXmin,Int_t &iPadYmin,Int_t &iPadXmax,Int_t &iPadYmax)
 220 {//calculates the area of disintegration for a given hit. Area is a rectangulare set pf pads
 221  //defined by its left-down and right-up coners
 222   //  hitX3.SetX(Shift2NearestWire(hitX3.X());
 223   Loc2Pad(hitX3.X()-MathiensonDeltaX(),hitX3.X()-MathiensonDeltaY(),iPadXmin,iPadYmin);
 224   Loc2Pad(hitX3.X()+MathiensonDeltaX(),hitX3.X()+MathiensonDeltaY(),iPadXmax,iPadYmax);
 225 }//
 226 #endif //AliRICHParam_h