#define AliRICHParam_h
#include <TObject.h>
-#include "AliRICHConst.h"
+#include <TMath.h>
+#include <TVector2.h>
+#include <TRandom.h>
+#include <TError.h>
+static const int kNCH=7; //number of RICH chambers
+static const int kNpadsX = 144; //number of pads along X in single chamber
+static const int kNpadsY = 160; //number of pads along Y in single chamber
+static const int kBad=-101; //useful static const to mark initial (uninitalised) values
+static const int kNsectors=6; // nb. of sectors per chamber
+
+static const int kadc_satm = 4096; //dynamic range (10 bits)
+static const int kCerenkov=50000050; //??? go to something more general like TPDGCode
+static const int kFeedback=50000051; //??? go to something more general like TPDGCode
+
class AliRICHParam :public TObject
{
public:
- AliRICHParam();
- virtual ~AliRICHParam() {;}
-
- inline Int_t Neighbours(Int_t iPadX,Int_t iPadY,Int_t aListX[4],Int_t aListY[4])const; //pad->neibours
- inline void SigGenInit(Float_t x,Float_t y);
- inline Bool_t SigGenCond(Float_t x,Float_t y);
- static Int_t Local2Pad(Float_t x,Float_t y,Int_t &padx,Int_t &pady); //(x,y)->(padx,pady), returns sector code
- static Int_t Local2PadX(Float_t x,Float_t y) {Int_t padx,pady;Local2Pad(x,y,padx,pady);return padx;}//(x,y)->padx
- static Int_t Local2PadY(Float_t x,Float_t y) {Int_t padx,pady;Local2Pad(x,y,padx,pady);return pady;}//(x,y)->pady
- static void Pad2Local(Int_t padx,Int_t pady,Float_t &x,Float_t &y); //(padx,pady)->(x,y)
- static Int_t LocalX2Wire(Float_t x) {return Int_t((x+PcSizeX()/2)/WirePitch())+1;} //x->wire number
- static Float_t Wire2LocalX(Int_t iWireN) {return iWireN*WirePitch()-PcSizeX()/2;} //wire number->x
+ AliRICHParam() {;}
+ virtual ~AliRICHParam() {;}
+ static const Int_t NpadsX() {return kNpadsX;} //pads along X in chamber
+ static const Int_t NpadsY() {return kNpadsY;} //pads along Y in chamber
+ static Int_t NpadsXsec() {return NpadsX()/3;} //pads along X in sector
+ static Int_t NpadsYsec() {return NpadsY()/2;} //pads along Y in sector
+ static Double_t DeadZone() {return 2.6;} //dead zone size in cm
+ static Double_t PadSizeX() {return 0.84;} //pad size x in cm
+ static Double_t PadSizeY() {return 0.8;} //pad size y in cm
+ static Double_t SectorSizeX() {return NpadsX()*PadSizeX()/3;} //sector size x in cm
+ static Double_t SectorSizeY() {return NpadsY()*PadSizeY()/2;} //sector size y in cm
+ static Double_t PcSizeX() {return NpadsX()*PadSizeX()+2*DeadZone();} //photocathode size x in cm
+ static Double_t PcSizeY() {return NpadsY()*PadSizeY()+DeadZone();} //photocathode size y in cm
+ static Double_t WirePitch() {return PadSizeX()/2;} //distance between anode wires
+ static Double_t SizeX() {return 132.6;}
+ static Double_t SizeY() {return 26;}
+ static Double_t SizeZ() {return 136.7;}
+ static Double_t Offset() {return 490+1.267;} //distance from IP to center of chamber in cm
+ static Double_t AngleYZ() {return 19.5*TMath::DegToRad();} //angle between chambers in YZ plane, rad
+ static Double_t AngleXY() {return 20*TMath::DegToRad();} //angle between chambers in XY plane, rad
+ static Double_t AngleRot() {return fgAngleRot*TMath::DegToRad();} //RICH rotation around Z, rad
+ static Double_t FreonThickness() {return 1.5;}
+ static Double_t QuartzThickness() {return 0.5;}
+ static Double_t GapThickness() {return 8.0;}
+ static Double_t RadiatorToPads() {return FreonThickness()+QuartzThickness()+GapThickness();}
+ static Double_t ProximityGap() {return 0.445;}
+ static Double_t AnodeCathodeGap() {return 0.2;}
+ static Double_t QuartzLength() {return 133;}
+ static Double_t QuartzWidth() {return 127.9;}
+ static Double_t OuterFreonLength() {return 133;}
+ static Double_t OuterFreonWidth() {return 41.3;}
+ static Double_t InnerFreonLength() {return 133;}
+ static Double_t InnerFreonWidth() {return 41.3;}
+ static Double_t IonisationPotential() {return 26.0e-9;}
+ static TVector2 MathiesonDelta() {return TVector2(5*0.18,5*0.18);}
+ static Int_t MaxQdc() {return 4095;}
+ static Double_t AlphaFeedback(Int_t sec) {HV(sec);return 0.036;}
- Float_t Gain(Float_t y); //Returns total charge induced by single photon
- Float_t TotalCharge(Int_t iPID,Float_t eloss,Float_t y); //Returns total charge induced by particle lost eloss GeV
- static Float_t AssignChargeToPad(Float_t hx,Float_t hy, Int_t px, Int_t py); //Returns charge assigned to given pad for a given hit
- void FirstPad(Float_t x,Float_t y);
-
- static Float_t AnodeCathodeGap() {return 0.2;}
-
- static Int_t NpadsX() {return 144;}
- static Int_t NpadsY() {return 160;}
- static Int_t NpadsXsec() {return NpadsX()/3;}
- static Int_t NpadsYsec() {return NpadsY()/2;}
- static Float_t DeadZone() {return 2.6;}
- static Float_t PadSizeX() {return 0.84;}
- static Float_t PadSizeY() {return 0.8;}
- static Float_t SectorSizeX() {return NpadsX()*PadSizeX()/3;}
- static Float_t SectorSizeY() {return NpadsY()*PadSizeY()/2;}
- static Float_t PcSizeX() {return NpadsX()*PadSizeX()+2*DeadZone();}
- static Float_t PcSizeY() {return NpadsY()*PadSizeY()+DeadZone();}
- static Float_t WirePitch() {return PadSizeX()/2;}
-
- void Size(Float_t x,Float_t y,Float_t z){fSizeX=x;fSizeY=y;fSizeZ=z;}
- void GeantSize(Float_t *pArr) const{pArr[0]=fSizeX/2;pArr[1]=fSizeY/2;pArr[2]=fSizeZ/2;}
- Float_t SizeX() const{return fSizeX;}
- Float_t SizeY() const{return fSizeY;}
- Float_t SizeZ() const{return fSizeZ;}
- static Float_t Offset() {return 490+1.267;}
- static Float_t AngleYZ() {return 19.5*TMath::DegToRad();}
- static Float_t AngleXY() {return 20*TMath::DegToRad();}
- static void AngleRot(Float_t angle) { fgAngleRot=angle;}
- static Float_t AngleRot() {return fgAngleRot*kD2r;}
- static Float_t GapThickness() {return 8.0;}
- void ProximityGapThickness(Float_t a) { fProximityGapThickness=a;}
- Float_t ProximityGapThickness() const{return fProximityGapThickness;}
- void QuartzLength(Float_t a) { fQuartzLength=a;}
- Float_t QuartzLength() const{return fQuartzLength;}
- void QuartzWidth(Float_t a) { fQuartzWidth=a;}
- Float_t QuartzWidth() const{return fQuartzWidth;}
- static Float_t QuartzThickness() {return 0.5;}
- void OuterFreonLength(Float_t a) { fOuterFreonLength=a;}
- Float_t OuterFreonLength() const{return fOuterFreonLength;}
- void OuterFreonWidth(Float_t a) { fOuterFreonWidth=a;}
- Float_t OuterFreonWidth() const{return fOuterFreonWidth;}
- void InnerFreonLength(Float_t a) { fInnerFreonLength=a;}
- Float_t InnerFreonLength() const{return fInnerFreonLength;}
- void InnerFreonWidth(Float_t a) { fInnerFreonWidth=a;}
- Float_t InnerFreonWidth() const{return fInnerFreonWidth;}
- static Float_t FreonThickness() {return 1.5;}
- static Float_t RadiatorToPads() {return FreonThickness()+QuartzThickness()+GapThickness();}
-
- void SigmaIntegration(Float_t a) { fSigmaIntegration=a;}
- Float_t SigmaIntegration() const{return fSigmaIntegration;}
- void ChargeSpreadX(Float_t a) { fChargeSpreadX=a;}
- Float_t ChargeSpreadX() const{return fChargeSpreadX;}
- void ChargeSpreadY(Float_t a) { fChargeSpreadY=a;}
- Float_t ChargeSpreadY() const{return fChargeSpreadY;}
- Float_t AreaX() const{return fSigmaIntegration*fChargeSpreadX;}
- Float_t AreaY() const{return fSigmaIntegration*fChargeSpreadY;}
- void ChargeSlope(Float_t a) { fChargeSlope=a;}
- Float_t ChargeSlope() {return fChargeSlope;}
- void MaxAdc(Int_t a) { fMaxAdc=a;}
- Int_t MaxAdc() const{return fMaxAdc;}
- void AlphaFeedback(Float_t a) { fAlphaFeedback=a;}
- Float_t AlphaFeedback() const{return fAlphaFeedback;}
- void EIonisation(Float_t a) { fEIonisation=a;}
- Float_t EIonisation() const{return fEIonisation;}
- static Float_t SqrtKx3() {return 0.77459667;}
- static Float_t Kx2() {return 0.962;}
- static Float_t Kx4() {return 0.379;}
- static Float_t SqrtKy3() {return 0.77459667;}
- static Float_t Ky2() {return 0.962;}
- static Float_t Ky4() {return 0.379;}
+ static Bool_t IsResolveClusters() {return fgIsResolveClusters;} //go after resolved clusters?
+ static Bool_t IsWireSag() {return fgIsWireSag;} //take wire sagita in account?
+ static Int_t HV(Int_t sector) {
+ if (sector>=1 && sector <=6)
+ return fgHV[sector-1];
+ else {
+ ::Error("HV","Wrong sector %d",sector);
+ return kBad;
+ }
+ } //high voltage for this sector
+ static void IsResolveClusters(Bool_t a) {fgIsResolveClusters=a;}
+ static void SetWireSag(Bool_t status) {fgIsWireSag=status;}
+ static void SetHV(Int_t sector,Int_t hv){fgHV[sector-1]=hv;}
+ static void SetAngleRot(Double_t rot) {fgAngleRot =rot;}
- void WireSag(Int_t a) { fWireSag=a;}
- void Voltage(Int_t a) { fVoltage=a;}
- Float_t Voltage() const{return fVoltage;}
+ inline static void Loc2Area(TVector2 x2,Int_t &padxMin,Int_t &padyMin,Int_t &padxMax,Int_t &padyMax); //
+ inline static Int_t Loc2Pad(TVector2 x2,Int_t &padx,Int_t &pady); //return sector and pad
+ inline static TVector2 Pad2Loc(Int_t padx,Int_t pady); //return center of the pad
+ static Int_t Sector(Int_t padx,Int_t pady) {return Pad2Sec(padx,pady);} //sector of this pad
+ static Int_t Sector(TVector2 x2) {int x,y;return Loc2Pad(x2,x,y);} //sector of this point
+ inline static Int_t PadNeighbours(Int_t iPadX,Int_t iPadY,Int_t aListX[4],Int_t aListY[4]); //number of neighbours for this pad
+ inline static TVector2 ShiftToWirePos(TVector2 x2); //shift to the nearest wire
+
+ inline static Double_t Mathieson(Double_t lx1,Double_t lx2,Double_t ly1,Double_t ly2); //Mathienson integral over these limits
+ inline static Double_t GainSag(Double_t y,Int_t sector); //gain variations in %
+ inline static Double_t QdcSlope(Int_t sec); //weight of electon in QDC channels
+ inline static Double_t Gain(TVector2 x2); //gain for point in ChRS
+ inline static Double_t FracQdc(TVector2 x2,Int_t padx,Int_t pady); //charge fraction to pad from hit
+ inline static Int_t TotQdc(TVector2 x2,Double_t eloss); //total charge for hit eloss=0 for photons
+ inline Bool_t IsOverTh(Int_t iChamber, Int_t x, Int_t y, Double_t q); //
+ static Int_t NsigmaTh() {return fgNsigmaTh;} //
+ static Float_t SigmaThMean() {return fgSigmaThMean;} //
+ static Float_t SigmaThSpread() {return fgSigmaThSpread;} //
+ void GenSigmaThMap(); //generate pedestal map
+ static void Print();
protected:
- static Int_t Local2Sector(Float_t &x,Float_t &y); //(x,y)->sector
- static Int_t Pad2Sector(Int_t &padx,Int_t &pady); //(padx,pady)->sector
+ inline static Int_t Loc2Sec(TVector2 &x2); //return sector, x2->Sector RS
+ inline static Int_t Pad2Sec(Int_t &padx,Int_t &pady); //return sector, (padx,pady)->Sector RS
+ static Bool_t fgIsWireSag; //is wire sagitta taken into account
+ static Bool_t fgIsResolveClusters; //performs declustering or not
+ static Int_t fgHV[6]; //HV applied to anod wires
+ static Double_t fgAngleRot; //rotation of RICH from up postion (0,0,490)cm
+ static Float_t fSigmaThMap[kNCH][kNpadsX][kNpadsY]; //sigma of the pedestal distributions for all pads
+ static Int_t fgNsigmaTh; //n. of sigmas to cut for zero suppression
+ static Float_t fgSigmaThMean; //sigma threshold value
+ static Float_t fgSigmaThSpread; //spread of sigma
+ ClassDef(AliRICHParam,4) //RICH main parameters
+};
+//__________________________________________________________________________________________________
+Int_t AliRICHParam::PadNeighbours(Int_t iPadX,Int_t iPadY,Int_t listX[4],Int_t listY[4])
+{
+// Determines all the neighbouring pads for the given one. Returns total amount of these pads.
+// Dead zones are taken into account.
+ Int_t nPads=0;
+ if(iPadY!=NpadsY()&&iPadY!=NpadsYsec()) {listX[nPads]=iPadX; listY[nPads]=iPadY+1; nPads++;}
+ if(iPadX!=NpadsXsec()&&iPadX!=2*NpadsXsec()&&iPadX!=NpadsX()){listX[nPads]=iPadX+1; listY[nPads]=iPadY; nPads++;}
+ if(iPadY!=1&&iPadY!=NpadsYsec()+1) {listX[nPads]=iPadX; listY[nPads]=iPadY-1; nPads++;}
+ if(iPadX!=1&&iPadX!=NpadsXsec()+1&&iPadX!=2*NpadsXsec()+1) {listX[nPads]=iPadX-1; listY[nPads]=iPadY; nPads++;}
+
+ return nPads;
+}//Pad2ClosePads()
+//__________________________________________________________________________________________________
+Int_t AliRICHParam::Loc2Sec(TVector2 &x2)
+{
+// Determines sector containing the given point and trasform this point to the local system of that sector.
+// Returns sector code: 1 2 3
+// 4 5 6
+ Int_t sector=kBad;
+ Double_t p1=-0.5*PcSizeX(); Double_t p2=-0.5*SectorSizeX()-DeadZone(); Double_t p3=-0.5*SectorSizeX();
+ Double_t p4= 0.5*SectorSizeX(); Double_t p5= 0.5*SectorSizeX()+DeadZone(); Double_t p6= 0.5*PcSizeX();
+ Double_t x,y;
+ if (x2.X()>=p1&&x2.X()<=p2) {sector=1;x=x2.X()+0.5*PcSizeX();}
+ else if(x2.X()>=p3&&x2.X()<=p4) {sector=2;x=x2.X()+0.5*SectorSizeX();}
+ else if(x2.X()>=p5&&x2.X()<=p6) {sector=3;x=x2.X()-0.5*SectorSizeX()-DeadZone();}
+ else {return kBad;} //in dead zone or out of chamber
- Int_t fCurrentPadX,fCurrentPadY; //???
- Int_t fCurrentWire; //???
-
- Float_t fSizeX; Float_t fSizeY; Float_t fSizeZ; //chamber outer size, cm
- static Float_t fgAngleRot; //azimuthal rotation XY plane, deg
- Float_t fProximityGapThickness; //proximity gap thickness, cm
- Float_t fQuartzLength; Float_t fQuartzWidth; //quartz window size, cm
- Float_t fOuterFreonLength; Float_t fOuterFreonWidth; //freon box outer size, cm
- Float_t fInnerFreonLength; Float_t fInnerFreonWidth; //freon box inner size, cm
+ if (x2.Y()>=-0.5*PcSizeY() &&x2.Y()<=-0.5*DeadZone()) {y=x2.Y()+0.5*PcSizeY();sector+=3;} //sectors 4,5,6
+ else if(x2.Y()> -0.5*DeadZone()&&x2.Y()< 0.5*DeadZone()) {return kBad;} //in dead zone
+ else if(x2.Y()>= 0.5*DeadZone()&&x2.Y()<= 0.5*PcSizeY()) {y=x2.Y()-0.5*DeadZone();} //sectors 1,2,3
+ else {return kBad;} //out of chamber
+ x2.Set(x,y);
+ return sector;
+}//Loc2Sec(Double_t x, Double_t y)
+//__________________________________________________________________________________________________
+Int_t AliRICHParam::Loc2Pad(TVector2 x2,Int_t &padx,Int_t &pady)
+{
+// Determines pad number (padx,pady) containing the given point x2 defined the chamber RS.
+// Pad count starts in lower left corner from 1,1 to 144,160 in upper right corner of a chamber.
+// Returns sector number of the determined pad.
+ Int_t sector=Loc2Sec(x2);//trasforms x2 to sector reference system
+ if(sector==kBad) {padx=pady=kBad; return sector;}
- Float_t fChargeSlope; //Slope of the charge distribution
- Float_t fChargeSpreadX; //Width of the charge distribution in x
- Float_t fChargeSpreadY; //Width of the charge distribution in y
- Float_t fSigmaIntegration; //Number of sigma's used for charge distribution
- Float_t fAlphaFeedback; //Feedback photons coefficient
- Float_t fEIonisation; //Mean ionisation energy
- Int_t fMaxAdc; //Maximum ADC channel
- Int_t fWireSag; //Flag to turn on/off (0/1) wire sag
- Int_t fVoltage; //Working voltage (2000, 2050, 2100, 2150)
+ padx=Int_t(x2.X()/PadSizeX())+1; if(padx>NpadsXsec()) padx= NpadsXsec();
+ if(sector==2||sector==5) padx+= NpadsXsec(); // 1 2 3
+ if(sector==3||sector==6) padx+=2*NpadsXsec(); // 4 5 6
- ClassDef(AliRICHParam,2) //RICH main parameters
-};
+ pady=Int_t(x2.Y()/PadSizeY())+1; if(pady>NpadsYsec()) pady= NpadsYsec();
+ if(sector<4) pady+=NpadsYsec();
+ return sector;
+}
+//__________________________________________________________________________________________________
+Int_t AliRICHParam::Pad2Sec(Int_t &padx, Int_t &pady)
+{
+// Determines sector containing the given pad (padx,pady) and trasform it to the local RS of that sector.
+ Int_t sector=kBad;
+ if (padx>=1 &&padx<=NpadsXsec()) {sector=1;}
+ else if(padx> NpadsXsec() &&padx<=NpadsXsec()*2) {sector=2;padx-=NpadsXsec();}
+ else if(padx> NpadsXsec()*2&&padx<=NpadsX()) {sector=3;padx-=NpadsXsec()*2;}
+ else {return kBad;}
+
+ if (pady>=1 &&pady<=NpadsYsec()) {return sector+3;}
+ else if(pady>NpadsYsec() &&pady<=NpadsY()) {pady-=NpadsYsec();return sector;}
+ else {return kBad;}
+}//Pad2Sec()
+//__________________________________________________________________________________________________
+TVector2 AliRICHParam::Pad2Loc(Int_t padx,Int_t pady)
+{
+// Returns position of the center of the given pad (padx,pady) in local RS of the chamber
+ Int_t sector=Pad2Sec(padx,pady);//shifts to sector RS
+ if(sector==kBad) return TVector2(-101,-101);
+ Double_t x,y;
+ if(sector<=3)
+ y=0.5*DeadZone()+pady*PadSizeY()-0.5*PadSizeY(); // 1 2 3
+ else{ // 4 5 6
+ y=-0.5*PcSizeY()+pady*PadSizeY()-0.5*PadSizeY();
+ }
+ if(sector==1||sector==4)
+ x=-0.5*PcSizeX()+padx*PadSizeX()-0.5*PadSizeX();
+ else if(sector==2||sector==5)
+ x=-0.5*SectorSizeX()+padx*PadSizeX()-0.5*PadSizeX();
+ else
+ x= 0.5*SectorSizeX()+DeadZone()+padx*PadSizeX()-0.5*PadSizeX();
+ return TVector2(x,y);
+}
+//__________________________________________________________________________________________________
+Double_t AliRICHParam::GainSag(Double_t y,Int_t sector)
+{
+// Returns % of gain variation due to wire sagita.
+// All cureves are parametrized per sector basis, so y must be scaled to the Sector RS.
+ if(y>0) y-=SectorSizeY()/2; else y+=SectorSizeY()/2;
+ switch(HV(sector)){
+ case 2150: return 9e-6*TMath::Power(y,4)+2e-7*TMath::Power(y,3)-0.0316*TMath::Power(y,2)-3e-4*y+25.367;//%
+ case 2100: return 8e-6*TMath::Power(y,4)+2e-7*TMath::Power(y,3)-0.0283*TMath::Power(y,2)-2e-4*y+23.015;
+ case 2050: return 7e-6*TMath::Power(y,4)+1e-7*TMath::Power(y,3)-0.0254*TMath::Power(y,2)-2e-4*y+20.888;
+ case 2000: return 6e-6*TMath::Power(y,4)+8e-8*TMath::Power(y,3)-0.0227*TMath::Power(y,2)-1e-4*y+18.961;
+ default: return 0;
+ }
+}
//__________________________________________________________________________________________________
-void AliRICHParam::SigGenInit(Float_t x,Float_t y)
-{//Initialises pad and wire position during stepping
- Local2Pad(x,y,fCurrentPadX,fCurrentPadY);
- fCurrentWire= (x>0) ? Int_t(x/WirePitch())+1 : Int_t(x/WirePitch())-1 ;
+Double_t AliRICHParam::QdcSlope(Int_t sec)
+{
+// Returns number of QDC channels per single electron at the unknown yet ???? point for a given sector
+ switch(sec){
+ case kBad: return 0;
+ default: return 27;
+ }
}
//__________________________________________________________________________________________________
-Bool_t AliRICHParam::SigGenCond(Float_t x,Float_t y)
-{//Signal will be generated if particle crosses pad boundary or boundary between two wires.
- Int_t curPadX,curPadY;
- Local2Pad(x,y,curPadX,curPadY);
- Int_t currentWire=(x>0) ? Int_t(x/WirePitch())+1 : Int_t(x/WirePitch())-1;
- if((curPadX != fCurrentPadX) || (curPadY != fCurrentPadY) || (currentWire!=fCurrentWire))
- return kTRUE;
+Double_t AliRICHParam::Gain(TVector2 x2)
+{
+//
+ if(IsWireSag())
+ return QdcSlope(Sector(x2))*(1+GainSag(x2.Y(),Sector(x2))/100);
else
- return kFALSE;
-}//Bool_t AliRICHParam::SigGenCond(Float_t x,Float_t y)
+ return QdcSlope(Sector(x2));
+}
//__________________________________________________________________________________________________
-Int_t AliRICHParam::Neighbours(Int_t iPadX,Int_t iPadY,Int_t listX[4],Int_t listY[4])const
+Int_t AliRICHParam::TotQdc(TVector2 x2,Double_t eloss)
{
- listX[0]=iPadX; listY[0]=iPadY-1;
- listX[1]=iPadX+1; listY[1]=iPadY;
- listX[2]=iPadX; listY[2]=iPadY+1;
- listX[3]=iPadX-1; listY[3]=iPadY;
- return 4;
+// Calculates the total charge produced by the eloss in point x2 (Chamber RS).
+// Returns this change parametrised in QDC channels.
+// eloss=0 means photons which provided for only 1 electron
+// eloss > 0 for Mip
+ if(Sector(x2)==kBad) return 0; //hit in the dead zone
+ Int_t iNelectrons=Int_t(eloss/IonisationPotential()); if(iNelectrons==0) iNelectrons=1;
+ Double_t qdc=0;
+ for(Int_t i=1;i<=iNelectrons;i++) qdc+=-Gain(x2)*TMath::Log(gRandom->Rndm());
+ return Int_t(qdc);
}
//__________________________________________________________________________________________________
+Double_t AliRICHParam::FracQdc(TVector2 x2,Int_t padx,Int_t pady)
+{
+// Calculates the charge fraction for a given pad (padx,pady) from the given hit point.
+// Mathieson distribution integrated is used.
+ TVector2 center2=Pad2Loc(padx,pady);//gives center of requested pad
+ Double_t normXmin=(x2.X()-center2.X()-PadSizeX()/2) /AnodeCathodeGap();
+ Double_t normXmax=(x2.X()-center2.X()+PadSizeX()/2) /AnodeCathodeGap();
+ Double_t normYmin=(x2.Y()-center2.Y()-PadSizeY()/2) /AnodeCathodeGap();
+ Double_t normYmax=(x2.Y()-center2.Y()+PadSizeY()/2) /AnodeCathodeGap();
+
+ if(Sector(x2)!=Sector(padx,pady)) return 0;//requested pad does not belong to the sector of given point
+ else return Mathieson(normXmin, normYmin, normXmax, normYmax);
+}
+//__________________________________________________________________________________________________
+Double_t AliRICHParam::Mathieson(Double_t xMin,Double_t yMin,Double_t xMax,Double_t yMax)
+{
+// All arguments are parametrised according to NIM A370(1988)602-603
+// Returns a charge fraction.
+ const Double_t kSqrtKx3=0.77459667;const Double_t kX2=0.962;const Double_t kX4=0.379;
+ const Double_t kSqrtKy3=0.77459667;const Double_t kY2=0.962;const Double_t kY4=0.379;
+
+ Double_t ux1=kSqrtKx3*TMath::TanH(kX2*xMin);
+ Double_t ux2=kSqrtKx3*TMath::TanH(kX2*xMax);
+ Double_t uy1=kSqrtKy3*TMath::TanH(kY2*yMin);
+ Double_t uy2=kSqrtKy3*TMath::TanH(kY2*yMax);
+ return 4*kX4*(TMath::ATan(ux2)-TMath::ATan(ux1))*kY4*(TMath::ATan(uy2)-TMath::ATan(uy1));
+}
+//__________________________________________________________________________________________________
+void AliRICHParam::Loc2Area(TVector2 x2,Int_t &iPadXmin,Int_t &iPadYmin,Int_t &iPadXmax,Int_t &iPadYmax)
+{
+// Calculates the area of disintegration for a given point. It's assumed here that this points lays on anode wire.
+// Area is a rectangulare set of pads defined by its left-down and right-up coners.
+ Loc2Pad(x2-MathiesonDelta(),iPadXmin,iPadYmin);
+ Loc2Pad(x2+MathiesonDelta(),iPadXmax,iPadYmax);
+}
+//__________________________________________________________________________________________________
+Bool_t AliRICHParam::IsOverTh(Int_t c,Int_t x,Int_t y,Double_t q)
+{
+// Calculate the new charge subtracting pedestal and if the current digit is over threshold
+ if (c>0 && x>0 && y>0 && c<kNCH && x<kNpadsX && y<kNpadsY)
+ if(q>NsigmaTh()*fSigmaThMap[c-1][x-1][y-1]) return kTRUE;
+ return kFALSE;
+}
+//__________________________________________________________________________________________________
+TVector2 AliRICHParam::ShiftToWirePos(TVector2 x2)
+{
+// Calculate the position of the wire nearest to the hit
+ Int_t padx,pady;
+ Loc2Pad(x2,padx,pady);
+ Double_t x;
+ TVector2 center2=Pad2Loc(padx,pady);
+ if(x2.X()>center2.X()) x=center2.X()+0.5*WirePitch();
+ else x=center2.X()-0.5*WirePitch();
+ x2.Set(x,x2.Y());
+ return x2;
+}
#endif //AliRICHParam_h