RICH/AliRICHParam.cxx

   1 //  **************************************************************************
   2 //  * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
   3 //  *                                                                        *
   4 //  * Author: The ALICE Off-line Project.                                    *
   5 //  * Contributors are mentioned in the code where appropriate.              *
   6 //  *                                                                        *
   7 //  * Permission to use, copy, modify and distribute this software and its   *
   8 //  * documentation strictly for non-commercial purposes is hereby granted   *
   9 //  * without fee, provided that the above copyright notice appears in all   *
  10 //  * copies and that both the copyright notice and this permission notice   *
  11 //  * appear in the supporting documentation. The authors make no claims     *
  12 //  * about the suitability of this software for any purpose. It is          *
  13 //  * provided "as is" without express or implied warranty.                  *
  14 //  **************************************************************************
  15 #include "AliRICHParam.h"
  16 #include "AliESD.h"
  17 #include "AliRICHChamber.h"
  18 #include <TCanvas.h>
  19 #include <TLatex.h>
  20 #include <THStack.h>
  21 #include <TLegend.h>
  22 #include <TView.h>
  23 #include <TPolyMarker3D.h>
  24 #include <TPolyLine3D.h>
  25 #include <TPolyLine.h>
  26 #include <TSystem.h>
  27 #include <TVector2.h>
  28 #include <TVector3.h>
  29 #include <TRotation.h>
  30
  31
  32 ClassImp(AliRICHParam)
  33 Bool_t   AliRICHParam::fgIsWireSag            =kTRUE;   //take ware sagita into account?
  34 Bool_t   AliRICHParam::fgIsResolveClusters    =kTRUE;   //do cluster resolving?
  35 Bool_t   AliRICHParam::fgIsFeedback           =kTRUE;   //generate feedback photons?
  36 Bool_t   AliRICHParam::fgIsRadioSrc           =kFALSE;  //put radioactive source instead of radiators?
  37 Bool_t   AliRICHParam::fgIsAerogel            =kFALSE;  //special aerogel configuration
  38 Bool_t   AliRICHParam::fgIsTestBeam           =kFALSE;  //special test beam configuration
  39
  40 Int_t    AliRICHParam::fgHV[kNsectors]        ={2050,2050,2050,2050,2050,2050};
  41 Int_t    AliRICHParam::fgNsigmaTh             =4;
  42 Float_t  AliRICHParam::fgSigmaThMean          =1.132; //QDC
  43 Float_t  AliRICHParam::fgSigmaThSpread        =0.035; //
  44 Double_t AliRICHParam::fgErrChrom[4][330];                       //
  45 Double_t AliRICHParam::fgErrGeom[4][330];                        //
  46 Double_t AliRICHParam::fgErrLoc[4][330];                         //Chromatic, Geometric and Localization array to parametrize SigmaCerenkov
  47
  48
  49 //__________________________________________________________________________________________________
  50 void AliRICHParam::Print(Option_t*) const
  51 {
  52 //print some usefull (hopefully) info on some internal guts of RICH parametrisation
  53   AliInfo(Form("Pads in chamber (%3i,%3i) in sector (%2i,%2i) pad size (%4.2f,%4.2f)",NpadsX(),NpadsY(),NpadsXsec(),NpadsYsec(),PadSizeX(),PadSizeY()));
  54   AliInfo(Form("Resolve clusters %i sagita %i Radio source %i Aerogel %i TestBeam %i",
  55                 IsResolveClusters(),IsWireSag(),IsRadioSrc(),IsAerogel(),IsTestBeam()));
  56   fpChambers->Print();
  57 }//Print()
  58 //__________________________________________________________________________________________________
  59 void AliRICHParam::CreateChambers()
  60 {
  61 //Create all RICH Chambers on each call. Previous chambers deleted.
  62   if(fpChambers) delete fpChambers;
  63   if(fgIsTestBeam){
  64     fpChambers=new TObjArray(1);//test beam configuration 1 chamber
  65     fpChambers->AddAt(new AliRICHChamber(0),0);
  66   }else{
  67     fpChambers=new TObjArray(kNchambers);//normal configuration 7 chambers
  68     for(int iChamberN=0;iChamberN<kNchambers;iChamberN++)  fpChambers->AddAt(new AliRICHChamber(iChamberN+1),iChamberN);
  69   }
  70   fpChambers->SetOwner();
  71 }//CreateChambers()
  72 //__________________________________________________________________________________________________
  73 Float_t AliRICHParam::AbsCH4(Float_t eV)
  74 {
  75 //Evaluate the absorbtion lenght of CH4 for a photon of energy eV in electron-volts
  76   const Float_t kLoschmidt=2.686763e19;                                      // LOSCHMIDT NUMBER IN CM-3
  77   const Float_t kPressure=750.0;          //mm of Hg
  78   const Float_t kTemperature=283.0;       //K (10 grad C)
  79   const Float_t kPn=kPressure/760.;
  80   const Float_t kTn=kTemperature/273.16;
  81   const Float_t kC0=-1.655279e-1;
  82   const Float_t kC1= 6.307392e-2;
  83   const Float_t kC2=-8.011441e-3;
  84   const Float_t kC3= 3.392126e-4;
  85
  86   Float_t crossSection=0;
  87   if (eV<7.75)
  88     crossSection=0.06e-22;
  89   else                 //------ METHANE CROSS SECTION cm-2 ASTROPH. J. 214, L47 (1978)
  90     crossSection=(kC0+kC1*eV+kC2*eV*eV+kC3*eV*eV*eV)*1.e-18;
  91
  92     Float_t density=kLoschmidt*kPn/kTn; //CH4 molecular concentration (cm^-3)
  93     return 1.0/(density*crossSection);
  94 }//AbsoCH4()
  95 //__________________________________________________________________________________________________
  96 void AliRICHParam::TestSeg()
  97 {
  98 //Provides a set of pictures to test segementation currently in use.
  99   new TCanvas("pads","PC segmentation - pads display",700,600);
 100   gPad->Range(-5,-5,PcSizeX()+5,PcSizeY()+15);
 101   TVector p(2);   TVector2 c;    TVector2 b;   //current: pad, pad center, pad boundary
 102 // list of corners:
 103   Double_t x0=0,x1=SectorSizeX(),x2=SectorSizeX()+DeadZone(),                                                                 x3=PcSizeX();
 104   Double_t y0=0,y1=SectorSizeY(),y2=SectorSizeY()+DeadZone(),y3=2*SectorSizeY()+DeadZone(),y4=PcSizeY()-SectorSizeY(),y5=PcSizeY();
 105   DrawSectors();
 106 //header
 107   TLatex t;
 108   t.SetTextSize(0.02); t.SetTextColor(kBlack); t.SetTextAlign(11);
 109   t.DrawLatex(0,PcSizeY()+10,Form("IP in front of this page. pad size %.2fx%.2fcm   dead zone %.2fcm",PadSizeX(),PadSizeY(),DeadZone()));
 110   t.DrawLatex(0,PcSizeY()+ 5,Form("Pc  %.2fx%.2f cm %ix%i pads               Sec %.2fx%.2f cm %ix%i pads",
 111                                          PcSizeX()     , PcSizeY()     , NpadsX()    , NpadsY()                                 ,
 112                                          SectorSizeX() , SectorSizeY() , NpadsXsec() , NpadsYsec()                              ));
 113 //sectors
 114   t.SetTextSize(0.015); t.SetTextColor(kRed); t.SetTextAlign(22);
 115   c=Pad2Loc( 40, 24); t.DrawText(c.X(),c.Y(),Form("sec 1 (%.2f,%.2f)",c.X(),c.Y()  ));
 116   c=Pad2Loc( 40, 75); t.DrawText(c.X(),c.Y(),Form("sec 3 (%.2f,%.2f)",c.X(),c.Y()  ));
 117   c=Pad2Loc( 40,121); t.DrawText(c.X(),c.Y(),Form("sec 5 (%.2f,%.2f)",c.X(),c.Y()  ));
 118   c=Pad2Loc(120, 24); t.DrawText(c.X(),c.Y(),Form("sec 2 (%.2f,%.2f)",c.X(),c.Y()  ));
 119   c=Pad2Loc(120, 75); t.DrawText(c.X(),c.Y(),Form("sec 4 (%.2f,%.2f)",c.X(),c.Y()  ));
 120   c=Pad2Loc(120,121); t.DrawText(c.X(),c.Y(),Form("sec 6 (%.2f,%.2f)",c.X(),c.Y()  ));
 121 //coners
 122   t.SetTextSize(0.015); t.SetTextColor(kBlue);
 123
 124   b.Set(x0,y0);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(11);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 125   b.Set(x0,y1);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(13);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 126   b.Set(x0,y2);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(11);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 127   b.Set(x0,y3);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(13);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 128   b.Set(x0,y4);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(11);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 129   b.Set(x0,y5);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(13);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 130
 131   b.Set(x1,y0);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(31);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 132   b.Set(x1,y1);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(33);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 133   b.Set(x1,y2);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(31);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 134   b.Set(x1,y3);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(33);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 135   b.Set(x1,y4);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(31);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 136   b.Set(x1,y5);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(33);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 137
 138   b.Set(x2,y0);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(11);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 139   b.Set(x2,y1);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(13);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 140   b.Set(x2,y2);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(11);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 141   b.Set(x2,y3);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(13);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 142   b.Set(x2,y4);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(11);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 143   b.Set(x2,y5);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(13);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 144
 145   b.Set(x3,y0);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(31);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 146   b.Set(x3,y1);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(33);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 147   b.Set(x3,y2);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(31);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 148   b.Set(x3,y3);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(33);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 149   b.Set(x3,y4);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(31);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 150   b.Set(x3,y5);p=Loc2Pad(b);c=Pad2Loc(p);t.SetTextAlign(33);t.DrawText(c.X(),c.Y(),Form("(%.2f,%.2f)-(%.0f,%.0f)-(%.2f,%.2f)",b.X(),b.Y(),p(0),p(1),c.X(),c.Y()));
 151 }//TestSeg()
 152 //__________________________________________________________________________________________________
 153 void AliRICHParam::TestResp()
 154 {
 155 //Provides a set of plot to check the response parametrisation currently in use.
 156   TCanvas *pC=new TCanvas("c","Amplification test",900,800);
 157   pC->Divide(1,2);
 158
 159
 160   const Int_t kNpoints=8;
 161   THStack *pStackPhot=new THStack("StackPhot","photons");
 162   THStack *pStackMip =new THStack("StackMip","mips");
 163   TLegend *pLeg=new TLegend(0.6,0.2,0.9,0.5,"legend");
 164   TH1F *apHphot[kNpoints];
 165   TH1F *apHmip[kNpoints];
 166
 167   Double_t starty=0;
 168   Double_t deltay=AliRICHParam::SectorSizeY()/kNpoints;
 169
 170   for(int i=0;i<kNpoints;i++){
 171     apHphot[i]=new TH1F(Form("hphot%i",i),"Qdc for Photon;QDC;Counts",500,0,500); apHphot[i]->SetLineColor(i);pStackPhot->Add(apHphot[i]);
 172     apHmip[i] =new TH1F(Form("hmip%i",i),"Qdc for Mip;QDC;Counts",4000,0,4000);   apHmip[i]->SetLineColor(i);pStackMip->Add(apHmip[i]);
 173
 174     pLeg->AddEntry(apHphot[i],Form("@(10,%5.2f->%5.2f)",starty+i*deltay,starty+i*deltay-SectorSizeY()/2));
 175   }
 176
 177
 178   TVector2 x2(0,0);
 179   for(Int_t i=0;i<10000;i++){//events loop
 180     for(int j=0;j<kNpoints;j++){
 181       x2.Set(10,starty+j*deltay);
 182       apHphot[j]->Fill(TotQdc(x2,0));
 183       apHmip[j]->Fill(TotQdc(x2,gRandom->Landau(600,150)*1e-9));
 184     }
 185   }
 186
 187   pC->cd(1);  pStackMip->Draw("nostack");
 188   pC->cd(2);  pStackPhot->Draw("nostack"); pLeg->Draw();
 189 }//TestResp()
 190 //__________________________________________________________________________________________________
 191 void AliRICHParam::TestTrans()
 192 {
 193 //Provides a set of plots to test transformation methods
 194   new TCanvas("trasform","Test LRS-MRS transform");
 195   TLatex t; t.SetTextSize(0.02);
 196
 197   TView *pView=new TView(1);
 198   pView->SetRange(-600,-600,-600,600,600,600);
 199   DrawAxis();
 200 //Draw PC for all chambers by trasfering Pc plane using Pc2Mrs methode
 201   Int_t iNpointsX=50,iNpointsY=50;
 202   for(Int_t iChamberN=1;iChamberN<=7;iChamberN++){//chamber loop
 203     TPolyMarker3D *pChamber=new TPolyMarker3D(iNpointsX*iNpointsY);
 204     Int_t i=0;
 205     for(Double_t x=0;x<PcSizeX();x+=PcSizeX()/iNpointsX)
 206       for(Double_t y=0;y<PcSizeY();y+=PcSizeY()/iNpointsY){//step loop
 207         TVector3 v3=C(iChamberN)->Pc2Mrs(TVector2(x,y));//from regular grid of local PC points to MRS presentation
 208         pChamber->SetPoint(i++,v3.X(),v3.Y(),v3.Z());//Pc plane poing in MRS
 209       }//step loop
 210     pChamber->SetMarkerSize(1);
 211     pChamber->SetMarkerColor(iChamberN);
 212     pChamber->Draw();
 213     t.SetNDC();t.SetTextColor(iChamberN); t.DrawText(0.1,iChamberN*0.1,Form("Chamber %i",iChamberN));
 214   }//chamber loop
 215 //  gPad->GetView()->RotateView(94,45);
 216 }//TestTrans()
 217 //__________________________________________________________________________________________________
 218 void AliRICHParam::DrawAxis()
 219 {
 220 //Utility: draws axis on geometry scene
 221   Double_t x[6]={0,0,0,300,0,0};  Double_t y[6]={0,0,0,0,300,0};  Double_t z[6]={0,0,0,0,0,300};
 222   TPolyLine3D *pXaxis=new TPolyLine3D(2,x);pXaxis->SetLineColor(kRed);   pXaxis->Draw();
 223   TPolyLine3D *pYaxis=new TPolyLine3D(2,y);pYaxis->SetLineColor(kGreen); pYaxis->Draw();
 224   TPolyLine3D *pZaxis=new TPolyLine3D(2,z);pZaxis->SetLineColor(kBlue);  pZaxis->Draw();
 225 }
 226 //__________________________________________________________________________________________________
 227 void AliRICHParam::DrawSectors()
 228 {
 229 //Utility: draws RICH chamber sectors on event display.
 230   Double_t xLeft[5]  = {0,0,SectorSizeX(),SectorSizeX(),0};
 231   Double_t xRight[5] = {SectorSizeX()+DeadZone(),SectorSizeX()+DeadZone(),PcSizeX(),PcSizeX(),SectorSizeX()+DeadZone()};
 232
 233   Double_t yDown[5]   = {0,SectorSizeY(),SectorSizeY(),0,0};
 234   Double_t yCenter[5] = {  SectorSizeY()+DeadZone(),2*SectorSizeY()+DeadZone(),2*SectorSizeY()+DeadZone(),
 235                            SectorSizeY()+DeadZone(),SectorSizeY()+DeadZone()};
 236   Double_t yUp[5]     = {2*SectorSizeY()+2*DeadZone(),PcSizeY(),PcSizeY(),2*SectorSizeY()+2*DeadZone(),2*SectorSizeY()+2*DeadZone()};
 237
 238   TPolyLine *sec1 = new TPolyLine(5,xLeft ,yDown);    sec1->SetLineColor(21);  sec1->Draw();
 239   TPolyLine *sec2 = new TPolyLine(5,xRight,yDown);    sec2->SetLineColor(21);  sec2->Draw();
 240   TPolyLine *sec3 = new TPolyLine(5,xLeft ,yCenter);  sec3->SetLineColor(21);  sec3->Draw();
 241   TPolyLine *sec4 = new TPolyLine(5,xRight,yCenter);  sec4->SetLineColor(21);  sec4->Draw();
 242   TPolyLine *sec5 = new TPolyLine(5,xLeft, yUp);      sec5->SetLineColor(21);  sec5->Draw();
 243   TPolyLine *sec6 = new TPolyLine(5,xRight,yUp);      sec6->SetLineColor(21);  sec6->Draw();
 244 }//DrawSectors()
 245 //__________________________________________________________________________________________________
 246 void AliRICHParam::ReadErrFiles()
 247 {
 248 // Read the three files corresponding to Chrom,Geom and Loc
 249 // They are parameters of a polynomial of 6th order...
 250
 251   static Bool_t count = kFALSE;
 252
 253   Float_t c0,c1,c2,c3,c;
 254   Float_t g0,g1,g2,g3,g;
 255   Float_t l0,l1,l2,l3,l;
 256
 257   FILE *pChromErr, *pGeomErr, *pLocErr;
 258
 259   if(!count) {
 260      AliInfoGeneral("ReadErrFiles","reading RICH error parameters...");
 261      pChromErr = fopen(Form("%s/RICH/RICHConfig/SigmaChromErr.txt",gSystem->Getenv("ALICE_ROOT")),"r");
 262      pGeomErr  = fopen(Form("%s/RICH/RICHConfig/SigmaGeomErr.txt",gSystem->Getenv("ALICE_ROOT")),"r");
 263      pLocErr   = fopen(Form("%s/RICH/RICHConfig/SigmaLocErr.txt",gSystem->Getenv("ALICE_ROOT")),"r");
 264      if(!pChromErr||!pGeomErr||!pLocErr) {AliErrorGeneral("ReadErrFiles"," RICH ERROR READING Parameter FILES: can't open files!!! ");return;}
 265      for(Int_t i=0;i<330;i++) {
 266        fscanf(pChromErr,"%f%f%f%f%f\n",&c0,&c1,&c2,&c3,&c);
 267        fscanf(pGeomErr,"%f%f%f%f%f\n",&g0,&g1,&g2,&g3,&g);
 268        fscanf(pLocErr,"%f%f%f%f%f\n",&l0,&l1,&l2,&l3,&l);
 269        fgErrChrom[0][i] = c0;
 270        fgErrChrom[1][i] = c1;
 271        fgErrChrom[2][i] = c2;
 272        fgErrChrom[3][i] = c3;
 273        fgErrGeom[0][i] = g0;
 274        fgErrGeom[1][i] = g1;
 275        fgErrGeom[2][i] = g2;
 276        fgErrGeom[3][i] = g3;
 277        fgErrLoc[0][i] = l0;
 278        fgErrLoc[1][i] = l1;
 279        fgErrLoc[2][i] = l2;
 280        fgErrLoc[3][i] = l3;
 281      }
 282      AliInfoGeneral("ReadErrFiles","DONE successfully!");
 283      fclose(pChromErr);
 284      fclose(pGeomErr);
 285      fclose(pLocErr);
 286   }
 287   count = kTRUE;
 288 }//ReadErrFiles()
 289 //__________________________________________________________________________________________________
 290 TVector3 AliRICHParam::SigmaSinglePhoton(Int_t partID, Double_t mom, Double_t theta, Double_t phi)
 291
 292 {
 293 // Find sigma for single photon. It returns the thrree different errors. If you want
 294 // to have the error---> TVector3.Mag()
 295
 296   TVector3 v(-999,-999,-999);
 297   Double_t pmom;
 298
 299   ReadErrFiles();
 300   Double_t mass = AliPID::ParticleMass(partID);
 301   Double_t massRef = AliPID::ParticleMass(AliPID::kProton); // all the files are calculated for protons...so mass ref is proton mass
 302   pmom = mom*massRef/mass; // normalized momentum respect to proton...
 303   if(pmom>6.5) pmom = 6.5;
 304   Double_t oneOverRefIndex = 1/RefIdxC6F14(6.755);
 305   Double_t pmin = mass*oneOverRefIndex/TMath::Sqrt(1-oneOverRefIndex*oneOverRefIndex);
 306   if(pmom<pmin) return v;
 307   v.SetX(Interpolate(fgErrChrom,pmom,theta,phi));
 308   v.SetY(Interpolate(fgErrGeom,pmom,theta,phi));
 309   v.SetZ(Interpolate(fgErrLoc,pmom,theta,phi));
 310
 311   return v;
 312 }//SigmaSinglePhoton
 313 //__________________________________________________________________________________________________
 314 Double_t AliRICHParam::Interpolate(Double_t par[4][330], Double_t x, Double_t y, Double_t phi)
 315
 316 {
 317   static Double_t amin = 1.15; static Double_t astep  = 0.2;
 318   static Double_t bmin = 0; static Double_t bstep  = 1;
 319
 320   Double_t Phi = (phi - 180)/300.;
 321
 322   Double_t Sigma[30][11];
 323
 324   for(Int_t j=0;j<11;j++) { for(Int_t i=0;i<30;i++) {
 325     Sigma[i][j] = par[0][j+11*i] + par[1][j+11*i]*Phi*Phi + par[2][j+11*i]*TMath::Power(Phi,4) + par[3][j+11*i]*TMath::Power(Phi,6);
 326     }
 327   }
 328
 329   Int_t i=0;Int_t j=0;
 330
 331   i = (Int_t)((x-amin)/astep);
 332   j = (Int_t)((y-bmin)/bstep);
 333   Double_t ai = amin+i*astep;
 334   Double_t ai1 = ai+astep;
 335   Double_t bj = bmin+j*bstep;
 336   Double_t bj1 = bj+bstep;
 337   Double_t t = (x-ai)/(ai1-ai);
 338   Double_t gj = (1-t)*Sigma[i][j]+t*Sigma[i+1][j];
 339   Double_t gj1 = (1-t)*Sigma[i][j+1]+t*Sigma[i+1][j+1];
 340   Double_t u = (y-bj)/(bj1-bj);
 341   return (1-u)*gj+u*gj1;
 342 }//Interpolate
 343 //__________________________________________________________________________________________________
 344 TVector3 AliRICHParam::ForwardTracing(TVector3 entranceTrackPoint, TVector3 vectorTrack, Double_t thetaC, Double_t phiC)
 345 {
 346 //
 347   TVector3 vBad(-999,-999,-999);
 348   TVector3 nPlane(0,0,1);
 349   Double_t planeZposition = 0.5*Zfreon();
 350   TVector3 planePoint(0,0,planeZposition);
 351   TVector3 emissionPoint = PlaneIntersect(vectorTrack,entranceTrackPoint,nPlane,planePoint);
 352 //  emissionPoint.Dump();
 353   Double_t thetaout,phiout;
 354   AnglesInDRS(vectorTrack.Theta(),vectorTrack.Phi(),thetaC,phiC,thetaout,phiout);
 355 //  cout << "thetaout "<<thetaout << " phiout " << phiout << endl;
 356   TVector3 vectorPhotonInC6F14;
 357   vectorPhotonInC6F14.SetMagThetaPhi(1,thetaout,phiout);
 358 //  vectorPhotonInC6F14.Dump();
 359 //  planeZposition=AliRICHParam::C6F14Thickness();
 360   planeZposition=Zfreon();
 361   planePoint.SetXYZ(0,0,planeZposition);
 362   TVector3 entranceToSiO2Point = PlaneIntersect(vectorPhotonInC6F14,emissionPoint,nPlane,planePoint);
 363 //  entranceToSiO2Point.Dump();
 364
 365   Double_t photonEn = MeanCkovEnergy();
 366   Double_t angleInSiO2 = SnellAngle(RefIdxC6F14(photonEn),RefIdxSiO2(photonEn),vectorPhotonInC6F14.Theta());if(angleInSiO2<0) return vBad;
 367   TVector3 vectorPhotonInSiO2;
 368   vectorPhotonInSiO2.SetMagThetaPhi(1,angleInSiO2,phiout);
 369 //  planeZposition+=AliRICHParam::SiO2Thickness();
 370   planeZposition+=Zwin();
 371   planePoint.SetXYZ(0,0,planeZposition);
 372   TVector3 entranceToCH4 = PlaneIntersect(vectorPhotonInSiO2,entranceToSiO2Point,nPlane,planePoint);
 373 //  entranceToCH4.Dump();
 374
 375   //  Double_t angleInCH4 = SnellAngle(AliRICHParam::IndOfRefSiO2(6.755),AliRICHParam::IndOfRefCH4,angleInSiO2);
 376   Double_t angleInCH4 = SnellAngle(RefIdxSiO2(photonEn),RefIdxCH4(photonEn),vectorPhotonInSiO2.Theta());if(angleInCH4<0) return vBad;
 377   TVector3 vectorPhotonInCH4;
 378   vectorPhotonInCH4.SetMagThetaPhi(1,angleInCH4,phiout);
 379 //  planeZposition+=AliRICHParam::GapProx();
 380   planeZposition+=Pc2Win();
 381   planePoint.SetXYZ(0,0,planeZposition);
 382   TVector3 impactToPC = PlaneIntersect(vectorPhotonInCH4,entranceToCH4,nPlane,planePoint);
 383 //  impactToPC.Dump();
 384   return impactToPC;
 385 }//FowardTracing
 386 //__________________________________________________________________________________________________
 387 TVector3 AliRICHParam::PlaneIntersect(TVector3 vstart,TVector3 p0,TVector3 n,TVector3 v0)
 388 {
 389 //
 390   TVector3 parallel(-999,-999,-999);
 391   // vstart = given vector
 392   // p0 = origin of the given vector
 393   // n = normal to a given plane
 394   // v0 = point of the given plane
 395 //  cout << " n*vstart = " << n*vstart << endl;
 396   if(n*vstart==0) return parallel;
 397   TVector3 diff=v0-p0;
 398   Double_t sint=(n*diff)/(n*vstart);
 399   return p0+sint*vstart;
 400 }//PlaneIntersect
 401 //__________________________________________________________________________________________________
 402 Double_t AliRICHParam::SnellAngle(Float_t n1, Float_t n2, Float_t theta1)
 403 {
 404 // Snell law
 405 // Compute the Snell angle
 406
 407   Double_t sinrefractangle;
 408   Double_t refractangle;
 409
 410   sinrefractangle = (n1/n2)*sin(theta1);
 411
 412   if(sinrefractangle>1.) {
 413     //    cout << " PROBLEMS IN SNELL ANGLE !!!!! " << endl;
 414     refractangle = -999.;
 415     return refractangle;
 416   }
 417
 418   refractangle = asin(sinrefractangle);
 419   return refractangle;
 420 }//SnellAngle
 421 //__________________________________________________________________________________________________
 422 void AliRICHParam::AnglesInDRS(Double_t trackTheta,Double_t trackPhi,Double_t thetaCerenkov,Double_t phiCerenkov,Double_t &tout,Double_t &pout)
 423 {
 424 // Setup the rotation matrix of the track...
 425
 426   TRotation mtheta;
 427   TRotation mphi;
 428   TRotation minv;
 429   TRotation mrot;
 430
 431   mtheta.RotateY(trackTheta);
 432   mphi.RotateZ(trackPhi);
 433
 434   mrot = mphi * mtheta;
 435     //  minv = mrot.Inverse();
 436
 437   TVector3 photonInRadiator(1,1,1);
 438
 439   photonInRadiator.SetTheta(thetaCerenkov);
 440   photonInRadiator.SetPhi(phiCerenkov);
 441   photonInRadiator = mrot * photonInRadiator;
 442   tout=photonInRadiator.Theta();
 443   pout=photonInRadiator.Phi();
 444 }//AnglesInDRS
 445 //__________________________________________________________________________________________________
 446
 447 //__________________________________________________________________________________________________
 448 //__________________________________________________________________________________________________
 449 /*
 450 void DrawRing()
 451 {
 452
 453   //  Float_t xGraph[1000],yGraph[1000];
 454
 455   Float_t type;
 456   Float_t MassOfParticle;
 457   Float_t beta;
 458   Float_t nfreon;
 459
 460   Float_t ThetaCerenkov;
 461
 462   Float_t Xtoentr = GetEntranceX();
 463   Float_t Ytoentr = GetEntranceY();
 464
 465   Float_t pmod = GetTrackMomentum();
 466   Float_t TrackTheta = GetTrackTheta();
 467   Float_t TrackPhi = GetTrackPhi();
 468
 469   SetPhotonEnergy(AliRICHParam::MeanCkovEnergy());
 470   SetFreonRefractiveIndex();
 471
 472   SetEmissionPoint(RadiatorWidth/2.);
 473
 474   ThetaCerenkov = GetThetaCerenkov();
 475   FindBetaFromTheta(ThetaCerenkov);
 476   nfreon = GetFreonRefractiveIndex();
 477
 478   Int_t nPoints = 100;
 479
 480   Int_t nPointsToDraw = 0;
 481   for(Int_t i=0;i<nPoints;i++)
 482     {
 483       Float_t phpad = 2*TMath::Pi()*i/nPoints;
 484       SetThetaPhotonInTRS(thetacer);
 485       SetPhiPhotonInTRS(phpad);
 486       FindPhotonAnglesInDRS();
 487       Float_t Radius = FromEmissionToCathode();
 488       if (Radius == 999.) continue;
 489       xGraph[nPointsToDraw] = GetXPointOnCathode() + GetShiftX();
 490       yGraph[nPointsToDraw] = GetYPointOnCathode() + GetShiftY();
 491       nPointsToDraw++;
 492     }
 493   gra = new TGraph(nPointsToDraw,xGraph,yGraph);
 494   gra->Draw("AC");
 495 }
 496 //__________________________________________________________________________________________________
 497 */