1 /**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
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 **************************************************************************/
18 Revision 1.2 2000/07/10 16:07:19 fca
19 Release version of ITS code
23 #include <TParticle.h>
27 #include "AliITShit.h"
28 #include "AliITSRecPoint.h"
29 #include "AliITSmodule.h"
30 #include "AliITSgeom.h"
31 #include "AliITSsimulationFastPointsV0.h"
32 #include "AliITSstatistics.h"
34 ClassImp(AliITSsimulationFastPointsV0)
36 AliITSsimulationFastPointsV0::AliITSsimulationFastPointsV0()
39 fSx = new AliITSstatistics(2);
40 fSz = new AliITSstatistics(2);
43 //----------------------------------------------------------
44 AliITSsimulationFastPointsV0::~AliITSsimulationFastPointsV0()
52 //-------------------------------------------------------------
53 void AliITSsimulationFastPointsV0::CreateFastRecPoints(AliITSmodule *mod,Int_t module,TRandom *rndm){
54 // Fast points simulator for all of the ITS.
55 Int_t nhit,h,trk,ifirst;
56 Float_t x,y,z,t,e;// local coordinate (cm) and time of flight, and dedx.
60 fSx->Reset(); // Start out with things clearly zeroed
61 fSz->Reset(); // Start out with things clearly zeroed
62 e = 0.; // Start out with things clearly zeroed
64 nhit = mod->GetNhits();
68 hit->GetPositionL(x,y,z,t);
69 if(ifirst) {x1=x;y1=y;z1=z;}
70 e += hit->GetIonization();
71 trk = hit->GetTrack();
72 fSx->AddValue((Double_t)x,weight);
73 fSz->AddValue((Double_t)z,weight);
75 if(hit->StatusExiting()|| // leaving volume
76 hit->StatusDisappeared()|| // interacted/decayed...
77 hit->StatusStop() // dropped below E cuts.
78 ){ // exiting track, write out RecPoint.
79 // if(fSz->GetRMS()>1.E-1) {
80 // TParticle *part = hit->GetParticle();
81 // printf("idpart %d energy %f \n",part->GetPdgCode(),part->Energy());
82 // printf("diffx=%e diffy=%e diffz=%e\n",x-x1,y-y1,z-z1);
84 switch (mod->GetLayer()){
85 case 1: case 2: // SPDs
88 case 3: case 4: // SDDs
91 case 5: case 6: // SSDs
103 //_______________________________________________________________________
104 void AliITSsimulationFastPointsV0::AddSPD(Float_t &e,
105 AliITSmodule *mod,Int_t trackNumber){
106 const Float_t kmicronTocm = 1.0e-4;
107 // const Float_t kdEdXtoQ = ;
108 const Float_t kRMSx = 12.0*kmicronTocm; // microns->cm ITS TDR Table 1.3
109 const Float_t kRMSz = 70.0*kmicronTocm; // microns->cm ITS TDR Table 1.3
110 Float_t a1,a2; // general float.
111 AliITSRecPoint rpSPD;
113 rpSPD.fTracks[0]=trackNumber;
116 rpSPD.SetX(fSx->GetMean());
117 rpSPD.SetZ(fSz->GetMean());
120 a1 = fSx->GetRMS(); a1 *= a1; a1 += kRMSx*kRMSx;
121 // if(a1>1.E5) printf("addSPD: layer=%d track #%d dedx=%e sigmaX2= %e ",
122 // mod->GetLayer(),trackNumber,e,a1);
123 rpSPD.SetSigmaX2(a1);
124 a2 = fSz->GetRMS(); a2 *= a2; a2 += kRMSz*kRMSz;
125 // if(a1>1.E5) printf(" sigmaZ2= %e\n",a2);
126 rpSPD.SetSigmaZ2(a2);
128 (mod->GetITS())->AddRecPoint(rpSPD);
130 //_______________________________________________________________________
131 void AliITSsimulationFastPointsV0::AddSDD(Float_t &e,
132 AliITSmodule *mod,Int_t trackNumber){
134 const Float_t kmicronTocm = 1.0e-4;
135 const Float_t kdEdXtoQ = 2.778e+8;
136 const Float_t kRMSx = 38.0*kmicronTocm; // microns->cm ITS TDR Table 1.3
137 const Float_t kRMSz = 28.0*kmicronTocm; // microns->cm ITS TDR Table 1.3
138 Float_t a1,a2; // general float.
139 AliITSRecPoint rpSDD;
141 rpSDD.fTracks[0]=trackNumber;
144 rpSDD.SetX(fSx->GetMean());
145 rpSDD.SetZ(fSz->GetMean());
147 rpSDD.SetQ(kdEdXtoQ*e);
148 a1 = fSx->GetRMS(); a1 *= a1; a1 += kRMSx*kRMSx;
149 // if(a1>1.E5) printf("addSDD: layer=%d track #%d dedx=%e sigmaX2= %e ",
150 // mod->GetLayer(),trackNumber,e,a1);
151 rpSDD.SetSigmaX2(a1);
152 a2 = fSz->GetRMS(); a2 *= a2; a2 += kRMSz*kRMSz;
153 // if(a1>1.E5) printf(" sigmaZ2= %e\n",a2);
154 rpSDD.SetSigmaZ2(a2);
156 (mod->GetITS())->AddRecPoint(rpSDD);
158 //_______________________________________________________________________
159 void AliITSsimulationFastPointsV0::AddSSD(Float_t &e,
160 AliITSmodule *mod,Int_t trackNumber){
162 const Float_t kmicronTocm = 1.0e-4;
163 const Float_t kdEdXtoQ = 2.778e+8;
164 const Float_t kRMSx = 20.0*kmicronTocm; // microns->cm ITS TDR Table 1.3
165 const Float_t kRMSz = 830.0*kmicronTocm; // microns->cm ITS TDR Table 1.3
166 Float_t a1,a2; // general float.
167 AliITSRecPoint rpSSD;
169 rpSSD.fTracks[0]=trackNumber;
172 rpSSD.SetX(fSx->GetMean());
173 rpSSD.SetZ(fSz->GetMean());
175 rpSSD.SetQ(kdEdXtoQ*e);
176 a1 = fSx->GetRMS(); a1 *= a1; a1 += kRMSx*kRMSx;
177 // if(a1>1.E5) printf("addSSD: layer=%d track #%d dedx=%e sigmaX2= %e ",
178 // mod->GetLayer(),trackNumber,e,a1);
179 rpSSD.SetSigmaX2(a1);
180 a2 = fSz->GetRMS(); a2 *= a2; a2 += kRMSz*kRMSz;
181 // if(a1>1.E5) printf(" sigmaZ2= %e RMSx=%e RMSz=%e\n",a2,fSx->GetRMS(),fSz->GetRMS());
182 rpSSD.SetSigmaZ2(a2);
184 (mod->GetITS())->AddRecPoint(rpSSD);
186 //_______________________________________________________________________