-/**************************************************************************
- * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
- * *
- * Author: The ALICE Off-line Project. *
- * Contributors are mentioned in the code where appropriate. *
- * *
- * Permission to use, copy, modify and distribute this software and its *
- * documentation strictly for non-commercial purposes is hereby granted *
- * without fee, provided that the above copyright notice appears in all *
- * copies and that both the copyright notice and this permission notice *
- * appear in the supporting documentation. The authors make no claims *
- * about the suitability of this software for any purpose. It is *
- * provided "as is" without express or implied warranty. *
- **************************************************************************/
-
#include <stdio.h>
+#include <stdlib.h>
+#include <iostream.h>
#include <TObjArray.h>
+#include <TRandom.h>
+#include <TMath.h>
+#include "AliITSmodule.h"
+#include "AliITSMapA2.h"
#include "AliITSsegmentationSSD.h"
#include "AliITSresponseSSD.h"
#include "AliITSsimulationSSD.h"
-#include "AliITSdictSSD.h"
+//#include "AliITSdictSSD.h"
#include "AliITSdcsSSD.h"
#include "AliITS.h"
#include "AliRun.h"
-
+#include "AliITSgeom.h"
ClassImp(AliITSsimulationSSD);
-//------------------------------------------------------------
+////////////////////////////////////////////////////////////////////////
+// Version: 0
+// Written by Enrico Fragiacomo
+// July 2000
+//
+// AliITSsimulationSSD is the simulation of SSDs.
+
+//----------------------------------------------------------------------
AliITSsimulationSSD::AliITSsimulationSSD(AliITSsegmentation *seg,
AliITSresponse *resp){
- // Constructor
+ // Constructor
fSegmentation = seg;
fResponse = resp;
+ Float_t noise[2] = {0.,0.};
+ fResponse->GetNoiseParam(noise[0],noise[1]); // retrieves noise parameters
fDCS = new AliITSdcsSSD(seg,resp);
fNstrips = fSegmentation->Npx();
fPitch = fSegmentation->Dpx(0);
-
- fP = new TArrayF(fNstrips);
- fN = new TArrayF(fNstrips);
+ fMapA2 = new AliITSMapA2(fSegmentation);
- fTracksP = new AliITSdictSSD[fNstrips];
- fTracksN = new AliITSdictSSD[fNstrips];
-
- fSteps = 10; // still hard-wired - set in SetDetParam and get it via
+ fSteps = 100; // still hard-wired - set in SetDetParam and get it via
// fDCS together with the others eventually
-
-
- //printf("SSD ctor: fNstrips fPitch %d %f\n",fNstrips, fPitch);
}
-//___________________________________________________________________________
+//______________________________________________________________________
AliITSsimulationSSD& AliITSsimulationSSD::operator=(AliITSsimulationSSD
&source){
-// Operator =
+ // Operator =
+
if(this==&source) return *this;
- this->fDCS = new AliITSdcsSSD(*(source.fDCS));
- this->fN = new TArrayF(*(source.fN));
- this->fP = new TArrayF(*(source.fP));
- this->fTracksP = new AliITSdictSSD(*(source.fTracksP));
- this->fTracksN = new AliITSdictSSD(*(source.fTracksN));
+ this->fDCS = new AliITSdcsSSD(*(source.fDCS));
+ this->fMapA2 = source.fMapA2;
this->fNstrips = source.fNstrips;
this->fPitch = source.fPitch;
this->fSteps = source.fSteps;
return *this;
}
-//_____________________________________________________________
+//_____________________________________________________________---------
AliITSsimulationSSD::AliITSsimulationSSD(AliITSsimulationSSD &source){
- // copy constructor
- *this = source;
+ // copy constructor
+
+ *this = source;
}
-//____________________________________________________________________________
+//______________________________________________________________________
AliITSsimulationSSD::~AliITSsimulationSSD() {
- // anihilator
-
- if(fP) delete fP;
- if(fN) delete fN;
-
- if(fTracksP) delete fTracksP;
- if(fTracksN) delete fTracksN;
-
+ // destructor
+ delete fMapA2;
delete fDCS;
-}
-//_______________________________________________________________
-//
-// Hit to digit
-//_______________________________________________________________
-//
+}
+//_______________________________________________________________-------
void AliITSsimulationSSD::DigitiseModule(AliITSmodule *mod,Int_t module,
Int_t dummy) {
- // Digitizes one SSD module of hits.
-
+ // Digitizes hits for one SSD module
+
+ Int_t lay, lad, detect;
+ AliITS *aliITS = (AliITS*)gAlice->GetModule("ITS");
+ AliITSgeom *geom = aliITS->GetITSgeom();
+ geom->GetModuleId(module,lay, lad, detect);
+ if ( lay == 6 )((AliITSsegmentationSSD*)fSegmentation)->SetLayer(6);
+ if ( lay == 5 )((AliITSsegmentationSSD*)fSegmentation)->SetLayer(5);
+
TObjArray *hits = mod->GetHits();
Int_t nhits = hits->GetEntriesFast();
- //printf("SSD: nhits %d\n",nhits);
if (!nhits) return;
-
- Int_t i;
- for(i=0; i<fNstrips; i++) {
- (*fP)[i] = 0;
- (*fN)[i] = 0;
- fTracksP[i].ZeroTracks();
- fTracksN[i].ZeroTracks();
- }
-
- for(i=0; i<nhits; i++) {
- Int_t idtrack=mod->GetHitTrackIndex(i);
- HitToDigit(i,idtrack,nhits,hits);
- }
-
-
- ApplyNoise();
- ApplyCoupling();
- ApplyThreshold();
- ApplyDAQ();
-
-
-}
-
-//---------------------------------------------------------------
-
-void AliITSsimulationSSD::HitToDigit(Int_t & hitNo,Int_t idtrack,
- Int_t nhits,TObjArray *hits) {
- // Turns one or more hits in an SSD module into one or more digits.
-
- Int_t stripP, stripN, i;
- Float_t dsP, dsN;
- Float_t sP, sN;
- Float_t eP, eN;
- Float_t arrayEP[10];
- Float_t arrayEN[10];
- Int_t track = 0;
-
- Float_t ionization = 0;
- Float_t signal;
-
- AliITSdictSSD *dict;
+ //cout<<"!! module, nhits ="<<module<<","<<nhits<<endl;
+
+ Double_t x0=0.0, y0=0.0, z0=0.0;
+ Double_t x1=0.0, y1=0.0, z1=0.0;
+ Double_t de=0.0;
+ Int_t maxNdigits = 2*fNstrips;
+ Float_t **pList = new Float_t* [maxNdigits];
+ memset(pList,0,sizeof(Float_t*)*maxNdigits);
+ Int_t indexRange[4] = {0,0,0,0};
+ static Bool_t first=kTRUE;
+ Int_t lasttrack = -2;
+ Int_t idtrack = -2;
-
- // check if this is the right order !!!!!
-
- AliITShit *hitI = (AliITShit*)hits->At(hitNo++);
- AliITShit *hitE = (AliITShit*)hits->At(hitNo);
+ for(Int_t i=0; i<nhits; i++) {
+ // LineSegmentL returns 0 if the hit is entering
+ // If hits is exiting returns positions of entering and exiting hits
+ // Returns also energy loss
-
- while (!((hitE->StatusExiting()) ||
- (hitE->StatusDisappeared()) ||
- (hitE->StatusStop()))) {
-
- if (++hitNo<nhits) {
- ionization = hitE->GetIonization();
- hitE = (AliITShit*)hits->At(hitNo);
- }
- }
-
-
- if (hitI->GetTrack() == hitE->GetTrack())
- //track = idtrack;
- track = hitI->GetTrack();
- else
- printf("!!! Emergency !!!\n");
-
-
- ionization += hitE->GetIonization();
+ if (mod->LineSegmentL(i, x0, x1, y0, y1, z0, z1, de, idtrack)) {
+ HitToDigit(module, x0, y0, z0, x1, y1, z1, de, indexRange, first);
- const Float_t kconvm=10000.; // cm -> microns
-
- Float_t xI, yI, zI;
- hitI->GetPositionL(xI, yI, zI);
-
- //Float_t zI = hitI->GetZL();
-
- xI *= kconvm;
- yI *= kconvm;
- zI *= kconvm;
-
- Float_t xE, yE, zE;
- hitE->GetPositionL(xE, yE, zE);
-
- //Float_t zE = hitE->GetZL();
+ if (lasttrack != idtrack || i==(nhits-1)) {
+ GetList(idtrack,pList,indexRange);
+ first=kTRUE;
+ } // end if
+ lasttrack=idtrack;
+ } // end if
+ } // end loop over hits
- xE *= kconvm;
- yE *= kconvm;
- zE *= kconvm;
-
- Float_t dx = (xE - xI);
- Float_t dz = (zE - zI);
-
-
- // Debuging
- /*
- fSegmentation->GetCellIxz(xI,zI,stripP,stripN);
-
- printf("%5d %8.3f %8.3f %8.3f %8.3f %d %d %d\n",
- hitNo, xI, zI, dx, dz,
- stripP, stripN, track);
- printf("%10.5f %10d \n", ionization, hitI->fTrack);
- */
-
- // end of debuging
-
-
- eP=0;
- eN=0;
- //fNparticles++;
-
- for(i=0; i<fSteps; i++) {
-
- // arrayEP[i] = gRandom->Landau(ionization/fSteps, ionization/(4*fSteps));
- // arrayEN[i] = gRandom->Landau(ionization/fSteps, ionization/(4*fSteps));
- arrayEP[i] = ionization/fSteps;
- arrayEN[i] = ionization/fSteps;
-
- eP += arrayEP[i];
- eN += arrayEN[i];
- }
-
- const Float_t kconv = 1.0e9 / 3.6; // GeV -> e-hole pairs
-
- for(i=0; i<fSteps; i++) {
-
- arrayEP[i] = kconv * arrayEP[i] * (ionization / eP);
- arrayEN[i] = kconv * arrayEN[i] * (ionization / eN);
- }
-
- dx /= fSteps;
- dz /= fSteps;
-
- Float_t sigmaP, sigmaN;
- fResponse->SigmaSpread(sigmaP,sigmaN);
-
- //printf("SigmaP SigmaN %f %f\n",sigmaP, sigmaN);
-
- Float_t noiseP, noiseN;
- fResponse->GetNoiseParam(noiseP,noiseN);
+ ApplyNoise();
+ ApplyCoupling();
- //printf("NoiseP NoiseN %f %f\n",noiseP, noiseN);
+ ChargeToSignal(pList);
- for(i=0; i<fSteps; i++) {
-
- Int_t j;
-
- fSegmentation->GetCellIxz(xI,zI,stripP,stripN);
- //printf("i xI zI stripP stripN %d %f %f %d %d\n",i,xI, zI, stripP, stripN);
- dsP = Get2Strip(1,stripP,xI, zI); // Between 0-1
- dsN = Get2Strip(0,stripN,xI, zI); // Between 0-1
-
- sP = sigmaP * sqrt(300. * i / (fSteps));
- sN = sigmaN * sqrt(300. * i /(fSteps-i));
-
-
- sP = (i<2 && dsP>0.3 && dsP<0.7)? 20. : sP; // square of (microns)
- sN = (i>fSteps-2 && dsN>0.3 && dsN<0.7)? 20. : sN; // square of (microns)
-
- sP = (i==2 && dsP>0.4 && dsP<0.6)? 15. : sP; // square of (microns)
- sN = (i==8 && dsN>0.4 && dsN<0.6)? 15. : sN; // square of (microns)
-
-
- //printf("i=%d SigmaP SigmaN sP sN %f %f %e %e\n",i,sigmaP, sigmaN,sP,sN);
-
- for(j=-1; j<2; j++) {
-
- if (stripP+j<0 || stripP+j>fNstrips) continue;
-
- signal = arrayEP[i] * TMath::Abs( (F(j+0.5-dsP,sP)-F(j-0.5-dsP,sP)) );
- //printf("SimSSD::HitsToDigits:%d arrayEP[%d]=%e signal=%e\n",j,i,arrayEP[i],signal);
- if (signal > noiseP/fSteps) {
- (*fP)[stripP+j] += signal;
- dict = (fTracksP+stripP+j);
- (*dict).AddTrack(track);
- }
- } // end for j loop over neighboring strips
- for(j=-1; j<2; j++) {
-
- if (stripN+j<0 || stripN+j>fNstrips) continue;
-
- signal = arrayEN[i] * TMath::Abs( (F(j+0.5-dsN,sN)-F(j-0.5-dsN,sN)) );
- //printf("SimSSD::HitsToDigits:%d arrayEN[%d]=%e signal=%e\n",j,i,arrayEN[i],signal);
- if (signal > noiseN/fSteps) {
- (*fN)[stripN+j] += signal;
- dict = (fTracksN+stripN+j); //co to jest
- (*dict).AddTrack(track);
- }
- } // end for j loop over neighboring strips
-
- xI += dx;
- zI += dz;
- }
-
+ fMapA2->ClearMap();
+}
+//----------------------------------------------------------------------
+void AliITSsimulationSSD::HitToDigit(Int_t module, Double_t x0, Double_t y0,
+ Double_t z0, Double_t x1, Double_t y1,
+ Double_t z1, Double_t de,
+ Int_t *indexRange, Bool_t first) {
+ // Turns hits in SSD module into one or more digits.
+
+ Float_t tang[2] = {0.0,0.0};
+ fSegmentation->Angles(tang[0], tang[1]);// stereo<< -> tan(stereo)~=stereo
+ Double_t x, y, z;
+ Double_t dex=0.0, dey=0.0, dez=0.0;
+ Double_t pairs;
+ Double_t ionE = 3.62E-9; // ionization energy of Si (GeV)
+ Double_t sigma[2] = {0.,0.};// standard deviation of the diffusion gaussian
+
+ Double_t D[2] = {11.,30.}; // diffusion constant {h,e} (cm**2/sec)
+ Double_t tdrift[2] = {0.,0.}; // time of drift
+ Double_t vdrift[2] = {0.86E6,2.28E6}; // drift velocity (cm/sec)
+ Double_t w;
+ Double_t inf[2], sup[2], par0[2];
+ // Steps in the module are determined "manually" (i.e. No Geant)
+ // NumOfSteps divide path between entering and exiting hits in steps
+ Int_t numOfSteps = NumOfSteps(x1, y1, z1, dex, dey, dez);
+
+ // Enery loss is equally distributed among steps
+ de = de/numOfSteps;
+ pairs = de/ionE; // e-h pairs generated
+
+ for(Int_t j=0; j<numOfSteps; j++) { // stepping
+ // cout<<"step number ="<<j<<endl;
+ x = x0 + (j+0.5)*dex;
+ y = y0 + (j+0.5)*dey;
+ //if ( y > (seg->Dy()/2 +10)*1.0E-4 ) {
+ if ( y > (fSegmentation->Dy()/2+10)*1.0E-4 ) {
+ // check if particle is within the detector
+ cout<<"AliITSsimulationSSD::HitToDigit: Warning: hit "
+ "out of detector y0,y,dey,j ="
+ <<y0<<","<<y<<","<<dey<<","<<j<<endl;
+ return;
+ } // end if
+ z = z0 + (j+0.5)*dez;
+
+ // calculate drift time
+ // y is the minimum path
+ tdrift[0] = (y+(fSegmentation->Dy()*1.0E-4)/2) / vdrift[0];
+ tdrift[1] = ((fSegmentation->Dy()*1.0E-4)/2-y) / vdrift[1];
+
+ for(Int_t k=0; k<2; k++) { // both sides remember: 0=Pside 1=Nside
+
+ tang[k]=TMath::Tan(tang[k]);
+
+ // w is the coord. perpendicular to the strips
+ if(k==0) {
+ //w=(x+(seg->Dx()*1.0E-4)/2)-(z+(seg->Dz()*1.0E-4)/2)*tang[k];
+ w = (x+(fSegmentation->Dx()*1.0E-4)/2) -
+ (z+(fSegmentation->Dz()*1.0E-4)/2)*tang[k];
+ }else{
+ //w =(x+(seg->Dx()*1.0E-4)/2)+(z-(seg->Dz()*1.0E-4)/2)*tang[k];
+ w = (x+(fSegmentation->Dx()*1.0E-4)/2) +
+ (z-(fSegmentation->Dz()*1.0E-4)/2)*tang[k];
+ //cout<<"k,x,z,w ="<<k<<","<<x<<","<<z<<","<<w<<endl;
+ } // end if
+ w = w / (fPitch*1.0E-4); // w is converted in units of pitch
+
+ if((w<(-0.5)) || (w>(fNstrips-0.5))) {
+ // this check rejects hits in regions not covered by strips
+ // 0.5 takes into account boundaries
+ if(k==0) cout<<"AliITSsimulationSSD::HitToDigit: "
+ "Warning: no strip in this region of P side"
+ <<endl;
+ else cout<<"AliITSsimulationSSD::HitToDigit: "
+ "Warning: no strip in this region of N side"<<endl;
+ return;
+ } // end if
+
+ // sigma is the standard deviation of the diffusion gaussian
+
+ if(tdrift[k]<0) return;
+
+ sigma[k] = TMath::Sqrt(2*D[k]*tdrift[k]);
+ sigma[k] = sigma[k] /(fPitch*1.0E-4); //units of Pitch
+ if(sigma[k]==0.0) {
+ cout<<"AliITSsimulationSSD::DigitiseModule: Error: sigma=0"
+ <<endl;
+ exit(0);
+ } // end if
+
+ par0[k] = pairs;
+ // we integrate the diffusion gaussian from -3sigma to 3sigma
+ inf[k] = w - 3*sigma[k]; // 3 sigma from the gaussian average
+ sup[k] = w + 3*sigma[k]; // 3 sigma from the gaussian average
+ // IntegrateGaussian does the actual
+ // integration of diffusion gaussian
+ IntegrateGaussian(k, par0[k], w, sigma[k], inf[k], sup[k],
+ indexRange, first);
+ } // end for loop over side (0=Pside, 1=Nside)
+ } // end stepping
+ //delete seg;
}
+//____________________________________________________________________--
+void AliITSsimulationSSD::ApplyNoise() {
+ // Apply Noise.
+
+ Float_t signal;
+ Float_t noise[2] = {0.,0.};
+ fResponse->GetNoiseParam(noise[0],noise[1]); // retrieves noise parameters
+ for(Int_t k=0;k<2;k++){ // both sides (0=Pside, 1=Nside)
+ for(Int_t ix=0;ix<fNstrips;ix++){ // loop over strips
+ signal = (Float_t) fMapA2->GetSignal(k,ix);// retrieves signal
+ // from map
-//____________________________________________________________________
-//
-// Private Methods for Simulation
-//______________________________________________________________________
-//
+ signal += gRandom->Gaus(0,noise[k]);// add noise to signal
+ if(signal<0.) signal=0.0; // in case noise is negative...
-void AliITSsimulationSSD::ApplyNoise() {
- // Apply Noise.
- Float_t noiseP, noiseN;
- fResponse->GetNoiseParam(noiseP,noiseN);
-
- Int_t i;
- for(i = 0; i<fNstrips; i++) {
- (*fP)[i] += gRandom->Gaus(0,noiseP);
- (*fN)[i] += gRandom->Gaus(0,noiseN);
- }
+ fMapA2->SetHit(k,ix,(Double_t)signal); // give back signal to map
+ } // loop over strip
+ } // loop over k (P or N side)
}
-
-//_________________________________________________________________________
-
+//______________________________________________________________________
void AliITSsimulationSSD::ApplyCoupling() {
- // Apply the effecto of electronic coupling between channels
-
- Int_t i;
- for(i = 1; i<fNstrips-1; i++) {
- (*fP)[i] += (*fP)[i-1]*fDCS->GetCouplingPL() + (*fP)[i+1]*fDCS->GetCouplingPR();
- (*fN)[i] += (*fN)[i-1]*fDCS->GetCouplingNL() + (*fN)[i+1]*fDCS->GetCouplingNR();
- }
+ // Apply the effect of electronic coupling between channels
+ Float_t signal, signalLeft=0, signalRight=0;
+
+ for(Int_t ix=0;ix<fNstrips;ix++){
+ if(ix>0.) signalLeft = (Float_t) fMapA2->GetSignal(0,ix-1)*
+ fDCS->GetCouplingPL();
+ else signalLeft = 0.0;
+ if(ix<(fNstrips-1)) signalRight = (Float_t) fMapA2->GetSignal(0,ix+1)*
+ fDCS->GetCouplingPR();
+ else signalRight = 0.0;
+ signal = (Float_t) fMapA2->GetSignal(0,ix);
+ signal += signalLeft + signalRight;
+ fMapA2->SetHit(0,ix,(Double_t)signal);
+
+ if(ix>0.) signalLeft = (Float_t) fMapA2->GetSignal(1,ix-1)*
+ fDCS->GetCouplingNL();
+ else signalLeft = 0.0;
+ if(ix<(fNstrips-1)) signalRight = (Float_t) fMapA2->GetSignal(1,ix+1)*
+ fDCS->GetCouplingNR();
+ else signalRight = 0.0;
+ signal = (Float_t) fMapA2->GetSignal(1,ix);
+ signal += signalLeft + signalRight;
+ fMapA2->SetHit(1,ix,(Double_t)signal);
+ } // loop over strips
}
-
-//__________________________________________________________________________
-
-void AliITSsimulationSSD::ApplyThreshold() {
- // Applies the effect of a threshold on the signals for digitization.
- Float_t noiseP, noiseN;
- fResponse->GetNoiseParam(noiseP,noiseN);
-
- // or introduce the SetThresholds in fResponse
-
- Int_t i;
- for(i=0; i<fNstrips; i++) {
- (*fP)[i] = ((*fP)[i] > noiseP*4) ? (*fP)[i] : 0;
- (*fN)[i] = ((*fN)[i] > noiseN*4) ? (*fN)[i] : 0;
- //printf("SSD:(*fP)[i] (*fN)[i] %f %f \n",(*fP)[i], (*fN)[i]);
- }
-
+//______________________________________________________________________
+Float_t AliITSsimulationSSD::F(Float_t av, Float_t x, Float_t s) {
+ // Computes the integral of a gaussian using Error Function
+ Float_t sqrt2 = TMath::Sqrt(2.0);
+ Float_t sigm2 = sqrt2*s;
+ Float_t integral;
+
+ integral = 0.5 * TMath::Erf( (x - av) / sigm2);
+ return integral;
}
-
-//__________________________________________________________________________
-
-void AliITSsimulationSSD::ApplyDAQ() {
- // Converts simulated signals to simulated ADC counts
- AliITS *its=(AliITS*)gAlice->GetModule("ITS");
-
- Float_t noiseP, noiseN;
- fResponse->GetNoiseParam(noiseP,noiseN);
-
- // Set signal = 0 if invalid strip
- Int_t i,j;
- for(i=0; i<fNstrips; i++) {
- if (!(fDCS->IsValidP(i))) (*fP)[i] = 0;
- if (!(fDCS->IsValidN(i))) (*fN)[i] = 0;
- }
-
- Int_t digits[3], tracks[3];
- Float_t charges[3];
- Float_t phys=0;
- for(i=0; i<fNstrips; i++) {
- if ((*fP)[i] < noiseP*4) continue;
- digits[0]=1;
- digits[1]=i;
- digits[2]=(int)(*fP)[i];
- for(j=0; j<(fTracksP+i)->GetNTracks(); j++) {
- if(j>2) continue;
- tracks[j] = (fTracksP+i)->GetTrack(j);
- charges[j] = 0;
- }
- its->AddDigit(2,phys,digits,tracks,charges);
-
- //cout << (fTracksP+i)->GetNTracks();
- //
- //if ((fTracksP+i)->GetNTracks() == 0) {
- // cout << d.fCoord2 << " " << d.fSignal << "\n";
- //}
- }
+//______________________________________________________________________
+void AliITSsimulationSSD::IntegrateGaussian(Int_t k,Double_t par, Double_t w,
+ Double_t sigma,
+ Double_t inf, Double_t sup,
+ Int_t *indexRange, Bool_t first) {
+ // integrate the diffusion gaussian
+ // remind: inf and sup are w-3sigma and w+3sigma
+ // we could define them here instead of passing them
+ // this way we are free to introduce asimmetry
+
+ Double_t a=0.0, b=0.0;
+ Double_t signal = 0.0, dXCharge1 = 0.0, dXCharge2 = 0.0;
+ // dXCharge1 and 2 are the charge to two neighbouring strips
+ // Watch that we only involve at least two strips
+ // Numbers greater than 2 of strips in a cluster depend on
+ // geometry of the track and delta rays, not charge diffusion!
+
+ Double_t strip = TMath::Floor(w); // clostest strip on the left
+
+ if ( TMath::Abs((strip - w)) < 0.5) {
+ // gaussian mean is closer to strip on the left
+ a = inf; // integration starting point
+ if((strip+0.5)<=sup) {
+ // this means that the tail of the gaussian goes beyond
+ // the middle point between strips ---> part of the signal
+ // is given to the strip on the right
+ b = strip + 0.5; // integration stopping point
+ dXCharge1 = F( w, b, sigma) - F(w, a, sigma);
+ dXCharge2 = F( w, sup, sigma) - F(w ,b, sigma);
+ }else {
+ // this means that all the charge is given to the strip on the left
+ b = sup;
+ dXCharge1 = 0.9973; // gaussian integral at 3 sigmas
+ dXCharge2 = 0.0;
+ } // end if
+
+ dXCharge1 = par * dXCharge1;// normalize by mean of number of carriers
+ dXCharge2 = par * dXCharge2;
+
+ // for the time being, signal is the charge
+ // in ChargeToSignal signal is converted in ADC channel
+ signal = fMapA2->GetSignal(k,strip);
+ signal += dXCharge1;
+
+ fMapA2->SetHit(k,strip,(Double_t)signal);
+ if(((Int_t) strip) < (fNstrips-1)) {
+ // strip doesn't have to be the last (remind: last=fNstrips-1)
+ // otherwise part of the charge is lost
+ signal = fMapA2->GetSignal(k,(strip+1));
+ signal += dXCharge2;
+ fMapA2->SetHit(k,(strip+1),(Double_t)signal);
+ } // end if
+ if(dXCharge1 > 1.) {
+ if (first) {
+ indexRange[k*2+0]=indexRange[k*2+1]=(Int_t) strip;
+ first=kFALSE;
+ } // end if first
+
+ indexRange[k*2+0]=TMath::Min(indexRange[k*2+0],(Int_t) strip);
+ indexRange[k*2+1]=TMath::Max(indexRange[k*2+1],(Int_t) strip);
+ } // dXCharge > 1 e-
+
+ }else{
+ // gaussian mean is closer to strip on the right
+ strip++; // move to strip on the rigth
+ b = sup; // now you know where to stop integrating
+ if((strip-0.5)>=inf) {
+ // tail of diffusion gaussian on the left goes left of
+ // middle point between strips
+ a = strip - 0.5; // integration starting point
+ dXCharge1 = F(w, b, sigma) - F(w, a, sigma);
+ dXCharge2 = F(w, a, sigma) - F(w, inf, sigma);
+ }else {
+ a = inf;
+ dXCharge1 = 0.9973; // gaussian integral at 3 sigmas
+ dXCharge2 = 0.0;
+ } // end if
- for(i=0; i<fNstrips; i++) {
- if ((*fN)[i] < noiseN*4) continue;
- digits[0]=0;
- digits[1]=i;
- digits[2]=(int)(*fN)[i];
- for(j=0; j<(fTracksN+i)->GetNTracks(); j++) {
- if(j>2) continue;
- tracks[j] = (fTracksN+i)->GetTrack(j);
- charges[j] = 0;
- }
- its->AddDigit(2,phys,digits,tracks,charges);
-
- //cout << (fTracksN+i)->GetNTracks();
- //if ((fTracksN+i)->GetNTracks() == 0) {
- // cout << d.fCoord2 << " " << d.fSignal << "\n";
- //}
- }
+ dXCharge1 = par * dXCharge1; // normalize by means of carriers
+ dXCharge2 = par * dXCharge2;
+
+ // for the time being, signal is the charge
+ // in ChargeToSignal signal is converted in ADC channel
+ signal = fMapA2->GetSignal(k,strip);
+ signal += dXCharge1;
+ fMapA2->SetHit(k,strip,(Double_t)signal);
+ if(((Int_t) strip) > 0) {
+ // strip doesn't have to be the first
+ // otherwise part of the charge is lost
+ signal = fMapA2->GetSignal(k,(strip-1));
+ signal += dXCharge2;
+ fMapA2->SetHit(k,(strip-1),(Double_t)signal);
+ } // end if
+ if(dXCharge1 > 1.) {
+ if (first) {
+ indexRange[k*2+0]=indexRange[k*2+1]=(Int_t) strip;
+ first=kFALSE;
+ } // end if first
+
+ indexRange[k*2+0]=TMath::Min(indexRange[k*2+0],(Int_t) strip);
+ indexRange[k*2+1]=TMath::Max(indexRange[k*2+1],(Int_t) strip);
+ } // dXCharge > 1 e-
+ } // end if
}
-
-
-//____________________________________________________________________________
-
-Float_t AliITSsimulationSSD::F(Float_t x, Float_t s) {
- // Computes the integral of a gaussian at the mean valuse x with sigma s.
- //printf("SDD:F(%e,%e)\n",x,s);
- return 0.5*TMath::Erf(x * fPitch / s) ;
-}
-
//______________________________________________________________________
+Int_t AliITSsimulationSSD::NumOfSteps(Double_t x, Double_t y, Double_t z,
+ Double_t & dex,Double_t & dey,Double_t & dez){
+ // number of steps
+ // it also returns steps for each coord
+ //AliITSsegmentationSSD *seg = new AliITSsegmentationSSD();
-Float_t AliITSsimulationSSD::Get2Strip(Int_t flag, Int_t iStrip, Float_t x, Float_t z){
- // Returns the relative space between two strips.
+ Double_t step = 25E-4;
+ //step = (Double_t) seg->GetStepSize(); // step size (cm)
+ Int_t numOfSteps = (Int_t) (TMath::Sqrt(x*x+y*y+z*z)/step);
- // flag==1 for Pside, 0 for Nside
+ if (numOfSteps < 1) numOfSteps = 1; // one step, at least
- Float_t stereoP, stereoN;
- fSegmentation->Angles(stereoP,stereoN);
-
- Float_t tanP=TMath::Tan(stereoP);
- Float_t tanN=TMath::Tan(stereoN);
-
- Float_t dx = fSegmentation->Dx();
- Float_t dz = fSegmentation->Dz();
+ // we could condition the stepping depending on the incident angle
+ // of the track
+ dex = x/numOfSteps;
+ dey = y/numOfSteps;
+ dez = z/numOfSteps;
+ return numOfSteps;
+}
+//----------------------------------------------------------------------
+void AliITSsimulationSSD::GetList(Int_t label,Float_t **pList,
+ Int_t *indexRange) {
+ // loop over nonzero digits
+ Int_t ix,globalIndex;
+ Float_t signal=0.;
+ Float_t highest,middle,lowest;
+ // printf("SPD-GetList: indexRange[0] indexRange[1] indexRange[2] indexRange[3] %d %d %d %d\n",indexRange[0], indexRange[1], indexRange[2], indexRange[3]);
+
+ for(Int_t k=0; k<2; k++) {
+ for(ix=indexRange[k*2+0];ix<indexRange[k*2+1]+1;ix++){
+ if(indexRange[k*2+0]<indexRange[k*2+1])
+ signal=fMapA2->GetSignal(k,ix);
+
+ globalIndex = k*fNstrips+ix; // globalIndex starts from 0!
+ if(!pList[globalIndex]){
+ //
+ //Create new list (6 elements-3 signals and 3 tracks+total sig)
+ //
+ pList[globalIndex] = new Float_t [6];
+ // set list to -1
+ *pList[globalIndex] = -2.;
+ *(pList[globalIndex]+1) = -2.;
+ *(pList[globalIndex]+2) = -2.;
+ *(pList[globalIndex]+3) = 0.;
+ *(pList[globalIndex]+4) = 0.;
+ *(pList[globalIndex]+5) = 0.;
+ *pList[globalIndex] = (float)label;
+ *(pList[globalIndex]+3) = signal;
+ }else{
+ // check the signal magnitude
+ highest = *(pList[globalIndex]+3);
+ middle = *(pList[globalIndex]+4);
+ lowest = *(pList[globalIndex]+5);
+ signal -= (highest+middle+lowest);
+ //
+ // compare the new signal with already existing list
+ //
+ if(signal<lowest) continue; // neglect this track
+ if (signal>highest){
+ *(pList[globalIndex]+5) = middle;
+ *(pList[globalIndex]+4) = highest;
+ *(pList[globalIndex]+3) = signal;
+ *(pList[globalIndex]+2) = *(pList[globalIndex]+1);
+ *(pList[globalIndex]+1) = *pList[globalIndex];
+ *pList[globalIndex] = label;
+ }else if (signal>middle){
+ *(pList[globalIndex]+5) = middle;
+ *(pList[globalIndex]+4) = signal;
+ *(pList[globalIndex]+2) = *(pList[globalIndex]+1);
+ *(pList[globalIndex]+1) = label;
+ }else{
+ *(pList[globalIndex]+5) = signal;
+ *(pList[globalIndex]+2) = label;
+ } // end if
+ } // end if
+ } // end of loop pixels in x
+ } // end of loop over pixels in z
+}
+//----------------------------------------------------------------------
+void AliITSsimulationSSD::ChargeToSignal(Float_t **pList) {
+ // charge to signal
+ AliITS *aliITS = (AliITS*)gAlice->GetModule("ITS");
+ Float_t threshold = 0.;
+ Int_t digits[3], tracks[3],hits[3],gi,j1;
+ Float_t charges[3];
+ Float_t signal,phys;
+ Float_t noise[2] = {0.,0.};
- x += dx/2;
- z += dz/2;
-
- if (flag) return (x - z*tanP) / fPitch - iStrip; // from 0 to 1
- else return (x - tanN*(dz - z)) / fPitch - iStrip;
+ fResponse->GetNoiseParam(noise[0],noise[1]);
+
+ for(Int_t k=0;k<2;k++){ // both sides (0=Pside, 1=Nside)
+
+ // Threshold for zero-suppression
+ // It can be defined in AliITSresponseSSD
+ // threshold = (Float_t)fResponse->MinVal(k);
+ // I prefer to think adjusting the threshold "manually", looking
+ // at the scope, and considering noise standard deviation
+ threshold = 4.0*noise[k]; // 4 times noise is a choice
+ for(Int_t ix=0;ix<fNstrips;ix++){ // loop over strips
+
+ signal = (Float_t) fMapA2->GetSignal(k,ix);
+
+ gi =k*fNstrips+ix; // global index
+ if (signal > threshold) {
+ digits[0]=k;
+ digits[1]=ix;
+
+ // convert to ADC signal
+ // conversion factor are rather arbitrary (need tuning)
+ // minimum ionizing particle--> ~30000 pairs--> ADC channel 50
+ signal = signal*50.0/30000.0;
+ if(signal>1000.) signal = 1000.0;//if exceeding, accumulate
+ // last one
+ digits[2]=(Int_t) signal;
+
+ //gi =k*fNstrips+ix; // global index
+ for(j1=0;j1<3;j1++){
+ if (pList[gi]) {
+ tracks[j1] = (Int_t)(*(pList[gi]+j1));
+ } else {
+ tracks[j1]=-2; //noise
+ } // end if pList
+ charges[j1] = 0;
+ } // end for j1
+
+ phys=0;
+
+ hits[0]=0;
+ hits[1]=0;
+ hits[2]=0;
+ // finally add digit
+ aliITS->AddSimDigit(2,phys,digits,tracks,hits,charges);
+
+ //if(pList[gi]) delete [] pList[gi];
+ } // end if signal > threshold
+ if(pList[gi]) delete [] pList[gi];
+ } // end for ix
+ } // end for k
+ delete [] pList;
}
-//____________________________________________________________________________
git://git.uio.no / u / mrichter / AliRoot.git / blobdiff