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 **************************************************************************/
20 #include <Riostream.h>
21 #include <TObjArray.h>
24 #include "AliITSmodule.h"
25 #include "AliITSMapA2.h"
26 #include "AliITSpList.h"
27 #include "AliITSCalibrationSSD.h"
28 #include "AliITSsegmentationSSD.h"
29 //#include "AliITSdcsSSD.h"
31 #include "AliITShit.h"
32 #include "AliITSdigitSSD.h"
34 #include "AliITSgeom.h"
35 #include "AliITSsimulationSSD.h"
36 #include "AliITSTableSSD.h"
37 //#include "AliITSresponseSSD.h"
39 ClassImp(AliITSsimulationSSD)
40 ////////////////////////////////////////////////////////////////////////
42 // Author: Enrico Fragiacomo //
43 // enrico.fragiacomo@ts.infn.it //
44 // Last revised: march 2006 //
46 // AliITSsimulationSSD is the simulation of SSD. //
47 ////////////////////////////////////////////////////////////////////////
49 //----------------------------------------------------------------------
50 AliITSsimulationSSD::AliITSsimulationSSD():AliITSsimulation(),
62 // A default construction AliITSsimulationSSD class
64 //----------------------------------------------------------------------
65 AliITSsimulationSSD::AliITSsimulationSSD(AliITSDetTypeSim* dettyp):
66 AliITSsimulation(dettyp),
74 // AliITSDetTypeSim Pointer to the SSD dettype to be used
78 // A standard constructed AliITSsimulationSSD class
82 //----------------------------------------------------------------------
83 void AliITSsimulationSSD::Init(){
84 // Inilizer, Inilizes all of the variable as needed in a standard place.
86 // AliITSsegmentationSSD *seg Pointer to the SSD segmentation to be used
87 // AliITSCalibrationSSD *resp Pointer to the SSD responce class to be used
92 AliITSsegmentationSSD* seg = (AliITSsegmentationSSD*)GetSegmentationModel(2);
94 SetDriftVelocity(); // use default values in .h file
95 SetIonizeE(); // use default values in .h file
96 SetDiffConst(); // use default values in .h file
97 fpList = new AliITSpList(2,GetNStrips());
98 fMapA2 = new AliITSMapA2(seg);
100 //______________________________________________________________________
101 AliITSsimulationSSD& AliITSsimulationSSD::operator=(
102 const AliITSsimulationSSD &s){
105 if(this==&s) return *this;
107 // this->fDCS = new AliITSdcsSSD(*(s.fDCS));
108 this->fMapA2 = s.fMapA2;
109 this->fIonE = s.fIonE;
110 this->fDifConst[0] = s.fDifConst[0];
111 this->fDifConst[1] = s.fDifConst[1];
112 this->fDriftVel[0] = s.fDriftVel[0];
113 this->fDriftVel[1] = s.fDriftVel[1];
117 //______________________________________________________________________
118 AliITSsimulation& AliITSsimulationSSD::operator=(
119 const AliITSsimulation &s){
122 if(this==&s) return *this;
123 Error("AliITSsimulationSSD","Not allowed to make a = with "
124 "AliITSsimulationSSD Using default creater instead");
129 //______________________________________________________________________
130 AliITSsimulationSSD::AliITSsimulationSSD(const AliITSsimulationSSD &source):
131 AliITSsimulation(source),
132 fMapA2(source.fMapA2),
137 fDifConst[0] = source.fDifConst[0];
138 fDifConst[1] = source.fDifConst[1];
139 fDriftVel[0] = source.fDriftVel[0];
140 fDriftVel[1] = source.fDriftVel[1];
142 //______________________________________________________________________
143 AliITSsimulationSSD::~AliITSsimulationSSD() {
148 //______________________________________________________________________
149 void AliITSsimulationSSD::InitSimulationModule(Int_t module,Int_t event){
150 // Creates maps to build the list of tracks for each sumable digit
152 // Int_t module // Module number to be simulated
153 // Int_t event // Event number to be simulated
159 SetModuleNumber(module);
160 SetEventNumber(event);
164 //______________________________________________________________________
165 void AliITSsimulationSSD::FinishSDigitiseModule(){
166 // Does the Sdigits to Digits work
174 FillMapFrompList(fpList); // need to check if needed here or not????
175 SDigitToDigit(fModule,fpList);
179 //______________________________________________________________________
180 void AliITSsimulationSSD::DigitiseModule(AliITSmodule *mod,Int_t,Int_t) {
181 // Digitizes hits for one SSD module
182 SetModuleNumber(mod->GetIndex());
184 HitsToAnalogDigits(mod,fpList);
185 SDigitToDigit(GetModuleNumber(),fpList);
190 //______________________________________________________________________
191 void AliITSsimulationSSD::SDigitiseModule(AliITSmodule *mod,Int_t,Int_t) {
192 // Produces Summable/Analog digits and writes them to the SDigit tree.
194 HitsToAnalogDigits(mod,fpList);
196 WriteSDigits(fpList);
201 //______________________________________________________________________
202 void AliITSsimulationSSD::SDigitToDigit(Int_t module,AliITSpList *pList){
203 // Takes the pList and finishes the digitization.
205 ApplyNoise(pList,module);
206 ApplyCoupling(pList,module);
207 ApplyDeadChannels(module);
209 ChargeToSignal(module,pList);
211 //______________________________________________________________________
212 void AliITSsimulationSSD::HitsToAnalogDigits(AliITSmodule *mod,
214 // Loops over all hits to produce Analog/floating point digits. This
215 // is also the first task in producing standard digits.
216 Int_t lasttrack = -2;
218 Double_t x0=0.0, y0=0.0, z0=0.0;
219 Double_t x1=0.0, y1=0.0, z1=0.0;
221 Int_t module = mod->GetIndex();
223 AliITSsegmentationSSD* seg = (AliITSsegmentationSSD*)GetSegmentationModel(2);
225 TObjArray *hits = mod->GetHits();
226 Int_t nhits = hits->GetEntriesFast();
227 if (nhits<=0) return;
228 AliITSTableSSD * tav = new AliITSTableSSD(GetNStrips());
229 module = mod->GetIndex();
230 if ( mod->GetLayer() == 6 ) seg->SetLayer(6);
231 if ( mod->GetLayer() == 5 ) seg->SetLayer(5);
232 for(Int_t i=0; i<nhits; i++) {
233 // LineSegmentL returns 0 if the hit is entering
234 // If hits is exiting returns positions of entering and exiting hits
235 // Returns also energy loss
238 cout << mod->GetHit(i)->GetXL() << " "<<mod->GetHit(i)->GetYL();
239 cout << " " << mod->GetHit(i)->GetZL();
242 if (mod->LineSegmentL(i, x0, x1, y0, y1, z0, z1, de, idtrack)) {
243 HitToDigit(module, x0, y0, z0, x1, y1, z1, de,tav);
244 if (lasttrack != idtrack || i==(nhits-1)) {
245 GetList(idtrack,i,module,pList,tav);
249 } // end loop over hits
253 //----------------------------------------------------------------------
254 void AliITSsimulationSSD::HitToDigit(Int_t module, Double_t x0, Double_t y0,
255 Double_t z0, Double_t x1, Double_t y1,
256 Double_t z1, Double_t de,
257 AliITSTableSSD *tav) {
259 // hit to digit conversion
261 AliITSsegmentationSSD* seg = (AliITSsegmentationSSD*)GetSegmentationModel(2);
262 // Turns hits in SSD module into one or more digits.
263 Float_t tang[2] = {0.0,0.0};
264 seg->Angles(tang[0], tang[1]);//stereo<<->tan(stereo)~=stereo
266 Double_t dex=0.0, dey=0.0, dez=0.0;
267 Double_t pairs; // pair generation energy per step.
268 Double_t sigma[2] = {0.,0.};// standard deviation of the diffusion gaussian
269 Double_t tdrift[2] = {0.,0.}; // time of drift
271 Double_t inf[2], sup[2], par0[2];
273 // Steps in the module are determined "manually" (i.e. No Geant)
274 // NumOfSteps divide path between entering and exiting hits in steps
275 Int_t numOfSteps = NumOfSteps(x1, y1, z1, dex, dey, dez);
276 // Enery loss is equally distributed among steps
278 pairs = de/GetIonizeE(); // e-h pairs generated
279 for(Int_t j=0; j<numOfSteps; j++) { // stepping
280 x = x0 + (j+0.5)*dex;
281 y = y0 + (j+0.5)*dey;
282 if ( y > (seg->Dy()/2+10)*1.0E-4 ) {
283 // check if particle is within the detector
284 Warning("HitToDigit",
285 "hit out of detector y0=%e,y=%e,dey=%e,j =%d module=%d, exceed=%e",
286 y0,y,dey,j,module, y-(seg->Dy()/2+10)*1.0E-4);
289 z = z0 + (j+0.5)*dez;
290 if(GetDebug(4)) cout <<"HitToDigit "<<x<<" "<<y<<" "<<z<< " "
291 <<dex<<" "<<dey<<" "<<dez<<endl;
292 // calculate drift time
293 // y is the minimum path
294 tdrift[0] = (y+(seg->Dy()*1.0E-4)/2)/GetDriftVelocity(0);
295 tdrift[1] = ((seg->Dy()*1.0E-4)/2-y)/GetDriftVelocity(1);
297 for(Int_t k=0; k<2; k++) { // both sides remember: 0=Pside 1=Nside
299 tang[k]=TMath::Tan(tang[k]);
301 // w is the coord. perpendicular to the strips
302 Float_t xp=x*1.e+4,zp=z*1.e+4; // microns
303 seg->GetPadTxz(xp,zp);
304 if(k==0) w = xp; // P side strip number
305 else w = zp; // N side strip number
307 if((w<(-0.5)) || (w>(GetNStrips()-0.5))) {
308 // this check rejects hits in regions not covered by strips
309 // 0.5 takes into account boundaries
310 if(GetDebug(4)) cout << "x,z="<<x<<","<<z<<" w="<<w
311 <<" Nstrips="<<GetNStrips()<<endl;
312 return; // There are dead region on the SSD sensitive volume.
315 // sigma is the standard deviation of the diffusion gaussian
316 if(tdrift[k]<0) return;
317 sigma[k] = TMath::Sqrt(2*GetDiffConst(k)*tdrift[k]);
318 sigma[k] /= (GetStripPitch()*1.0E-4); //units of Pitch
320 Error("HitToDigit"," sigma[%d]=0",k);
325 // we integrate the diffusion gaussian from -3sigma to 3sigma
326 inf[k] = w - 3*sigma[k]; // 3 sigma from the gaussian average
327 sup[k] = w + 3*sigma[k]; // 3 sigma from the gaussian average
328 // IntegrateGaussian does the actual
329 // integration of diffusion gaussian
330 IntegrateGaussian(k, par0[k], w, sigma[k], inf[k], sup[k],tav);
331 } // end for loop over side (0=Pside, 1=Nside)
335 //______________________________________________________________________
336 void AliITSsimulationSSD::ApplyNoise(AliITSpList *pList,Int_t module){
339 Double_t signal,noise;
340 AliITSCalibrationSSD* res =(AliITSCalibrationSSD*)GetCalibrationModel(module);
343 for(ix=0;ix<GetNStrips();ix++){ // loop over strips
346 noise = (Double_t) gRandom->Gaus(0,res->GetNoiseP().At(ix));
348 // need to calibrate noise
349 // NOTE. noise from the calibration database comes uncalibrated,
350 // it needs to be calibrated in order to be added
351 // to the signal. It will be decalibrated later on together with the noise
352 noise *= (Double_t) res->GetGainP(ix);
354 // noise comes in ADC channels from the calibration database
355 // It needs to be converted back to electronVolts
356 noise /= res->GetDEvToADC(1.);
358 // Finally, noise is added to the signal
359 signal = noise + fMapA2->GetSignal(0,ix);//get signal from map
360 fMapA2->SetHit(0,ix,signal); // give back signal to map
361 if(signal>0.0) pList->AddNoise(0,ix,module,noise);
365 for(ix=0;ix<GetNStrips();ix++){ // loop over strips
366 noise = (Double_t) gRandom->Gaus(0,res->GetNoiseN().At(ix));// give noise to signal
367 noise *= (Double_t) res->GetGainN(ix);
368 noise /= res->GetDEvToADC(1.);
369 signal = noise + fMapA2->GetSignal(1,ix);//get signal from map
370 fMapA2->SetHit(1,ix,signal); // give back signal to map
371 if(signal>0.0) pList->AddNoise(1,ix,module,noise);
375 //______________________________________________________________________
376 void AliITSsimulationSSD::ApplyCoupling(AliITSpList *pList,Int_t module) {
377 // Apply the effect of electronic coupling between channels
380 AliITSCalibrationSSD* res =(AliITSCalibrationSSD*)GetCalibrationModel(module);
382 Double_t *contrLeft = new Double_t[GetNStrips()];
383 Double_t *contrRight = new Double_t[GetNStrips()];
386 for(ix=0;ix<GetNStrips();ix++){
387 if(ix>0) contrLeft[ix] = fMapA2->GetSignal(0,ix-1)*res->GetCouplingPL();
388 else contrLeft[ix] = 0.0;
389 if(ix<(GetNStrips()-1)) contrRight[ix] = fMapA2->GetSignal(0,ix+1)*res->GetCouplingPR();
390 else contrRight[ix] = 0.0;
391 } // loop over strips
393 for(ix=0;ix<GetNStrips();ix++){
394 signal = contrLeft[ix] + contrRight[ix] - res->GetCouplingPL() * fMapA2->GetSignal(0,ix)
395 - res->GetCouplingPR() * fMapA2->GetSignal(0,ix);
396 fMapA2->AddSignal(0,ix,signal);
397 if(signal>0.0) pList->AddNoise(0,ix,module,signal);
398 } // loop over strips
401 for(ix=0;ix<GetNStrips();ix++){
402 if(ix>0) contrLeft[ix] = fMapA2->GetSignal(1,ix-1)*res->GetCouplingNL();
403 else contrLeft[ix] = 0.0;
404 if(ix<(GetNStrips()-1)) contrRight[ix] = fMapA2->GetSignal(1,ix+1)*res->GetCouplingNR();
405 else contrRight[ix] = 0.0;
406 } // loop over strips
408 for(ix=0;ix<GetNStrips();ix++){
409 signal = contrLeft[ix] + contrRight[ix] - res->GetCouplingNL() * fMapA2->GetSignal(0,ix)
410 - res->GetCouplingNR() * fMapA2->GetSignal(0,ix);
411 fMapA2->AddSignal(1,ix,signal);
412 if(signal>0.0) pList->AddNoise(1,ix,module,signal);
413 } // loop over strips
417 delete [] contrRight;
420 //______________________________________________________________________
421 void AliITSsimulationSSD::ApplyDeadChannels(Int_t module) {
422 // Kill dead channels setting gain to zero
426 AliITSCalibrationSSD* res = (AliITSCalibrationSSD*)GetCalibrationModel(module);
428 deadentries = res->GetDeadPChannelsList().GetSize();
429 //cout<<module<<" "<<deadentries<<endl;
430 for(Int_t i=0; i<deadentries; i++) {
431 res->AddGainP(res->GetDeadPChannelsList().At(i),0.0);
434 deadentries = res->GetDeadNChannelsList().GetSize();
435 for(Int_t i=0; i<deadentries; i++) {
436 res->AddGainN(res->GetDeadNChannelsList().At(i),0.0);
441 //______________________________________________________________________
442 Float_t AliITSsimulationSSD::F(Float_t av, Float_t x, Float_t s) {
443 // Computes the integral of a gaussian using Error Function
444 Float_t sqrt2 = TMath::Sqrt(2.0);
445 Float_t sigm2 = sqrt2*s;
448 integral = 0.5 * TMath::Erf( (x - av) / sigm2);
451 //______________________________________________________________________
452 void AliITSsimulationSSD::IntegrateGaussian(Int_t k,Double_t par, Double_t w,
454 Double_t inf, Double_t sup,
455 AliITSTableSSD *tav) {
456 // integrate the diffusion gaussian
457 // remind: inf and sup are w-3sigma and w+3sigma
458 // we could define them here instead of passing them
459 // this way we are free to introduce asimmetry
461 Double_t a=0.0, b=0.0;
462 Double_t dXCharge1 = 0.0, dXCharge2 = 0.0;
463 // dXCharge1 and 2 are the charge to two neighbouring strips
464 // Watch that we only involve at least two strips
465 // Numbers greater than 2 of strips in a cluster depend on
466 // geometry of the track and delta rays, not charge diffusion!
468 Double_t strip = TMath::Floor(w); // closest strip on the left
470 if ( TMath::Abs((strip - w)) < 0.5) {
471 // gaussian mean is closer to strip on the left
472 a = inf; // integration starting point
473 if((strip+0.5)<=sup) {
474 // this means that the tail of the gaussian goes beyond
475 // the middle point between strips ---> part of the signal
476 // is given to the strip on the right
477 b = strip + 0.5; // integration stopping point
478 dXCharge1 = F( w, b, sigma) - F(w, a, sigma);
479 dXCharge2 = F( w, sup, sigma) - F(w ,b, sigma);
481 // this means that all the charge is given to the strip on the left
483 dXCharge1 = 0.9973; // gaussian integral at 3 sigmas
486 dXCharge1 = par * dXCharge1;// normalize by mean of number of carriers
487 dXCharge2 = par * dXCharge2;
489 // for the time being, signal is the charge
490 // in ChargeToSignal signal is converted in ADC channel
491 fMapA2->AddSignal(k,(Int_t)strip,dXCharge1);
492 tav->Add(k,(Int_t)strip);
493 if(((Int_t) strip) < (GetNStrips()-1)) {
494 // strip doesn't have to be the last (remind: last=GetNStrips()-1)
495 // otherwise part of the charge is lost
496 fMapA2->AddSignal(k,((Int_t)strip+1),dXCharge2);
497 tav->Add(k,((Int_t)(strip+1)));
500 // gaussian mean is closer to strip on the right
501 strip++; // move to strip on the rigth
502 b = sup; // now you know where to stop integrating
503 if((strip-0.5)>=inf) {
504 // tail of diffusion gaussian on the left goes left of
505 // middle point between strips
506 a = strip - 0.5; // integration starting point
507 dXCharge1 = F(w, b, sigma) - F(w, a, sigma);
508 dXCharge2 = F(w, a, sigma) - F(w, inf, sigma);
511 dXCharge1 = 0.9973; // gaussian integral at 3 sigmas
514 dXCharge1 = par * dXCharge1; // normalize by means of carriers
515 dXCharge2 = par * dXCharge2;
516 // for the time being, signal is the charge
517 // in ChargeToSignal signal is converted in ADC channel
518 fMapA2->AddSignal(k,(Int_t)strip,dXCharge1);
519 tav->Add(k,(Int_t)strip);
520 if(((Int_t) strip) > 0) {
521 // strip doesn't have to be the first
522 // otherwise part of the charge is lost
523 fMapA2->AddSignal(k,((Int_t)strip-1),dXCharge2);
524 tav->Add(k,((Int_t)(strip-1)));
528 //______________________________________________________________________
529 Int_t AliITSsimulationSSD::NumOfSteps(Double_t x, Double_t y, Double_t z,
530 Double_t &dex,Double_t &dey,
533 // it also returns steps for each coord
534 //AliITSsegmentationSSD *seg = new AliITSsegmentationSSD();
536 Double_t step = 25E-4;
537 //step = (Double_t) seg->GetStepSize(); // step size (cm)
538 Int_t numOfSteps = (Int_t) (TMath::Sqrt(x*x+y*y+z*z)/step);
540 if (numOfSteps < 1) numOfSteps = 1; // one step, at least
543 // we could condition the stepping depending on the incident angle
551 //----------------------------------------------------------------------
552 void AliITSsimulationSSD::GetList(Int_t label,Int_t hit,Int_t mod,
553 AliITSpList *pList,AliITSTableSSD *tav) {
554 // loop over nonzero digits
558 for(Int_t k=0; k<2; k++) {
561 signal = fMapA2->GetSignal(k,ix);
565 } // end if signal==0.0
566 // check the signal magnitude
567 for(i=0;i<pList->GetNSignals(k,ix);i++){
568 signal -= pList->GetTSignal(k,ix,i);
570 // compare the new signal with already existing list
571 if(signal>0)pList->AddSignal(k,ix,label,hit,mod,signal);
573 } // end of loop on strips
574 } // end of loop on P/N side
577 //----------------------------------------------------------------------
578 void AliITSsimulationSSD::ChargeToSignal(Int_t module,AliITSpList *pList) {
580 static AliITS *aliITS = (AliITS*)gAlice->GetModule("ITS");
581 Float_t threshold = 0.;
582 Int_t size = AliITSdigitSSD::GetNTracks();
583 Int_t * digits = new Int_t[size];
584 Int_t * tracks = new Int_t[size];
585 Int_t * hits = new Int_t[size];
587 Float_t charges[3] = {0.0,0.0,0.0};
589 AliITSCalibrationSSD* res =(AliITSCalibrationSSD*)GetCalibrationModel(module);
591 for(Int_t k=0;k<2;k++){ // both sides (0=Pside, 1=Nside)
592 for(Int_t ix=0;ix<GetNStrips();ix++){ // loop over strips
594 // if strip is dead -> gain=0
595 if( ((k==0)&&(res->GetGainP(ix)==0)) || ((k==1)&&(res->GetGainN(ix)==0))) continue;
597 signal = fMapA2->GetSignal(k,ix);
598 // signal has to be uncalibrated
599 // In real life, gains are supposed to be calculated from calibration runs,
600 // stored in the calibration DB and used in the reconstruction
601 // (see AliITSClusterFinderSSD.cxx)
602 if(k==0) signal /= res->GetGainP(ix);
603 else signal /= res->GetGainN(ix);
605 // signal is converted in unit of ADC
606 signal = res->GetDEvToADC(signal);
607 if(signal>4096.) signal = 4096.;//if exceeding, accumulate last one
609 // threshold for zero suppression is set on the basis of the noise
610 // A good value is 3*sigma_noise
611 if(k==0) threshold = res->GetNoiseP().At(ix);
612 else threshold = res->GetNoiseN().At(ix);
613 threshold *= res->GetZSThreshold(); // threshold at 3 sigma noise
614 if(signal < threshold) continue;
618 digits[2] = TMath::Nint(signal);
619 for(j1=0;j1<size;j1++)if(j1<pList->GetNEntries()){
620 // only three in digit.
621 tracks[j1] = pList->GetTrack(k,ix,j1);
622 hits[j1] = pList->GetHit(k,ix,j1);
628 aliITS->AddSimDigit(2,0,digits,tracks,hits,charges);
635 //______________________________________________________________________
636 void AliITSsimulationSSD::WriteSDigits(AliITSpList *pList){
637 // Fills the Summable digits Tree
639 static AliITS *aliITS = (AliITS*)gAlice->GetModule("ITS");
641 pList->GetMaxMapIndex(ni,nj);
642 for(i=0;i<ni;i++)for(j=0;j<nj;j++){
643 if(pList->GetSignalOnly(i,j)>0.0){
644 aliITS->AddSumDigit(*(pList->GetpListItem(i,j)));
645 if(GetDebug(4)) cout << "pListSSD: "<<*(pList->GetpListItem(i,j))
651 //______________________________________________________________________
652 void AliITSsimulationSSD::FillMapFrompList(AliITSpList *pList){
653 // Fills fMap2A from the pList of Summable digits
656 for(k=0;k<2;k++)for(ix=0;ix<GetNStrips();ix++)
657 fMapA2->AddSignal(k,ix,pList->GetSignal(k,ix));
660 //______________________________________________________________________
661 void AliITSsimulationSSD::Print(ostream *os){
662 //Standard output format for this class
664 //AliITSsimulation::Print(os);
666 *os << fDifConst[0] <<","<< fDifConst[1] <<",";
667 *os << fDriftVel[0] <<","<< fDriftVel[1];
668 //*os <<","; fDCS->Print(os);
669 //*os <<","; fMapA2->Print(os);
671 //______________________________________________________________________
672 void AliITSsimulationSSD::Read(istream *is){
673 // Standard output streaming function.
675 //AliITSsimulation::Read(is);
677 *is >> fDifConst[0] >> fDifConst[1];
678 *is >> fDriftVel[0] >> fDriftVel[1];
682 //______________________________________________________________________
683 ostream &operator<<(ostream &os,AliITSsimulationSSD &source){
684 // Standard output streaming function.
689 //______________________________________________________________________
690 istream &operator>>(istream &os,AliITSsimulationSSD &source){
691 // Standard output streaming function.
696 //______________________________________________________________________