1 /**************************************************************************
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4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
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14 **************************************************************************/
18 //_________________________________________________________________________
19 // Implementation version v1 of PHOS Manager class
21 // Layout EMC + PPSD has name GPS2:
22 // Produces cumulated hits
24 // Layout EMC + CPV has name IHEP:
25 // Produces hits for CPV, cumulated hits
27 // Layout EMC + CPV + PPSD has name GPS:
28 // Produces hits for CPV, cumulated hits
30 //*-- Author: Yves Schutz (SUBATECH)
33 // --- ROOT system ---
39 #include "TParticle.h"
41 // --- Standard library ---
46 #include <strstream.h>
48 // --- AliRoot header files ---
50 #include "AliPHOSv1.h"
51 #include "AliPHOSHit.h"
52 #include "AliPHOSCPVDigit.h"
56 #include "AliPHOSGeometry.h"
57 #include "AliPHOSQAIntCheckable.h"
58 #include "AliPHOSQAFloatCheckable.h"
59 #include "AliPHOSQAMeanChecker.h"
63 //____________________________________________________________________________
64 AliPHOSv1::AliPHOSv1():
67 // default ctor: initialze data memebers
73 fLightYieldMean = 0. ;
74 fIntrinsicPINEfficiency = 0. ;
75 fLightYieldAttenuation = 0. ;
76 fRecalibrationFactor = 0. ;
77 fElectronsPerGeV = 0. ;
84 //____________________________________________________________________________
85 AliPHOSv1::AliPHOSv1(const char *name, const char *title):
90 // - fHits (the "normal" one), which retains the hits associated with
91 // the current primary particle being tracked
92 // (this array is reset after each primary has been tracked).
97 // We do not want to save in TreeH the raw hits
98 // But save the cumulated hits instead (need to create the branch myself)
99 // It is put in the Digit Tree because the TreeH is filled after each primary
100 // and the TreeD at the end of the event (branch is set in FinishEvent() ).
102 fHits= new TClonesArray("AliPHOSHit",1000) ;
103 gAlice->AddHitList(fHits) ;
107 fIshunt = 2 ; // All hits are associated with primary particles
109 //Photoelectron statistics:
110 // The light yield is a poissonian distribution of the number of
111 // photons created in the PbWo4 crystal, calculated using following formula
112 // NumberOfPhotons = EnergyLost * LightYieldMean* APDEfficiency *
113 // exp (-LightYieldAttenuation * DistanceToPINdiodeFromTheHit);
114 // LightYieldMean is parameter calculated to be over 47000 photons per GeV
115 // APDEfficiency is 0.02655
116 // k_0 is 0.0045 from Valery Antonenko
117 // The number of electrons created in the APD is
118 // NumberOfElectrons = APDGain * LightYield
119 // The APD Gain is 300
120 fLightYieldMean = 47000;
121 fIntrinsicPINEfficiency = 0.02655 ; //APD= 0.1875/0.1271 * 0.018 (PIN)
122 fLightYieldAttenuation = 0.0045 ;
123 fRecalibrationFactor = 13.418/ fLightYieldMean ;
124 fElectronsPerGeV = 2.77e+8 ;
126 fLightFactor = fLightYieldMean * fIntrinsicPINEfficiency ;
127 fAPDFactor = (fRecalibrationFactor/100.) * fAPDGain ;
130 Int_t nb = GetGeometry()->GetNModules() ;
133 fQAHitsMul = new AliPHOSQAIntCheckable("HitsM") ;
134 fQATotEner = new AliPHOSQAFloatCheckable("TotEn") ;
135 fQAHitsMulB = new TClonesArray("AliPHOSQAIntCheckable",nb) ;
136 fQATotEnerB = new TClonesArray("AliPHOSQAFloatCheckable", nb);
139 for ( i = 0 ; i < nb ; i++ ) {
140 sprintf(tempo, "HitsMB%d", i+1) ;
141 new( (*fQAHitsMulB)[i]) AliPHOSQAIntCheckable(tempo) ;
142 sprintf(tempo, "TotEnB%d", i+1) ;
143 new( (*fQATotEnerB)[i] ) AliPHOSQAFloatCheckable(tempo) ;
146 AliPHOSQAMeanChecker * hmc = new AliPHOSQAMeanChecker("HitsMul", 100. ,25.) ;
147 AliPHOSQAMeanChecker * emc = new AliPHOSQAMeanChecker("TotEner", 10. ,5.) ;
148 AliPHOSQAMeanChecker * bhmc = new AliPHOSQAMeanChecker("HitsMulB", 100. ,5.) ;
149 AliPHOSQAMeanChecker * bemc = new AliPHOSQAMeanChecker("TotEnerB", 2. ,.5) ;
151 // associate checkables and checkers
152 fQAHitsMul->AddChecker(hmc) ;
153 fQATotEner->AddChecker(emc) ;
154 for ( i = 0 ; i < nb ; i++ ) {
155 (static_cast<AliPHOSQAIntCheckable*>((*fQAHitsMulB)[i]))->AddChecker(bhmc) ;
156 (static_cast<AliPHOSQAFloatCheckable*>((*fQATotEnerB)[i]))->AddChecker(bemc) ;
161 //____________________________________________________________________________
162 AliPHOSv1::~AliPHOSv1()
175 //____________________________________________________________________________
176 void AliPHOSv1::AddHit(Int_t shunt, Int_t primary, Int_t tracknumber, Int_t Id, Float_t * hits)
178 // Add a hit to the hit list.
179 // A PHOS hit is the sum of all hits in a single crystal from one primary and within some time gate
184 Bool_t deja = kFALSE ;
185 AliPHOSGeometry * geom = GetGeometry() ;
187 newHit = new AliPHOSHit(shunt, primary, tracknumber, Id, hits) ;
189 for ( hitCounter = fNhits-1 ; hitCounter >= 0 && !deja ; hitCounter-- ) {
190 curHit = dynamic_cast<AliPHOSHit*>((*fHits)[hitCounter]) ;
191 if(curHit->GetPrimary() != primary) break ;
192 // We add hits with the same primary, while GEANT treats primaries succesively
193 if( *curHit == *newHit ) {
200 new((*fHits)[fNhits]) AliPHOSHit(*newHit) ;
201 // get the block Id number
203 geom->AbsToRelNumbering(Id, relid) ;
204 // and fill the relevant QA checkable (only if in PbW04)
205 if ( relid[1] == 0 ) {
206 fQAHitsMul->Update(1) ;
207 (static_cast<AliPHOSQAIntCheckable*>((*fQAHitsMulB)[relid[0]-1]))->Update(1) ;
215 //____________________________________________________________________________
216 void AliPHOSv1::FinishPrimary()
218 // called at the end of each track (primary) by AliRun
219 // hits are reset for each new track
220 // accumulate the total hit-multiplicity
222 // fQAHitsMul->Update( fHits->GetEntriesFast() ) ;
226 //____________________________________________________________________________
227 void AliPHOSv1::FinishEvent()
229 // called at the end of each event by AliRun
230 // accumulate the hit-multiplicity and total energy per block
231 // if the values have been updated check it
234 if ( fQATotEner->HasChanged() ) {
235 fQATotEner->CheckMe() ;
236 fQATotEner->Reset() ;
241 if ( fQAHitsMulB && fQATotEnerB ) {
242 for (i = 0 ; i < GetGeometry()->GetNModules() ; i++) {
243 AliPHOSQAIntCheckable * ci = static_cast<AliPHOSQAIntCheckable*>((*fQAHitsMulB)[i]) ;
244 AliPHOSQAFloatCheckable* cf = static_cast<AliPHOSQAFloatCheckable*>((*fQATotEnerB)[i]) ;
245 if ( ci->HasChanged() ) {
249 if ( cf->HasChanged() ) {
256 // check the total multiplicity
259 if ( fQAHitsMul->HasChanged() ) {
260 fQAHitsMul->CheckMe() ;
261 fQAHitsMul->Reset() ;
265 //____________________________________________________________________________
266 void AliPHOSv1::StepManager(void)
268 // Accumulates hits as long as the track stays in a single crystal or CPV gas Cell
270 Int_t relid[4] ; // (box, layer, row, column) indices
271 Int_t absid ; // absolute cell ID number
272 Float_t xyze[5]={-1000,-1000,-1000,0,0} ; // position wrt MRS, time and energy deposited
273 TLorentzVector pos ; // Lorentz vector of the track current position
276 Int_t tracknumber = gAlice->CurrentTrack() ;
277 Int_t primary = gAlice->GetPrimary( gAlice->CurrentTrack() );
278 TString name = GetGeometry()->GetName() ;
282 if( gMC->CurrentVolID(copy) == gMC->VolId("PCPQ") &&
283 (gMC->IsTrackEntering() ) &&
284 gMC->TrackCharge() != 0) {
286 gMC -> TrackPosition(pos);
288 Float_t xyzm[3], xyzd[3] ;
290 for (i=0; i<3; i++) xyzm[i] = pos[i];
291 gMC -> Gmtod (xyzm, xyzd, 1); // transform coordinate from master to daughter system
293 Float_t xyd[3]={0,0,0} ; //local posiiton of the entering
298 // Current momentum of the hit's track in the local ref. system
299 TLorentzVector pmom ; //momentum of the particle initiated hit
300 gMC -> TrackMomentum(pmom);
301 Float_t pm[3], pd[3];
305 gMC -> Gmtod (pm, pd, 2); // transform 3-momentum from master to daughter system
310 // Digitize the current CPV hit:
312 // 1. find pad response and
313 gMC->CurrentVolOffID(3,moduleNumber);
316 TClonesArray *cpvDigits = new TClonesArray("AliPHOSCPVDigit",0); // array of digits for current hit
317 CPVDigitize(pmom,xyd,moduleNumber,cpvDigits);
322 Int_t idigit,ndigits;
324 // 2. go through the current digit list and sum digits in pads
326 ndigits = cpvDigits->GetEntriesFast();
327 for (idigit=0; idigit<ndigits-1; idigit++) {
328 AliPHOSCPVDigit *cpvDigit1 = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(idigit));
329 Float_t x1 = cpvDigit1->GetXpad() ;
330 Float_t z1 = cpvDigit1->GetYpad() ;
331 for (Int_t jdigit=idigit+1; jdigit<ndigits; jdigit++) {
332 AliPHOSCPVDigit *cpvDigit2 = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(jdigit));
333 Float_t x2 = cpvDigit2->GetXpad() ;
334 Float_t z2 = cpvDigit2->GetYpad() ;
335 if (x1==x2 && z1==z2) {
336 Float_t qsum = cpvDigit1->GetQpad() + cpvDigit2->GetQpad() ;
337 cpvDigit2->SetQpad(qsum) ;
338 cpvDigits->RemoveAt(idigit) ;
342 cpvDigits->Compress() ;
344 // 3. add digits to temporary hit list fTmpHits
346 ndigits = cpvDigits->GetEntriesFast();
347 for (idigit=0; idigit<ndigits; idigit++) {
348 AliPHOSCPVDigit *cpvDigit = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(idigit));
349 relid[0] = moduleNumber + 1 ; // CPV (or PHOS) module number
350 relid[1] =-1 ; // means CPV
351 relid[2] = cpvDigit->GetXpad() ; // column number of a pad
352 relid[3] = cpvDigit->GetYpad() ; // row number of a pad
354 // get the absolute Id number
355 GetGeometry()->RelToAbsNumbering(relid, absid) ;
357 // add current digit to the temporary hit list
359 xyze[3] = gMC->TrackTime() ;
360 xyze[4] = cpvDigit->GetQpad() ; // amplitude in a pad
361 primary = -1; // No need in primary for CPV
362 AddHit(fIshunt, primary, tracknumber, absid, xyze);
364 if (cpvDigit->GetQpad() > 0.02) {
365 xmean += cpvDigit->GetQpad() * (cpvDigit->GetXpad() + 0.5);
366 zmean += cpvDigit->GetQpad() * (cpvDigit->GetYpad() + 0.5);
367 qsum += cpvDigit->GetQpad();
379 if(gMC->CurrentVolID(copy) == gMC->VolId("PXTL") ) { // We are inside a PBWO crystal
381 gMC->TrackPosition(pos) ;
386 Float_t global[3], local[3] ;
390 Float_t lostenergy = gMC->Edep();
392 //Put in the TreeK particle entering PHOS and all its parents
393 if ( gMC->IsTrackEntering() ){
395 gMC -> Gmtod (xyze, xyzd, 1); // transform coordinate from master to daughter system
396 if (xyzd[1] > GetGeometry()->GetCrystalSize(1)/2-0.002 ||
397 xyzd[1] < -GetGeometry()->GetCrystalSize(1)/2+0.002) {
398 TParticle * part = 0 ;
399 Int_t parent = gAlice->CurrentTrack() ;
400 while ( parent != -1 ) {
401 part = gAlice->Particle(parent) ;
402 part->SetBit(kKeepBit);
403 parent = part->GetFirstMother() ;
407 if ( lostenergy != 0 ) { // Track is inside the crystal and deposits some energy
408 xyze[3] = gMC->TrackTime() ;
410 gMC->CurrentVolOffID(10, moduleNumber) ; // get the PHOS module number ;
413 gMC->CurrentVolOffID(3, strip);
415 gMC->CurrentVolOffID(2, cell);
417 Int_t row = 1 + GetGeometry()->GetNZ() - strip % GetGeometry()->GetNZ() ;
418 Int_t col = (Int_t) TMath::Ceil((Double_t) strip/GetGeometry()->GetNZ()) -1 ;
420 absid = (moduleNumber-1)*GetGeometry()->GetNCristalsInModule() +
421 row + (col*GetGeometry()->GetEMCAGeometry()->GetNCellsInStrip() + cell-1)*GetGeometry()->GetNZ() ;
423 gMC->Gmtod(global, local, 1) ;
425 //Calculates the light yield, the number of photns produced in the
427 Float_t lightYield = gRandom->Poisson(fLightFactor * lostenergy *
428 exp(-fLightYieldAttenuation *
429 (local[1]+GetGeometry()->GetCrystalSize(1)/2.0 ))
431 //Calculates de energy deposited in the crystal
432 xyze[4] = fAPDFactor * lightYield ;
434 // add current hit to the hit list
435 //cout << "AliPHOSv1::StepManager " << primary << " " << tracknumber << endl ;
436 AddHit(fIshunt, primary,tracknumber, absid, xyze);
438 // fill the relevant QA Checkables
439 fQATotEner->Update( xyze[4] ) ; // total energy in PHOS
440 (static_cast<AliPHOSQAFloatCheckable*>((*fQATotEnerB)[moduleNumber-1]))->Update( xyze[4] ) ; // energy in this block
442 } // there is deposited energy
443 } // we are inside a PHOS Xtal
447 //____________________________________________________________________________
448 void AliPHOSv1::CPVDigitize (TLorentzVector p, Float_t *zxhit, Int_t moduleNumber, TClonesArray *cpvDigits)
450 // ------------------------------------------------------------------------
451 // Digitize one CPV hit:
452 // On input take exact 4-momentum p and position zxhit of the hit,
453 // find the pad response around this hit and
454 // put the amplitudes in the pads into array digits
456 // Author: Yuri Kharlov (after Serguei Sadovsky)
458 // ------------------------------------------------------------------------
460 const Float_t kCelWr = GetGeometry()->GetPadSizePhi()/2; // Distance between wires (2 wires above 1 pad)
461 const Float_t kDetR = 0.1; // Relative energy fluctuation in track for 100 e-
462 const Float_t kdEdx = 4.0; // Average energy loss in CPV;
463 const Int_t kNgamz = 5; // Ionization size in Z
464 const Int_t kNgamx = 9; // Ionization size in Phi
465 const Float_t kNoise = 0.03; // charge noise in one pad
469 // Just a reminder on axes notation in the CPV module:
470 // axis Z goes along the beam
471 // axis X goes across the beam in the module plane
472 // axis Y is a normal to the module plane showing from the IP
474 Float_t hitX = zxhit[0];
475 Float_t hitZ =-zxhit[1];
478 Float_t pNorm = p.Py();
479 Float_t eloss = kdEdx;
481 // cout << "CPVDigitize: YVK : "<<hitX<<" "<<hitZ<<" | "<<pX<<" "<<pZ<<" "<<pNorm<<endl;
483 Float_t dZY = pZ/pNorm * GetGeometry()->GetCPVGasThickness();
484 Float_t dXY = pX/pNorm * GetGeometry()->GetCPVGasThickness();
485 gRandom->Rannor(rnor1,rnor2);
486 eloss *= (1 + kDetR*rnor1) *
487 TMath::Sqrt((1 + ( pow(dZY,2) + pow(dXY,2) ) / pow(GetGeometry()->GetCPVGasThickness(),2)));
488 Float_t zhit1 = hitZ + GetGeometry()->GetCPVActiveSize(1)/2 - dZY/2;
489 Float_t xhit1 = hitX + GetGeometry()->GetCPVActiveSize(0)/2 - dXY/2;
490 Float_t zhit2 = zhit1 + dZY;
491 Float_t xhit2 = xhit1 + dXY;
493 Int_t iwht1 = (Int_t) (xhit1 / kCelWr); // wire (x) coordinate "in"
494 Int_t iwht2 = (Int_t) (xhit2 / kCelWr); // wire (x) coordinate "out"
498 if (iwht1==iwht2) { // incline 1-wire hit
500 zxe[0][0] = (zhit1 + zhit2 - dZY*0.57735) / 2;
501 zxe[1][0] = (iwht1 + 0.5) * kCelWr;
503 zxe[0][1] = (zhit1 + zhit2 + dZY*0.57735) / 2;
504 zxe[1][1] = (iwht1 + 0.5) * kCelWr;
507 else if (TMath::Abs(iwht1-iwht2) != 1) { // incline 3-wire hit
509 Int_t iwht3 = (iwht1 + iwht2) / 2;
510 Float_t xwht1 = (iwht1 + 0.5) * kCelWr; // wire 1
511 Float_t xwht2 = (iwht2 + 0.5) * kCelWr; // wire 2
512 Float_t xwht3 = (iwht3 + 0.5) * kCelWr; // wire 3
513 Float_t xwr13 = (xwht1 + xwht3) / 2; // center 13
514 Float_t xwr23 = (xwht2 + xwht3) / 2; // center 23
515 Float_t dxw1 = xhit1 - xwr13;
516 Float_t dxw2 = xhit2 - xwr23;
517 Float_t egm1 = TMath::Abs(dxw1) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
518 Float_t egm2 = TMath::Abs(dxw2) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
519 Float_t egm3 = kCelWr / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
520 zxe[0][0] = (dXY*(xwr13-xwht1)/dXY + zhit1 + zhit1) / 2;
522 zxe[2][0] = eloss * egm1;
523 zxe[0][1] = (dXY*(xwr23-xwht1)/dXY + zhit1 + zhit2) / 2;
525 zxe[2][1] = eloss * egm2;
526 zxe[0][2] = dXY*(xwht3-xwht1)/dXY + zhit1;
528 zxe[2][2] = eloss * egm3;
530 else { // incline 2-wire hit
532 Float_t xwht1 = (iwht1 + 0.5) * kCelWr;
533 Float_t xwht2 = (iwht2 + 0.5) * kCelWr;
534 Float_t xwr12 = (xwht1 + xwht2) / 2;
535 Float_t dxw1 = xhit1 - xwr12;
536 Float_t dxw2 = xhit2 - xwr12;
537 Float_t egm1 = TMath::Abs(dxw1) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) );
538 Float_t egm2 = TMath::Abs(dxw2) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) );
539 zxe[0][0] = (zhit1 + zhit2 - dZY*egm1) / 2;
541 zxe[2][0] = eloss * egm1;
542 zxe[0][1] = (zhit1 + zhit2 + dZY*egm2) / 2;
544 zxe[2][1] = eloss * egm2;
547 // Finite size of ionization region
549 Int_t nCellZ = GetGeometry()->GetNumberOfCPVPadsZ();
550 Int_t nCellX = GetGeometry()->GetNumberOfCPVPadsPhi();
551 Int_t nz3 = (kNgamz+1)/2;
552 Int_t nx3 = (kNgamx+1)/2;
553 cpvDigits->Expand(nIter*kNgamx*kNgamz);
554 TClonesArray &ldigits = *(static_cast<TClonesArray *>(cpvDigits));
556 for (Int_t iter=0; iter<nIter; iter++) {
558 Float_t zhit = zxe[0][iter];
559 Float_t xhit = zxe[1][iter];
560 Float_t qhit = zxe[2][iter];
561 Float_t zcell = zhit / GetGeometry()->GetPadSizeZ();
562 Float_t xcell = xhit / GetGeometry()->GetPadSizePhi();
563 if ( zcell<=0 || xcell<=0 ||
564 zcell>=nCellZ || xcell>=nCellX) return;
565 Int_t izcell = (Int_t) zcell;
566 Int_t ixcell = (Int_t) xcell;
567 Float_t zc = zcell - izcell - 0.5;
568 Float_t xc = xcell - ixcell - 0.5;
569 for (Int_t iz=1; iz<=kNgamz; iz++) {
570 Int_t kzg = izcell + iz - nz3;
571 if (kzg<=0 || kzg>nCellZ) continue;
572 Float_t zg = (Float_t)(iz-nz3) - zc;
573 for (Int_t ix=1; ix<=kNgamx; ix++) {
574 Int_t kxg = ixcell + ix - nx3;
575 if (kxg<=0 || kxg>nCellX) continue;
576 Float_t xg = (Float_t)(ix-nx3) - xc;
578 // Now calculate pad response
579 Float_t qpad = CPVPadResponseFunction(qhit,zg,xg);
580 qpad += kNoise*rnor2;
581 if (qpad<0) continue;
583 // Fill the array with pad response ID and amplitude
584 new(ldigits[cpvDigits->GetEntriesFast()]) AliPHOSCPVDigit(kxg,kzg,qpad);
590 //____________________________________________________________________________
591 Float_t AliPHOSv1::CPVPadResponseFunction(Float_t qhit, Float_t zhit, Float_t xhit) {
592 // ------------------------------------------------------------------------
593 // Calculate the amplitude in one CPV pad using the
594 // cumulative pad response function
595 // Author: Yuri Kharlov (after Serguei Sadovski)
597 // ------------------------------------------------------------------------
599 Double_t dz = GetGeometry()->GetPadSizeZ() / 2;
600 Double_t dx = GetGeometry()->GetPadSizePhi() / 2;
601 Double_t z = zhit * GetGeometry()->GetPadSizeZ();
602 Double_t x = xhit * GetGeometry()->GetPadSizePhi();
603 Double_t amplitude = qhit *
604 (CPVCumulPadResponse(z+dz,x+dx) - CPVCumulPadResponse(z+dz,x-dx) -
605 CPVCumulPadResponse(z-dz,x+dx) + CPVCumulPadResponse(z-dz,x-dx));
606 return (Float_t)amplitude;
609 //____________________________________________________________________________
610 Double_t AliPHOSv1::CPVCumulPadResponse(Double_t x, Double_t y) {
611 // ------------------------------------------------------------------------
612 // Cumulative pad response function
613 // It includes several terms from the CF decomposition in electrostatics
614 // Note: this cumulative function is wrong since omits some terms
615 // but the cell amplitude obtained with it is correct because
616 // these omitting terms cancel
617 // Author: Yuri Kharlov (after Serguei Sadovski)
619 // ------------------------------------------------------------------------
621 const Double_t kA=1.0;
622 const Double_t kB=0.7;
624 Double_t r2 = x*x + y*y;
626 Double_t cumulPRF = 0;
627 for (Int_t i=0; i<=4; i++) {
628 Double_t b1 = (2*i + 1) * kB;
629 cumulPRF += TMath::Power(-1,i) * TMath::ATan( xy / (b1*TMath::Sqrt(b1*b1 + r2)) );
631 cumulPRF *= kA/(2*TMath::Pi());