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 // --- AliRoot header files ---
48 #include "AliPHOSv1.h"
49 #include "AliPHOSHit.h"
50 #include "AliPHOSCPVDigit.h"
53 #include "AliPHOSGeometry.h"
54 #include "AliPHOSQAIntCheckable.h"
55 #include "AliPHOSQAFloatCheckable.h"
56 #include "AliPHOSQAMeanChecker.h"
60 //____________________________________________________________________________
61 AliPHOSv1::AliPHOSv1():
64 // default ctor: initialze data memebers
70 fLightYieldMean = 0. ;
71 fIntrinsicPINEfficiency = 0. ;
72 fLightYieldAttenuation = 0. ;
73 fRecalibrationFactor = 0. ;
74 fElectronsPerGeV = 0. ;
81 //____________________________________________________________________________
82 AliPHOSv1::AliPHOSv1(const char *name, const char *title):
87 // - fHits (the "normal" one), which retains the hits associated with
88 // the current primary particle being tracked
89 // (this array is reset after each primary has been tracked).
94 // We do not want to save in TreeH the raw hits
95 // But save the cumulated hits instead (need to create the branch myself)
96 // It is put in the Digit Tree because the TreeH is filled after each primary
97 // and the TreeD at the end of the event (branch is set in FinishEvent() ).
99 fHits= new TClonesArray("AliPHOSHit",1000) ;
100 gAlice->AddHitList(fHits) ;
104 fIshunt = 2 ; // All hits are associated with primary particles
106 //Photoelectron statistics:
107 // The light yield is a poissonian distribution of the number of
108 // photons created in the PbWo4 crystal, calculated using following formula
109 // NumberOfPhotons = EnergyLost * LightYieldMean* APDEfficiency *
110 // exp (-LightYieldAttenuation * DistanceToPINdiodeFromTheHit);
111 // LightYieldMean is parameter calculated to be over 47000 photons per GeV
112 // APDEfficiency is 0.02655
113 // k_0 is 0.0045 from Valery Antonenko
114 // The number of electrons created in the APD is
115 // NumberOfElectrons = APDGain * LightYield
116 // The APD Gain is 300
117 fLightYieldMean = 47000;
118 fIntrinsicPINEfficiency = 0.02655 ; //APD= 0.1875/0.1271 * 0.018 (PIN)
119 fLightYieldAttenuation = 0.0045 ;
120 fRecalibrationFactor = 13.418/ fLightYieldMean ;
121 fElectronsPerGeV = 2.77e+8 ;
123 fLightFactor = fLightYieldMean * fIntrinsicPINEfficiency ;
124 fAPDFactor = (fRecalibrationFactor/100.) * fAPDGain ;
127 Int_t nb = GetGeometry()->GetNModules() ;
130 fQAHitsMul = new AliPHOSQAIntCheckable("HitsM") ;
131 fQATotEner = new AliPHOSQAFloatCheckable("TotEn") ;
132 fQAHitsMulB = new TClonesArray("AliPHOSQAIntCheckable",nb) ;
133 fQAHitsMulB->SetOwner() ;
134 fQATotEnerB = new TClonesArray("AliPHOSQAFloatCheckable", nb);
135 fQATotEnerB->SetOwner() ;
138 for ( i = 0 ; i < nb ; i++ ) {
139 sprintf(tempo, "HitsMB%d", i+1) ;
140 new( (*fQAHitsMulB)[i]) AliPHOSQAIntCheckable(tempo) ;
141 sprintf(tempo, "TotEnB%d", i+1) ;
142 new( (*fQATotEnerB)[i] ) AliPHOSQAFloatCheckable(tempo) ;
145 AliPHOSQAMeanChecker * hmc = new AliPHOSQAMeanChecker("HitsMul", 100. ,25.) ;
146 AliPHOSQAMeanChecker * emc = new AliPHOSQAMeanChecker("TotEner", 10. ,5.) ;
147 AliPHOSQAMeanChecker * bhmc = new AliPHOSQAMeanChecker("HitsMulB", 100. ,5.) ;
148 AliPHOSQAMeanChecker * bemc = new AliPHOSQAMeanChecker("TotEnerB", 2. ,.5) ;
150 // associate checkables and checkers
151 fQAHitsMul->AddChecker(hmc) ;
152 fQATotEner->AddChecker(emc) ;
153 for ( i = 0 ; i < nb ; i++ ) {
154 (static_cast<AliPHOSQAIntCheckable*>((*fQAHitsMulB)[i]))->AddChecker(bhmc) ;
155 (static_cast<AliPHOSQAFloatCheckable*>((*fQATotEnerB)[i]))->AddChecker(bemc) ;
160 //____________________________________________________________________________
161 AliPHOSv1::~AliPHOSv1()
172 fQAHitsMulB->Delete() ;
177 fQATotEnerB->Delete() ;
183 //____________________________________________________________________________
184 void AliPHOSv1::AddHit(Int_t shunt, Int_t primary, Int_t tracknumber, Int_t Id, Float_t * hits)
186 // Add a hit to the hit list.
187 // A PHOS hit is the sum of all hits in a single crystal from one primary and within some time gate
192 Bool_t deja = kFALSE ;
193 AliPHOSGeometry * geom = GetGeometry() ;
195 newHit = new AliPHOSHit(shunt, primary, tracknumber, Id, hits) ;
197 for ( hitCounter = fNhits-1 ; hitCounter >= 0 && !deja ; hitCounter-- ) {
198 curHit = dynamic_cast<AliPHOSHit*>((*fHits)[hitCounter]) ;
199 if(curHit->GetPrimary() != primary) break ;
200 // We add hits with the same primary, while GEANT treats primaries succesively
201 if( *curHit == *newHit ) {
208 new((*fHits)[fNhits]) AliPHOSHit(*newHit) ;
209 // get the block Id number
211 geom->AbsToRelNumbering(Id, relid) ;
212 // and fill the relevant QA checkable (only if in PbW04)
213 if ( relid[1] == 0 ) {
214 fQAHitsMul->Update(1) ;
215 (static_cast<AliPHOSQAIntCheckable*>((*fQAHitsMulB)[relid[0]-1]))->Update(1) ;
223 //____________________________________________________________________________
224 void AliPHOSv1::FinishPrimary()
226 // called at the end of each track (primary) by AliRun
227 // hits are reset for each new track
228 // accumulate the total hit-multiplicity
230 // fQAHitsMul->Update( fHits->GetEntriesFast() ) ;
234 //____________________________________________________________________________
235 void AliPHOSv1::FinishEvent()
237 // called at the end of each event by AliRun
238 // accumulate the hit-multiplicity and total energy per block
239 // if the values have been updated check it
242 if ( fQATotEner->HasChanged() ) {
243 fQATotEner->CheckMe() ;
244 fQATotEner->Reset() ;
249 if ( fQAHitsMulB && fQATotEnerB ) {
250 for (i = 0 ; i < GetGeometry()->GetNModules() ; i++) {
251 AliPHOSQAIntCheckable * ci = static_cast<AliPHOSQAIntCheckable*>((*fQAHitsMulB)[i]) ;
252 AliPHOSQAFloatCheckable* cf = static_cast<AliPHOSQAFloatCheckable*>((*fQATotEnerB)[i]) ;
253 if ( ci->HasChanged() ) {
257 if ( cf->HasChanged() ) {
264 // check the total multiplicity
267 if ( fQAHitsMul->HasChanged() ) {
268 fQAHitsMul->CheckMe() ;
269 fQAHitsMul->Reset() ;
273 //____________________________________________________________________________
274 void AliPHOSv1::StepManager(void)
276 // Accumulates hits as long as the track stays in a single crystal or CPV gas Cell
278 Int_t relid[4] ; // (box, layer, row, column) indices
279 Int_t absid ; // absolute cell ID number
280 Float_t xyzte[5]={-1000.,-1000.,-1000.,0.,0.} ; // position wrt MRS, time and energy deposited
281 TLorentzVector pos ; // Lorentz vector of the track current position
284 Int_t tracknumber = gAlice->CurrentTrack() ;
285 Int_t primary = gAlice->GetPrimary( gAlice->CurrentTrack() );
286 TString name = GetGeometry()->GetName() ;
290 if( gMC->CurrentVolID(copy) == gMC->VolId("PCPQ") &&
291 (gMC->IsTrackEntering() ) &&
292 gMC->TrackCharge() != 0) {
294 gMC -> TrackPosition(pos);
296 Float_t xyzm[3], xyzd[3] ;
298 for (i=0; i<3; i++) xyzm[i] = pos[i];
299 gMC -> Gmtod (xyzm, xyzd, 1); // transform coordinate from master to daughter system
301 Float_t xyd[3]={0,0,0} ; //local position of the entering
306 // Current momentum of the hit's track in the local ref. system
307 TLorentzVector pmom ; //momentum of the particle initiated hit
308 gMC -> TrackMomentum(pmom);
309 Float_t pm[3], pd[3];
313 gMC -> Gmtod (pm, pd, 2); // transform 3-momentum from master to daughter system
318 // Digitize the current CPV hit:
320 // 1. find pad response and
321 gMC->CurrentVolOffID(3,moduleNumber);
324 TClonesArray *cpvDigits = new TClonesArray("AliPHOSCPVDigit",0); // array of digits for current hit
325 CPVDigitize(pmom,xyd,moduleNumber,cpvDigits);
330 Int_t idigit,ndigits;
332 // 2. go through the current digit list and sum digits in pads
334 ndigits = cpvDigits->GetEntriesFast();
335 for (idigit=0; idigit<ndigits-1; idigit++) {
336 AliPHOSCPVDigit *cpvDigit1 = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(idigit));
337 Float_t x1 = cpvDigit1->GetXpad() ;
338 Float_t z1 = cpvDigit1->GetYpad() ;
339 for (Int_t jdigit=idigit+1; jdigit<ndigits; jdigit++) {
340 AliPHOSCPVDigit *cpvDigit2 = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(jdigit));
341 Float_t x2 = cpvDigit2->GetXpad() ;
342 Float_t z2 = cpvDigit2->GetYpad() ;
343 if (x1==x2 && z1==z2) {
344 Float_t qsum = cpvDigit1->GetQpad() + cpvDigit2->GetQpad() ;
345 cpvDigit2->SetQpad(qsum) ;
346 cpvDigits->RemoveAt(idigit) ;
350 cpvDigits->Compress() ;
352 // 3. add digits to temporary hit list fTmpHits
354 ndigits = cpvDigits->GetEntriesFast();
355 for (idigit=0; idigit<ndigits; idigit++) {
356 AliPHOSCPVDigit *cpvDigit = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(idigit));
357 relid[0] = moduleNumber + 1 ; // CPV (or PHOS) module number
358 relid[1] =-1 ; // means CPV
359 relid[2] = cpvDigit->GetXpad() ; // column number of a pad
360 relid[3] = cpvDigit->GetYpad() ; // row number of a pad
362 // get the absolute Id number
363 GetGeometry()->RelToAbsNumbering(relid, absid) ;
365 // add current digit to the temporary hit list
367 xyzte[3] = gMC->TrackTime() ;
368 xyzte[4] = cpvDigit->GetQpad() ; // amplitude in a pad
369 primary = -1; // No need in primary for CPV
370 AddHit(fIshunt, primary, tracknumber, absid, xyzte);
372 if (cpvDigit->GetQpad() > 0.02) {
373 xmean += cpvDigit->GetQpad() * (cpvDigit->GetXpad() + 0.5);
374 zmean += cpvDigit->GetQpad() * (cpvDigit->GetYpad() + 0.5);
375 qsum += cpvDigit->GetQpad();
387 if(gMC->CurrentVolID(copy) == gMC->VolId("PXTL") ) { // We are inside a PBWO crystal
389 gMC->TrackPosition(pos) ;
394 Float_t global[3], local[3] ;
398 Float_t lostenergy = gMC->Edep();
400 //Put in the TreeK particle entering PHOS and all its parents
401 if ( gMC->IsTrackEntering() ){
403 gMC -> Gmtod (xyzte, xyzd, 1); // transform coordinate from master to daughter system
404 if (xyzd[1] > GetGeometry()->GetCrystalSize(1)/2-0.002 ||
405 xyzd[1] < -GetGeometry()->GetCrystalSize(1)/2+0.002) {
406 TParticle * part = 0 ;
407 Int_t parent = gAlice->CurrentTrack() ;
408 while ( parent != -1 ) {
409 part = gAlice->Particle(parent) ;
410 part->SetBit(kKeepBit);
411 parent = part->GetFirstMother() ;
415 if ( lostenergy != 0 ) { // Track is inside the crystal and deposits some energy
416 xyzte[3] = gMC->TrackTime() ;
418 gMC->CurrentVolOffID(10, moduleNumber) ; // get the PHOS module number ;
421 gMC->CurrentVolOffID(3, strip);
423 gMC->CurrentVolOffID(2, cell);
425 Int_t row = 1 + GetGeometry()->GetNZ() - strip % GetGeometry()->GetNZ() ;
426 Int_t col = (Int_t) TMath::Ceil((Double_t) strip/GetGeometry()->GetNZ()) -1 ;
428 absid = (moduleNumber-1)*GetGeometry()->GetNCristalsInModule() +
429 row + (col*GetGeometry()->GetEMCAGeometry()->GetNCellsInStrip() + cell-1)*GetGeometry()->GetNZ() ;
431 gMC->Gmtod(global, local, 1) ;
433 //Calculates the light yield, the number of photons produced in the
435 Float_t lightYield = gRandom->Poisson(fLightFactor * lostenergy *
436 exp(-fLightYieldAttenuation *
437 (local[1]+GetGeometry()->GetCrystalSize(1)/2.0 ))
440 //Calculates de energy deposited in the crystal
441 xyzte[4] = fAPDFactor * lightYield ;
443 // add current hit to the hit list
444 // Info("StepManager","%d %d", primary, tracknumber) ;
445 AddHit(fIshunt, primary,tracknumber, absid, xyzte);
447 // fill the relevant QA Checkables
448 fQATotEner->Update( xyzte[4] ) ; // total energy in PHOS
449 (static_cast<AliPHOSQAFloatCheckable*>((*fQATotEnerB)[moduleNumber-1]))->Update( xyzte[4] ) ; // energy in this block
451 } // there is deposited energy
452 } // we are inside a PHOS Xtal
456 //____________________________________________________________________________
457 void AliPHOSv1::CPVDigitize (TLorentzVector p, Float_t *zxhit, Int_t moduleNumber, TClonesArray *cpvDigits)
459 // ------------------------------------------------------------------------
460 // Digitize one CPV hit:
461 // On input take exact 4-momentum p and position zxhit of the hit,
462 // find the pad response around this hit and
463 // put the amplitudes in the pads into array digits
465 // Author: Yuri Kharlov (after Serguei Sadovsky)
467 // ------------------------------------------------------------------------
469 const Float_t kCelWr = GetGeometry()->GetPadSizePhi()/2; // Distance between wires (2 wires above 1 pad)
470 const Float_t kDetR = 0.1; // Relative energy fluctuation in track for 100 e-
471 const Float_t kdEdx = 4.0; // Average energy loss in CPV;
472 const Int_t kNgamz = 5; // Ionization size in Z
473 const Int_t kNgamx = 9; // Ionization size in Phi
474 const Float_t kNoise = 0.03; // charge noise in one pad
478 // Just a reminder on axes notation in the CPV module:
479 // axis Z goes along the beam
480 // axis X goes across the beam in the module plane
481 // axis Y is a normal to the module plane showing from the IP
483 Float_t hitX = zxhit[0];
484 Float_t hitZ =-zxhit[1];
487 Float_t pNorm = p.Py();
488 Float_t eloss = kdEdx;
490 //Info("CPVDigitize", "YVK : %f %f | %f %f %d", hitX, hitZ, pX, pZ, pNorm) ;
492 Float_t dZY = pZ/pNorm * GetGeometry()->GetCPVGasThickness();
493 Float_t dXY = pX/pNorm * GetGeometry()->GetCPVGasThickness();
494 gRandom->Rannor(rnor1,rnor2);
495 eloss *= (1 + kDetR*rnor1) *
496 TMath::Sqrt((1 + ( pow(dZY,2) + pow(dXY,2) ) / pow(GetGeometry()->GetCPVGasThickness(),2)));
497 Float_t zhit1 = hitZ + GetGeometry()->GetCPVActiveSize(1)/2 - dZY/2;
498 Float_t xhit1 = hitX + GetGeometry()->GetCPVActiveSize(0)/2 - dXY/2;
499 Float_t zhit2 = zhit1 + dZY;
500 Float_t xhit2 = xhit1 + dXY;
502 Int_t iwht1 = (Int_t) (xhit1 / kCelWr); // wire (x) coordinate "in"
503 Int_t iwht2 = (Int_t) (xhit2 / kCelWr); // wire (x) coordinate "out"
507 if (iwht1==iwht2) { // incline 1-wire hit
509 zxe[0][0] = (zhit1 + zhit2 - dZY*0.57735) / 2;
510 zxe[1][0] = (iwht1 + 0.5) * kCelWr;
512 zxe[0][1] = (zhit1 + zhit2 + dZY*0.57735) / 2;
513 zxe[1][1] = (iwht1 + 0.5) * kCelWr;
516 else if (TMath::Abs(iwht1-iwht2) != 1) { // incline 3-wire hit
518 Int_t iwht3 = (iwht1 + iwht2) / 2;
519 Float_t xwht1 = (iwht1 + 0.5) * kCelWr; // wire 1
520 Float_t xwht2 = (iwht2 + 0.5) * kCelWr; // wire 2
521 Float_t xwht3 = (iwht3 + 0.5) * kCelWr; // wire 3
522 Float_t xwr13 = (xwht1 + xwht3) / 2; // center 13
523 Float_t xwr23 = (xwht2 + xwht3) / 2; // center 23
524 Float_t dxw1 = xhit1 - xwr13;
525 Float_t dxw2 = xhit2 - xwr23;
526 Float_t egm1 = TMath::Abs(dxw1) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
527 Float_t egm2 = TMath::Abs(dxw2) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
528 Float_t egm3 = kCelWr / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
529 zxe[0][0] = (dXY*(xwr13-xwht1)/dXY + zhit1 + zhit1) / 2;
531 zxe[2][0] = eloss * egm1;
532 zxe[0][1] = (dXY*(xwr23-xwht1)/dXY + zhit1 + zhit2) / 2;
534 zxe[2][1] = eloss * egm2;
535 zxe[0][2] = dXY*(xwht3-xwht1)/dXY + zhit1;
537 zxe[2][2] = eloss * egm3;
539 else { // incline 2-wire hit
541 Float_t xwht1 = (iwht1 + 0.5) * kCelWr;
542 Float_t xwht2 = (iwht2 + 0.5) * kCelWr;
543 Float_t xwr12 = (xwht1 + xwht2) / 2;
544 Float_t dxw1 = xhit1 - xwr12;
545 Float_t dxw2 = xhit2 - xwr12;
546 Float_t egm1 = TMath::Abs(dxw1) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) );
547 Float_t egm2 = TMath::Abs(dxw2) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) );
548 zxe[0][0] = (zhit1 + zhit2 - dZY*egm1) / 2;
550 zxe[2][0] = eloss * egm1;
551 zxe[0][1] = (zhit1 + zhit2 + dZY*egm2) / 2;
553 zxe[2][1] = eloss * egm2;
556 // Finite size of ionization region
558 Int_t nCellZ = GetGeometry()->GetNumberOfCPVPadsZ();
559 Int_t nCellX = GetGeometry()->GetNumberOfCPVPadsPhi();
560 Int_t nz3 = (kNgamz+1)/2;
561 Int_t nx3 = (kNgamx+1)/2;
562 cpvDigits->Expand(nIter*kNgamx*kNgamz);
563 TClonesArray &ldigits = *(static_cast<TClonesArray *>(cpvDigits));
565 for (Int_t iter=0; iter<nIter; iter++) {
567 Float_t zhit = zxe[0][iter];
568 Float_t xhit = zxe[1][iter];
569 Float_t qhit = zxe[2][iter];
570 Float_t zcell = zhit / GetGeometry()->GetPadSizeZ();
571 Float_t xcell = xhit / GetGeometry()->GetPadSizePhi();
572 if ( zcell<=0 || xcell<=0 ||
573 zcell>=nCellZ || xcell>=nCellX) return;
574 Int_t izcell = (Int_t) zcell;
575 Int_t ixcell = (Int_t) xcell;
576 Float_t zc = zcell - izcell - 0.5;
577 Float_t xc = xcell - ixcell - 0.5;
578 for (Int_t iz=1; iz<=kNgamz; iz++) {
579 Int_t kzg = izcell + iz - nz3;
580 if (kzg<=0 || kzg>nCellZ) continue;
581 Float_t zg = (Float_t)(iz-nz3) - zc;
582 for (Int_t ix=1; ix<=kNgamx; ix++) {
583 Int_t kxg = ixcell + ix - nx3;
584 if (kxg<=0 || kxg>nCellX) continue;
585 Float_t xg = (Float_t)(ix-nx3) - xc;
587 // Now calculate pad response
588 Float_t qpad = CPVPadResponseFunction(qhit,zg,xg);
589 qpad += kNoise*rnor2;
590 if (qpad<0) continue;
592 // Fill the array with pad response ID and amplitude
593 new(ldigits[cpvDigits->GetEntriesFast()]) AliPHOSCPVDigit(kxg,kzg,qpad);
599 //____________________________________________________________________________
600 Float_t AliPHOSv1::CPVPadResponseFunction(Float_t qhit, Float_t zhit, Float_t xhit) {
601 // ------------------------------------------------------------------------
602 // Calculate the amplitude in one CPV pad using the
603 // cumulative pad response function
604 // Author: Yuri Kharlov (after Serguei Sadovski)
606 // ------------------------------------------------------------------------
608 Double_t dz = GetGeometry()->GetPadSizeZ() / 2;
609 Double_t dx = GetGeometry()->GetPadSizePhi() / 2;
610 Double_t z = zhit * GetGeometry()->GetPadSizeZ();
611 Double_t x = xhit * GetGeometry()->GetPadSizePhi();
612 Double_t amplitude = qhit *
613 (CPVCumulPadResponse(z+dz,x+dx) - CPVCumulPadResponse(z+dz,x-dx) -
614 CPVCumulPadResponse(z-dz,x+dx) + CPVCumulPadResponse(z-dz,x-dx));
615 return (Float_t)amplitude;
618 //____________________________________________________________________________
619 Double_t AliPHOSv1::CPVCumulPadResponse(Double_t x, Double_t y) {
620 // ------------------------------------------------------------------------
621 // Cumulative pad response function
622 // It includes several terms from the CF decomposition in electrostatics
623 // Note: this cumulative function is wrong since omits some terms
624 // but the cell amplitude obtained with it is correct because
625 // these omitting terms cancel
626 // Author: Yuri Kharlov (after Serguei Sadovski)
628 // ------------------------------------------------------------------------
630 const Double_t kA=1.0;
631 const Double_t kB=0.7;
633 Double_t r2 = x*x + y*y;
635 Double_t cumulPRF = 0;
636 for (Int_t i=0; i<=4; i++) {
637 Double_t b1 = (2*i + 1) * kB;
638 cumulPRF += TMath::Power(-1,i) * TMath::ATan( xy / (b1*TMath::Sqrt(b1*b1 + r2)) );
640 cumulPRF *= kA/(2*TMath::Pi());