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18 /* History of cvs commits:
21 * Revision 1.104 2005/05/28 14:19:05 schutz
22 * Compilation warnings fixed by T.P.
26 //_________________________________________________________________________
27 // Implementation version v1 of PHOS Manager class
30 // Layout EMC + CPV has name IHEP:
31 // Produces hits for CPV, cumulated hits
34 //*-- Author: Yves Schutz (SUBATECH)
37 // --- ROOT system ---
38 #include <TParticle.h>
39 #include <TVirtualMC.h>
41 // --- Standard library ---
44 // --- AliRoot header files ---
45 #include "AliPHOSCPVDigit.h"
46 #include "AliPHOSGeometry.h"
47 #include "AliPHOSHit.h"
48 #include "AliPHOSv1.h"
54 //____________________________________________________________________________
55 AliPHOSv1::AliPHOSv1():
57 fIntrinsicPINEfficiency(0.),
58 fLightYieldAttenuation(0.),
59 fRecalibrationFactor(0.),
68 //____________________________________________________________________________
69 AliPHOSv1::AliPHOSv1(const char *name, const char *title):
70 AliPHOSv0(name,title),
72 fIntrinsicPINEfficiency(0.),
73 fLightYieldAttenuation(0.),
74 fRecalibrationFactor(0.),
82 // - fHits (the "normal" one), which retains the hits associated with
83 // the current primary particle being tracked
84 // (this array is reset after each primary has been tracked).
89 // We do not want to save in TreeH the raw hits
90 // But save the cumulated hits instead (need to create the branch myself)
91 // It is put in the Digit Tree because the TreeH is filled after each primary
92 // and the TreeD at the end of the event (branch is set in FinishEvent() ).
94 fHits= new TClonesArray("AliPHOSHit",1000) ;
95 gAlice->GetMCApp()->AddHitList(fHits) ;
99 fIshunt = 2 ; // All hits are associated with primary particles
101 //Photoelectron statistics:
102 // The light yield is a poissonian distribution of the number of
103 // photons created in the PbWo4 crystal, calculated using following formula
104 // NumberOfPhotons = EnergyLost * LightYieldMean* APDEfficiency *
105 // exp (-LightYieldAttenuation * DistanceToPINdiodeFromTheHit);
106 // LightYieldMean is parameter calculated to be over 47000 photons per GeV
107 // APDEfficiency is 0.02655
108 // k_0 is 0.0045 from Valery Antonenko
109 // The number of electrons created in the APD is
110 // NumberOfElectrons = APDGain * LightYield
111 // The APD Gain is 300
112 fLightYieldMean = 47000;
113 fIntrinsicPINEfficiency = 0.02655 ; //APD= 0.1875/0.1271 * 0.018 (PIN)
114 fLightYieldAttenuation = 0.0045 ;
115 fRecalibrationFactor = 13.418/ fLightYieldMean ;
116 fElectronsPerGeV = 2.77e+8 ;
118 fLightFactor = fLightYieldMean * fIntrinsicPINEfficiency ;
119 fAPDFactor = (fRecalibrationFactor/100.) * fAPDGain ;
122 AliPHOSv1::AliPHOSv1(AliPHOSv1 & phos) :
125 fIntrinsicPINEfficiency(0.),
126 fLightYieldAttenuation(0.),
127 fRecalibrationFactor(0.),
128 fElectronsPerGeV(0.),
133 //Copy ctor. Can be wrong.
138 //____________________________________________________________________________
139 AliPHOSv1::~AliPHOSv1()
149 //____________________________________________________________________________
150 void AliPHOSv1::Copy(TObject & base)const
152 TObject::Copy(base) ;
153 AliPHOSv0::Copy(base) ;
154 AliPHOSv1 &phos = static_cast<AliPHOSv1 &>(base);
155 phos.fLightYieldMean = fLightYieldMean ;
156 phos.fIntrinsicPINEfficiency = fIntrinsicPINEfficiency ;
157 phos.fLightYieldAttenuation = fLightYieldAttenuation ;
158 phos.fRecalibrationFactor = fRecalibrationFactor ;
159 phos.fElectronsPerGeV = fElectronsPerGeV ;
160 phos.fAPDGain = fAPDGain ;
161 phos.fLightFactor = fLightFactor ;
162 phos.fAPDFactor = fAPDFactor ;
165 //____________________________________________________________________________
166 void AliPHOSv1::AddHit(Int_t shunt, Int_t primary, Int_t Id, Float_t * hits)
168 // Add a hit to the hit list.
169 // A PHOS hit is the sum of all hits in a single crystal from one primary and within some time gate
174 Bool_t deja = kFALSE ;
175 AliPHOSGeometry * geom = GetGeometry() ;
177 newHit = new AliPHOSHit(shunt, primary, Id, hits) ;
179 for ( hitCounter = fNhits-1 ; hitCounter >= 0 && !deja ; hitCounter-- ) {
180 curHit = dynamic_cast<AliPHOSHit*>((*fHits)[hitCounter]) ;
181 if(curHit->GetPrimary() != primary) break ;
182 // We add hits with the same primary, while GEANT treats primaries succesively
183 if( *curHit == *newHit ) {
190 new((*fHits)[fNhits]) AliPHOSHit(*newHit) ;
191 // get the block Id number
193 geom->AbsToRelNumbering(Id, relid) ;
201 //____________________________________________________________________________
202 void AliPHOSv1::FinishPrimary()
204 // called at the end of each track (primary) by AliRun
205 // hits are reset for each new track
206 // accumulate the total hit-multiplicity
210 //____________________________________________________________________________
211 void AliPHOSv1::FinishEvent()
213 // called at the end of each event by AliRun
214 // accumulate the hit-multiplicity and total energy per block
215 // if the values have been updated check it
217 AliDetector::FinishEvent();
219 //____________________________________________________________________________
220 void AliPHOSv1::StepManager(void)
222 // Accumulates hits as long as the track stays in a single crystal or CPV gas Cell
224 Int_t relid[4] ; // (box, layer, row, column) indices
225 Int_t absid ; // absolute cell ID number
226 Float_t xyzte[5]={-1000.,-1000.,-1000.,0.,0.} ; // position wrt MRS, time and energy deposited
227 TLorentzVector pos ; // Lorentz vector of the track current position
230 TString name = GetGeometry()->GetName() ;
234 static Int_t idPCPQ = gMC->VolId("PCPQ");
235 if( gMC->CurrentVolID(copy) == idPCPQ &&
236 (gMC->IsTrackEntering() ) &&
237 gMC->TrackCharge() != 0) {
239 gMC -> TrackPosition(pos);
241 Float_t xyzm[3], xyzd[3] ;
243 for (i=0; i<3; i++) xyzm[i] = pos[i];
244 gMC -> Gmtod (xyzm, xyzd, 1); // transform coordinate from master to daughter system
246 Float_t xyd[3]={0,0,0} ; //local position of the entering
251 // Current momentum of the hit's track in the local ref. system
252 TLorentzVector pmom ; //momentum of the particle initiated hit
253 gMC -> TrackMomentum(pmom);
254 Float_t pm[3], pd[3];
258 gMC -> Gmtod (pm, pd, 2); // transform 3-momentum from master to daughter system
263 // Digitize the current CPV hit:
265 // 1. find pad response and
266 gMC->CurrentVolOffID(3,moduleNumber);
269 TClonesArray *cpvDigits = new TClonesArray("AliPHOSCPVDigit",0); // array of digits for current hit
270 CPVDigitize(pmom,xyd,cpvDigits);
275 Int_t idigit,ndigits;
277 // 2. go through the current digit list and sum digits in pads
279 ndigits = cpvDigits->GetEntriesFast();
280 for (idigit=0; idigit<ndigits-1; idigit++) {
281 AliPHOSCPVDigit *cpvDigit1 = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(idigit));
282 Float_t x1 = cpvDigit1->GetXpad() ;
283 Float_t z1 = cpvDigit1->GetYpad() ;
284 for (Int_t jdigit=idigit+1; jdigit<ndigits; jdigit++) {
285 AliPHOSCPVDigit *cpvDigit2 = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(jdigit));
286 Float_t x2 = cpvDigit2->GetXpad() ;
287 Float_t z2 = cpvDigit2->GetYpad() ;
288 if (x1==x2 && z1==z2) {
289 Float_t qsum = cpvDigit1->GetQpad() + cpvDigit2->GetQpad() ;
290 cpvDigit2->SetQpad(qsum) ;
291 cpvDigits->RemoveAt(idigit) ;
295 cpvDigits->Compress() ;
297 // 3. add digits to temporary hit list fTmpHits
299 ndigits = cpvDigits->GetEntriesFast();
300 for (idigit=0; idigit<ndigits; idigit++) {
301 AliPHOSCPVDigit *cpvDigit = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(idigit));
302 relid[0] = moduleNumber + 1 ; // CPV (or PHOS) module number
303 relid[1] =-1 ; // means CPV
304 relid[2] = cpvDigit->GetXpad() ; // column number of a pad
305 relid[3] = cpvDigit->GetYpad() ; // row number of a pad
307 // get the absolute Id number
308 GetGeometry()->RelToAbsNumbering(relid, absid) ;
310 // add current digit to the temporary hit list
312 xyzte[3] = gMC->TrackTime() ;
313 xyzte[4] = cpvDigit->GetQpad() ; // amplitude in a pad
315 Int_t primary = gAlice->GetMCApp()->GetPrimary( gAlice->GetMCApp()->GetCurrentTrackNumber() );
316 AddHit(fIshunt, primary, absid, xyzte);
318 if (cpvDigit->GetQpad() > 0.02) {
319 xmean += cpvDigit->GetQpad() * (cpvDigit->GetXpad() + 0.5);
320 zmean += cpvDigit->GetQpad() * (cpvDigit->GetYpad() + 0.5);
321 qsum += cpvDigit->GetQpad();
332 static Int_t idPXTL = gMC->VolId("PXTL");
333 if(gMC->CurrentVolID(copy) == idPXTL ) { // We are inside a PBWO crystal
335 gMC->TrackPosition(pos) ;
340 Float_t global[3], local[3] ;
344 Float_t lostenergy = gMC->Edep();
346 //Put in the TreeK particle entering PHOS and all its parents
347 if ( gMC->IsTrackEntering() ){
349 gMC -> Gmtod (xyzte, xyzd, 1); // transform coordinate from master to daughter system
350 if (xyzd[1] < -GetGeometry()->GetCrystalSize(1)/2.+0.1){ //Entered close to forward surface
351 Int_t parent = gAlice->GetMCApp()->GetCurrentTrackNumber() ;
352 TParticle * part = gAlice->GetMCApp()->Particle(parent) ;
353 Float_t vert[3],vertd[3] ;
357 gMC -> Gmtod (vert, vertd, 1); // transform coordinate from master to daughter system
358 if(vertd[1]<-GetGeometry()->GetCrystalSize(1)/2.-0.1){ //Particle is created in foront of PHOS
359 //0.1 to get rid of numerical errors
360 part->SetBit(kKeepBit);
361 while ( parent != -1 ) {
362 part = gAlice->GetMCApp()->Particle(parent) ;
363 part->SetBit(kKeepBit);
364 parent = part->GetFirstMother() ;
369 if ( lostenergy != 0 ) { // Track is inside the crystal and deposits some energy
370 xyzte[3] = gMC->TrackTime() ;
372 gMC->CurrentVolOffID(10, moduleNumber) ; // get the PHOS module number ;
375 gMC->CurrentVolOffID(3, strip);
377 gMC->CurrentVolOffID(2, cell);
379 Int_t row = 1 + GetGeometry()->GetNZ() - strip % GetGeometry()->GetNZ() ;
380 Int_t col = (Int_t) TMath::Ceil((Double_t) strip/GetGeometry()->GetNZ()) -1 ;
382 absid = (moduleNumber-1)*GetGeometry()->GetNCristalsInModule() +
383 row + (col*GetGeometry()->GetEMCAGeometry()->GetNCellsInStrip() + cell-1)*GetGeometry()->GetNZ() ;
385 gMC->Gmtod(global, local, 1) ;
387 //Calculates the light yield, the number of photons produced in the
389 Float_t lightYield = gRandom->Poisson(fLightFactor * lostenergy *
390 exp(-fLightYieldAttenuation *
391 (local[1]+GetGeometry()->GetCrystalSize(1)/2.0 ))
394 //Calculates de energy deposited in the crystal
395 xyzte[4] = fAPDFactor * lightYield ;
399 primary = gAlice->GetMCApp()->GetCurrentTrackNumber() ;
400 TParticle * part = gAlice->GetMCApp()->Particle(primary) ;
401 while ( !part->TestBit(kKeepBit) ) {
402 primary = part->GetFirstMother() ;
404 primary = gAlice->GetMCApp()->GetPrimary( gAlice->GetMCApp()->GetCurrentTrackNumber() );
405 break ; //there is a possibility that particle passed e.g. thermal isulator and hits a side
406 //surface of the crystal. In this case it may have no primary at all.
407 //We can not easily separate this case from the case when this is part of the shower,
408 //developed in the neighboring crystal.
410 part = gAlice->GetMCApp()->Particle(primary) ;
414 primary = gAlice->GetMCApp()->GetPrimary( gAlice->GetMCApp()->GetCurrentTrackNumber() );
418 // add current hit to the hit list
419 // Info("StepManager","%d %d", primary, tracknumber) ;
420 AddHit(fIshunt, primary, absid, xyzte);
422 } // there is deposited energy
423 } // we are inside a PHOS Xtal
427 //____________________________________________________________________________
428 void AliPHOSv1::CPVDigitize (TLorentzVector p, Float_t *zxhit, TClonesArray *cpvDigits)
430 // ------------------------------------------------------------------------
431 // Digitize one CPV hit:
432 // On input take exact 4-momentum p and position zxhit of the hit,
433 // find the pad response around this hit and
434 // put the amplitudes in the pads into array digits
436 // Author: Yuri Kharlov (after Serguei Sadovsky)
438 // ------------------------------------------------------------------------
440 const Float_t kCelWr = GetGeometry()->GetPadSizePhi()/2; // Distance between wires (2 wires above 1 pad)
441 const Float_t kDetR = 0.1; // Relative energy fluctuation in track for 100 e-
442 const Float_t kdEdx = 4.0; // Average energy loss in CPV;
443 const Int_t kNgamz = 5; // Ionization size in Z
444 const Int_t kNgamx = 9; // Ionization size in Phi
445 const Float_t kNoise = 0.03; // charge noise in one pad
449 // Just a reminder on axes notation in the CPV module:
450 // axis Z goes along the beam
451 // axis X goes across the beam in the module plane
452 // axis Y is a normal to the module plane showing from the IP
454 Float_t hitX = zxhit[0];
455 Float_t hitZ =-zxhit[1];
458 Float_t pNorm = p.Py();
459 Float_t eloss = kdEdx;
461 //Info("CPVDigitize", "YVK : %f %f | %f %f %d", hitX, hitZ, pX, pZ, pNorm) ;
463 Float_t dZY = pZ/pNorm * GetGeometry()->GetCPVGasThickness();
464 Float_t dXY = pX/pNorm * GetGeometry()->GetCPVGasThickness();
465 gRandom->Rannor(rnor1,rnor2);
466 eloss *= (1 + kDetR*rnor1) *
467 TMath::Sqrt((1 + ( pow(dZY,2) + pow(dXY,2) ) / pow(GetGeometry()->GetCPVGasThickness(),2)));
468 Float_t zhit1 = hitZ + GetGeometry()->GetCPVActiveSize(1)/2 - dZY/2;
469 Float_t xhit1 = hitX + GetGeometry()->GetCPVActiveSize(0)/2 - dXY/2;
470 Float_t zhit2 = zhit1 + dZY;
471 Float_t xhit2 = xhit1 + dXY;
473 Int_t iwht1 = (Int_t) (xhit1 / kCelWr); // wire (x) coordinate "in"
474 Int_t iwht2 = (Int_t) (xhit2 / kCelWr); // wire (x) coordinate "out"
478 if (iwht1==iwht2) { // incline 1-wire hit
480 zxe[0][0] = (zhit1 + zhit2 - dZY*0.57735) / 2;
481 zxe[1][0] = (iwht1 + 0.5) * kCelWr;
483 zxe[0][1] = (zhit1 + zhit2 + dZY*0.57735) / 2;
484 zxe[1][1] = (iwht1 + 0.5) * kCelWr;
487 else if (TMath::Abs(iwht1-iwht2) != 1) { // incline 3-wire hit
489 Int_t iwht3 = (iwht1 + iwht2) / 2;
490 Float_t xwht1 = (iwht1 + 0.5) * kCelWr; // wire 1
491 Float_t xwht2 = (iwht2 + 0.5) * kCelWr; // wire 2
492 Float_t xwht3 = (iwht3 + 0.5) * kCelWr; // wire 3
493 Float_t xwr13 = (xwht1 + xwht3) / 2; // center 13
494 Float_t xwr23 = (xwht2 + xwht3) / 2; // center 23
495 Float_t dxw1 = xhit1 - xwr13;
496 Float_t dxw2 = xhit2 - xwr23;
497 Float_t egm1 = TMath::Abs(dxw1) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
498 Float_t egm2 = TMath::Abs(dxw2) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
499 Float_t egm3 = kCelWr / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
500 zxe[0][0] = (dXY*(xwr13-xwht1)/dXY + zhit1 + zhit1) / 2;
502 zxe[2][0] = eloss * egm1;
503 zxe[0][1] = (dXY*(xwr23-xwht1)/dXY + zhit1 + zhit2) / 2;
505 zxe[2][1] = eloss * egm2;
506 zxe[0][2] = dXY*(xwht3-xwht1)/dXY + zhit1;
508 zxe[2][2] = eloss * egm3;
510 else { // incline 2-wire hit
512 Float_t xwht1 = (iwht1 + 0.5) * kCelWr;
513 Float_t xwht2 = (iwht2 + 0.5) * kCelWr;
514 Float_t xwr12 = (xwht1 + xwht2) / 2;
515 Float_t dxw1 = xhit1 - xwr12;
516 Float_t dxw2 = xhit2 - xwr12;
517 Float_t egm1 = TMath::Abs(dxw1) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) );
518 Float_t egm2 = TMath::Abs(dxw2) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) );
519 zxe[0][0] = (zhit1 + zhit2 - dZY*egm1) / 2;
521 zxe[2][0] = eloss * egm1;
522 zxe[0][1] = (zhit1 + zhit2 + dZY*egm2) / 2;
524 zxe[2][1] = eloss * egm2;
527 // Finite size of ionization region
529 Int_t nCellZ = GetGeometry()->GetNumberOfCPVPadsZ();
530 Int_t nCellX = GetGeometry()->GetNumberOfCPVPadsPhi();
531 Int_t nz3 = (kNgamz+1)/2;
532 Int_t nx3 = (kNgamx+1)/2;
533 cpvDigits->Expand(nIter*kNgamx*kNgamz);
534 TClonesArray &ldigits = *(static_cast<TClonesArray *>(cpvDigits));
536 for (Int_t iter=0; iter<nIter; iter++) {
538 Float_t zhit = zxe[0][iter];
539 Float_t xhit = zxe[1][iter];
540 Float_t qhit = zxe[2][iter];
541 Float_t zcell = zhit / GetGeometry()->GetPadSizeZ();
542 Float_t xcell = xhit / GetGeometry()->GetPadSizePhi();
543 if ( zcell<=0 || xcell<=0 ||
544 zcell>=nCellZ || xcell>=nCellX) return;
545 Int_t izcell = (Int_t) zcell;
546 Int_t ixcell = (Int_t) xcell;
547 Float_t zc = zcell - izcell - 0.5;
548 Float_t xc = xcell - ixcell - 0.5;
549 for (Int_t iz=1; iz<=kNgamz; iz++) {
550 Int_t kzg = izcell + iz - nz3;
551 if (kzg<=0 || kzg>nCellZ) continue;
552 Float_t zg = (Float_t)(iz-nz3) - zc;
553 for (Int_t ix=1; ix<=kNgamx; ix++) {
554 Int_t kxg = ixcell + ix - nx3;
555 if (kxg<=0 || kxg>nCellX) continue;
556 Float_t xg = (Float_t)(ix-nx3) - xc;
558 // Now calculate pad response
559 Float_t qpad = CPVPadResponseFunction(qhit,zg,xg);
560 qpad += kNoise*rnor2;
561 if (qpad<0) continue;
563 // Fill the array with pad response ID and amplitude
564 new(ldigits[cpvDigits->GetEntriesFast()]) AliPHOSCPVDigit(kxg,kzg,qpad);
570 //____________________________________________________________________________
571 Float_t AliPHOSv1::CPVPadResponseFunction(Float_t qhit, Float_t zhit, Float_t xhit) {
572 // ------------------------------------------------------------------------
573 // Calculate the amplitude in one CPV pad using the
574 // cumulative pad response function
575 // Author: Yuri Kharlov (after Serguei Sadovski)
577 // ------------------------------------------------------------------------
579 Double_t dz = GetGeometry()->GetPadSizeZ() / 2;
580 Double_t dx = GetGeometry()->GetPadSizePhi() / 2;
581 Double_t z = zhit * GetGeometry()->GetPadSizeZ();
582 Double_t x = xhit * GetGeometry()->GetPadSizePhi();
583 Double_t amplitude = qhit *
584 (CPVCumulPadResponse(z+dz,x+dx) - CPVCumulPadResponse(z+dz,x-dx) -
585 CPVCumulPadResponse(z-dz,x+dx) + CPVCumulPadResponse(z-dz,x-dx));
586 return (Float_t)amplitude;
589 //____________________________________________________________________________
590 Double_t AliPHOSv1::CPVCumulPadResponse(Double_t x, Double_t y) {
591 // ------------------------------------------------------------------------
592 // Cumulative pad response function
593 // It includes several terms from the CF decomposition in electrostatics
594 // Note: this cumulative function is wrong since omits some terms
595 // but the cell amplitude obtained with it is correct because
596 // these omitting terms cancel
597 // Author: Yuri Kharlov (after Serguei Sadovski)
599 // ------------------------------------------------------------------------
601 const Double_t kA=1.0;
602 const Double_t kB=0.7;
604 Double_t r2 = x*x + y*y;
606 Double_t cumulPRF = 0;
607 for (Int_t i=0; i<=4; i++) {
608 Double_t b1 = (2*i + 1) * kB;
609 cumulPRF += TMath::Power(-1,i) * TMath::ATan( xy / (b1*TMath::Sqrt(b1*b1 + r2)) );
611 cumulPRF *= kA/(2*TMath::Pi());