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 ---
45 #include <strstream.h>
47 // --- AliRoot header files ---
49 #include "AliPHOSv1.h"
50 #include "AliPHOSHit.h"
51 #include "AliPHOSCPVDigit.h"
55 #include "AliPHOSGeometry.h"
56 #include "AliPHOSQAIntCheckable.h"
57 #include "AliPHOSQAFloatCheckable.h"
58 #include "AliPHOSQAMeanChecker.h"
62 //____________________________________________________________________________
63 AliPHOSv1::AliPHOSv1():
66 // default ctor: initialze data memebers
72 fLightYieldMean = 0. ;
73 fIntrinsicPINEfficiency = 0. ;
74 fLightYieldAttenuation = 0. ;
75 fRecalibrationFactor = 0. ;
76 fElectronsPerGeV = 0. ;
83 //____________________________________________________________________________
84 AliPHOSv1::AliPHOSv1(const char *name, const char *title):
89 // - fHits (the "normal" one), which retains the hits associated with
90 // the current primary particle being tracked
91 // (this array is reset after each primary has been tracked).
96 // We do not want to save in TreeH the raw hits
97 // But save the cumulated hits instead (need to create the branch myself)
98 // It is put in the Digit Tree because the TreeH is filled after each primary
99 // and the TreeD at the end of the event (branch is set in FinishEvent() ).
101 fHits= new TClonesArray("AliPHOSHit",1000) ;
102 gAlice->AddHitList(fHits) ;
106 fIshunt = 2 ; // All hits are associated with primary particles
108 //Photoelectron statistics:
109 // The light yield is a poissonian distribution of the number of
110 // photons created in the PbWo4 crystal, calculated using following formula
111 // NumberOfPhotons = EnergyLost * LightYieldMean* APDEfficiency *
112 // exp (-LightYieldAttenuation * DistanceToPINdiodeFromTheHit);
113 // LightYieldMean is parameter calculated to be over 47000 photons per GeV
114 // APDEfficiency is 0.02655
115 // k_0 is 0.0045 from Valery Antonenko
116 // The number of electrons created in the APD is
117 // NumberOfElectrons = APDGain * LightYield
118 // The APD Gain is 300
119 fLightYieldMean = 47000;
120 fIntrinsicPINEfficiency = 0.02655 ; //APD= 0.1875/0.1271 * 0.018 (PIN)
121 fLightYieldAttenuation = 0.0045 ;
122 fRecalibrationFactor = 13.418/ fLightYieldMean ;
123 fElectronsPerGeV = 2.77e+8 ;
125 fLightFactor = fLightYieldMean * fIntrinsicPINEfficiency ;
126 fAPDFactor = (fRecalibrationFactor/100.) * fAPDGain ;
129 Int_t nb = GetGeometry()->GetNModules() ;
132 fQAHitsMul = new AliPHOSQAIntCheckable("HitsM") ;
133 fQATotEner = new AliPHOSQAFloatCheckable("TotEn") ;
134 fQAHitsMulB = new TClonesArray("AliPHOSQAIntCheckable",nb) ;
135 fQAHitsMulB->SetOwner() ;
136 fQATotEnerB = new TClonesArray("AliPHOSQAFloatCheckable", nb);
137 fQATotEnerB->SetOwner() ;
140 for ( i = 0 ; i < nb ; i++ ) {
141 sprintf(tempo, "HitsMB%d", i+1) ;
142 new( (*fQAHitsMulB)[i]) AliPHOSQAIntCheckable(tempo) ;
143 sprintf(tempo, "TotEnB%d", i+1) ;
144 new( (*fQATotEnerB)[i] ) AliPHOSQAFloatCheckable(tempo) ;
147 AliPHOSQAMeanChecker * hmc = new AliPHOSQAMeanChecker("HitsMul", 100. ,25.) ;
148 AliPHOSQAMeanChecker * emc = new AliPHOSQAMeanChecker("TotEner", 10. ,5.) ;
149 AliPHOSQAMeanChecker * bhmc = new AliPHOSQAMeanChecker("HitsMulB", 100. ,5.) ;
150 AliPHOSQAMeanChecker * bemc = new AliPHOSQAMeanChecker("TotEnerB", 2. ,.5) ;
152 // associate checkables and checkers
153 fQAHitsMul->AddChecker(hmc) ;
154 fQATotEner->AddChecker(emc) ;
155 for ( i = 0 ; i < nb ; i++ ) {
156 (static_cast<AliPHOSQAIntCheckable*>((*fQAHitsMulB)[i]))->AddChecker(bhmc) ;
157 (static_cast<AliPHOSQAFloatCheckable*>((*fQATotEnerB)[i]))->AddChecker(bemc) ;
162 //____________________________________________________________________________
163 AliPHOSv1::~AliPHOSv1()
174 fQAHitsMulB->Delete() ;
179 fQATotEnerB->Delete() ;
185 //____________________________________________________________________________
186 void AliPHOSv1::AddHit(Int_t shunt, Int_t primary, Int_t tracknumber, Int_t Id, Float_t * hits)
188 // Add a hit to the hit list.
189 // A PHOS hit is the sum of all hits in a single crystal from one primary and within some time gate
194 Bool_t deja = kFALSE ;
195 AliPHOSGeometry * geom = GetGeometry() ;
197 newHit = new AliPHOSHit(shunt, primary, tracknumber, Id, hits) ;
199 for ( hitCounter = fNhits-1 ; hitCounter >= 0 && !deja ; hitCounter-- ) {
200 curHit = dynamic_cast<AliPHOSHit*>((*fHits)[hitCounter]) ;
201 if(curHit->GetPrimary() != primary) break ;
202 // We add hits with the same primary, while GEANT treats primaries succesively
203 if( *curHit == *newHit ) {
210 new((*fHits)[fNhits]) AliPHOSHit(*newHit) ;
211 // get the block Id number
213 geom->AbsToRelNumbering(Id, relid) ;
214 // and fill the relevant QA checkable (only if in PbW04)
215 if ( relid[1] == 0 ) {
216 fQAHitsMul->Update(1) ;
217 (static_cast<AliPHOSQAIntCheckable*>((*fQAHitsMulB)[relid[0]-1]))->Update(1) ;
225 //____________________________________________________________________________
226 void AliPHOSv1::FinishPrimary()
228 // called at the end of each track (primary) by AliRun
229 // hits are reset for each new track
230 // accumulate the total hit-multiplicity
232 // fQAHitsMul->Update( fHits->GetEntriesFast() ) ;
236 //____________________________________________________________________________
237 void AliPHOSv1::FinishEvent()
239 // called at the end of each event by AliRun
240 // accumulate the hit-multiplicity and total energy per block
241 // if the values have been updated check it
244 if ( fQATotEner->HasChanged() ) {
245 fQATotEner->CheckMe() ;
246 fQATotEner->Reset() ;
251 if ( fQAHitsMulB && fQATotEnerB ) {
252 for (i = 0 ; i < GetGeometry()->GetNModules() ; i++) {
253 AliPHOSQAIntCheckable * ci = static_cast<AliPHOSQAIntCheckable*>((*fQAHitsMulB)[i]) ;
254 AliPHOSQAFloatCheckable* cf = static_cast<AliPHOSQAFloatCheckable*>((*fQATotEnerB)[i]) ;
255 if ( ci->HasChanged() ) {
259 if ( cf->HasChanged() ) {
266 // check the total multiplicity
269 if ( fQAHitsMul->HasChanged() ) {
270 fQAHitsMul->CheckMe() ;
271 fQAHitsMul->Reset() ;
275 //____________________________________________________________________________
276 void AliPHOSv1::StepManager(void)
278 // Accumulates hits as long as the track stays in a single crystal or CPV gas Cell
280 Int_t relid[4] ; // (box, layer, row, column) indices
281 Int_t absid ; // absolute cell ID number
282 Float_t xyzte[5]={-1000.,-1000.,-1000.,0.,0.} ; // position wrt MRS, time and energy deposited
283 TLorentzVector pos ; // Lorentz vector of the track current position
286 Int_t tracknumber = gAlice->CurrentTrack() ;
287 Int_t primary = gAlice->GetPrimary( gAlice->CurrentTrack() );
288 TString name = GetGeometry()->GetName() ;
292 if( gMC->CurrentVolID(copy) == gMC->VolId("PCPQ") &&
293 (gMC->IsTrackEntering() ) &&
294 gMC->TrackCharge() != 0) {
296 gMC -> TrackPosition(pos);
298 Float_t xyzm[3], xyzd[3] ;
300 for (i=0; i<3; i++) xyzm[i] = pos[i];
301 gMC -> Gmtod (xyzm, xyzd, 1); // transform coordinate from master to daughter system
303 Float_t xyd[3]={0,0,0} ; //local position of the entering
308 // Current momentum of the hit's track in the local ref. system
309 TLorentzVector pmom ; //momentum of the particle initiated hit
310 gMC -> TrackMomentum(pmom);
311 Float_t pm[3], pd[3];
315 gMC -> Gmtod (pm, pd, 2); // transform 3-momentum from master to daughter system
320 // Digitize the current CPV hit:
322 // 1. find pad response and
323 gMC->CurrentVolOffID(3,moduleNumber);
326 TClonesArray *cpvDigits = new TClonesArray("AliPHOSCPVDigit",0); // array of digits for current hit
327 CPVDigitize(pmom,xyd,moduleNumber,cpvDigits);
332 Int_t idigit,ndigits;
334 // 2. go through the current digit list and sum digits in pads
336 ndigits = cpvDigits->GetEntriesFast();
337 for (idigit=0; idigit<ndigits-1; idigit++) {
338 AliPHOSCPVDigit *cpvDigit1 = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(idigit));
339 Float_t x1 = cpvDigit1->GetXpad() ;
340 Float_t z1 = cpvDigit1->GetYpad() ;
341 for (Int_t jdigit=idigit+1; jdigit<ndigits; jdigit++) {
342 AliPHOSCPVDigit *cpvDigit2 = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(jdigit));
343 Float_t x2 = cpvDigit2->GetXpad() ;
344 Float_t z2 = cpvDigit2->GetYpad() ;
345 if (x1==x2 && z1==z2) {
346 Float_t qsum = cpvDigit1->GetQpad() + cpvDigit2->GetQpad() ;
347 cpvDigit2->SetQpad(qsum) ;
348 cpvDigits->RemoveAt(idigit) ;
352 cpvDigits->Compress() ;
354 // 3. add digits to temporary hit list fTmpHits
356 ndigits = cpvDigits->GetEntriesFast();
357 for (idigit=0; idigit<ndigits; idigit++) {
358 AliPHOSCPVDigit *cpvDigit = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(idigit));
359 relid[0] = moduleNumber + 1 ; // CPV (or PHOS) module number
360 relid[1] =-1 ; // means CPV
361 relid[2] = cpvDigit->GetXpad() ; // column number of a pad
362 relid[3] = cpvDigit->GetYpad() ; // row number of a pad
364 // get the absolute Id number
365 GetGeometry()->RelToAbsNumbering(relid, absid) ;
367 // add current digit to the temporary hit list
369 xyzte[3] = gMC->TrackTime() ;
370 xyzte[4] = cpvDigit->GetQpad() ; // amplitude in a pad
371 primary = -1; // No need in primary for CPV
372 AddHit(fIshunt, primary, tracknumber, absid, xyzte);
374 if (cpvDigit->GetQpad() > 0.02) {
375 xmean += cpvDigit->GetQpad() * (cpvDigit->GetXpad() + 0.5);
376 zmean += cpvDigit->GetQpad() * (cpvDigit->GetYpad() + 0.5);
377 qsum += cpvDigit->GetQpad();
389 if(gMC->CurrentVolID(copy) == gMC->VolId("PXTL") ) { // We are inside a PBWO crystal
391 gMC->TrackPosition(pos) ;
396 Float_t global[3], local[3] ;
400 Float_t lostenergy = gMC->Edep();
402 //Put in the TreeK particle entering PHOS and all its parents
403 if ( gMC->IsTrackEntering() ){
405 gMC -> Gmtod (xyzte, xyzd, 1); // transform coordinate from master to daughter system
406 if (xyzd[1] > GetGeometry()->GetCrystalSize(1)/2-0.002 ||
407 xyzd[1] < -GetGeometry()->GetCrystalSize(1)/2+0.002) {
408 TParticle * part = 0 ;
409 Int_t parent = gAlice->CurrentTrack() ;
410 while ( parent != -1 ) {
411 part = gAlice->Particle(parent) ;
412 part->SetBit(kKeepBit);
413 parent = part->GetFirstMother() ;
417 if ( lostenergy != 0 ) { // Track is inside the crystal and deposits some energy
418 xyzte[3] = gMC->TrackTime() ;
420 gMC->CurrentVolOffID(10, moduleNumber) ; // get the PHOS module number ;
423 gMC->CurrentVolOffID(3, strip);
425 gMC->CurrentVolOffID(2, cell);
427 Int_t row = 1 + GetGeometry()->GetNZ() - strip % GetGeometry()->GetNZ() ;
428 Int_t col = (Int_t) TMath::Ceil((Double_t) strip/GetGeometry()->GetNZ()) -1 ;
430 absid = (moduleNumber-1)*GetGeometry()->GetNCristalsInModule() +
431 row + (col*GetGeometry()->GetEMCAGeometry()->GetNCellsInStrip() + cell-1)*GetGeometry()->GetNZ() ;
433 gMC->Gmtod(global, local, 1) ;
435 //Calculates the light yield, the number of photons produced in the
437 Float_t lightYield = gRandom->Poisson(fLightFactor * lostenergy *
438 exp(-fLightYieldAttenuation *
439 (local[1]+GetGeometry()->GetCrystalSize(1)/2.0 ))
442 //Calculates de energy deposited in the crystal
443 xyzte[4] = fAPDFactor * lightYield ;
445 // add current hit to the hit list
446 //cout << "AliPHOSv1::StepManager " << primary << " " << tracknumber << endl ;
447 AddHit(fIshunt, primary,tracknumber, absid, xyzte);
449 // fill the relevant QA Checkables
450 fQATotEner->Update( xyzte[4] ) ; // total energy in PHOS
451 (static_cast<AliPHOSQAFloatCheckable*>((*fQATotEnerB)[moduleNumber-1]))->Update( xyzte[4] ) ; // energy in this block
453 } // there is deposited energy
454 } // we are inside a PHOS Xtal
458 //____________________________________________________________________________
459 void AliPHOSv1::CPVDigitize (TLorentzVector p, Float_t *zxhit, Int_t moduleNumber, TClonesArray *cpvDigits)
461 // ------------------------------------------------------------------------
462 // Digitize one CPV hit:
463 // On input take exact 4-momentum p and position zxhit of the hit,
464 // find the pad response around this hit and
465 // put the amplitudes in the pads into array digits
467 // Author: Yuri Kharlov (after Serguei Sadovsky)
469 // ------------------------------------------------------------------------
471 const Float_t kCelWr = GetGeometry()->GetPadSizePhi()/2; // Distance between wires (2 wires above 1 pad)
472 const Float_t kDetR = 0.1; // Relative energy fluctuation in track for 100 e-
473 const Float_t kdEdx = 4.0; // Average energy loss in CPV;
474 const Int_t kNgamz = 5; // Ionization size in Z
475 const Int_t kNgamx = 9; // Ionization size in Phi
476 const Float_t kNoise = 0.03; // charge noise in one pad
480 // Just a reminder on axes notation in the CPV module:
481 // axis Z goes along the beam
482 // axis X goes across the beam in the module plane
483 // axis Y is a normal to the module plane showing from the IP
485 Float_t hitX = zxhit[0];
486 Float_t hitZ =-zxhit[1];
489 Float_t pNorm = p.Py();
490 Float_t eloss = kdEdx;
492 // cout << "CPVDigitize: YVK : "<<hitX<<" "<<hitZ<<" | "<<pX<<" "<<pZ<<" "<<pNorm<<endl;
494 Float_t dZY = pZ/pNorm * GetGeometry()->GetCPVGasThickness();
495 Float_t dXY = pX/pNorm * GetGeometry()->GetCPVGasThickness();
496 gRandom->Rannor(rnor1,rnor2);
497 eloss *= (1 + kDetR*rnor1) *
498 TMath::Sqrt((1 + ( pow(dZY,2) + pow(dXY,2) ) / pow(GetGeometry()->GetCPVGasThickness(),2)));
499 Float_t zhit1 = hitZ + GetGeometry()->GetCPVActiveSize(1)/2 - dZY/2;
500 Float_t xhit1 = hitX + GetGeometry()->GetCPVActiveSize(0)/2 - dXY/2;
501 Float_t zhit2 = zhit1 + dZY;
502 Float_t xhit2 = xhit1 + dXY;
504 Int_t iwht1 = (Int_t) (xhit1 / kCelWr); // wire (x) coordinate "in"
505 Int_t iwht2 = (Int_t) (xhit2 / kCelWr); // wire (x) coordinate "out"
509 if (iwht1==iwht2) { // incline 1-wire hit
511 zxe[0][0] = (zhit1 + zhit2 - dZY*0.57735) / 2;
512 zxe[1][0] = (iwht1 + 0.5) * kCelWr;
514 zxe[0][1] = (zhit1 + zhit2 + dZY*0.57735) / 2;
515 zxe[1][1] = (iwht1 + 0.5) * kCelWr;
518 else if (TMath::Abs(iwht1-iwht2) != 1) { // incline 3-wire hit
520 Int_t iwht3 = (iwht1 + iwht2) / 2;
521 Float_t xwht1 = (iwht1 + 0.5) * kCelWr; // wire 1
522 Float_t xwht2 = (iwht2 + 0.5) * kCelWr; // wire 2
523 Float_t xwht3 = (iwht3 + 0.5) * kCelWr; // wire 3
524 Float_t xwr13 = (xwht1 + xwht3) / 2; // center 13
525 Float_t xwr23 = (xwht2 + xwht3) / 2; // center 23
526 Float_t dxw1 = xhit1 - xwr13;
527 Float_t dxw2 = xhit2 - xwr23;
528 Float_t egm1 = TMath::Abs(dxw1) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
529 Float_t egm2 = TMath::Abs(dxw2) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
530 Float_t egm3 = kCelWr / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
531 zxe[0][0] = (dXY*(xwr13-xwht1)/dXY + zhit1 + zhit1) / 2;
533 zxe[2][0] = eloss * egm1;
534 zxe[0][1] = (dXY*(xwr23-xwht1)/dXY + zhit1 + zhit2) / 2;
536 zxe[2][1] = eloss * egm2;
537 zxe[0][2] = dXY*(xwht3-xwht1)/dXY + zhit1;
539 zxe[2][2] = eloss * egm3;
541 else { // incline 2-wire hit
543 Float_t xwht1 = (iwht1 + 0.5) * kCelWr;
544 Float_t xwht2 = (iwht2 + 0.5) * kCelWr;
545 Float_t xwr12 = (xwht1 + xwht2) / 2;
546 Float_t dxw1 = xhit1 - xwr12;
547 Float_t dxw2 = xhit2 - xwr12;
548 Float_t egm1 = TMath::Abs(dxw1) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) );
549 Float_t egm2 = TMath::Abs(dxw2) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) );
550 zxe[0][0] = (zhit1 + zhit2 - dZY*egm1) / 2;
552 zxe[2][0] = eloss * egm1;
553 zxe[0][1] = (zhit1 + zhit2 + dZY*egm2) / 2;
555 zxe[2][1] = eloss * egm2;
558 // Finite size of ionization region
560 Int_t nCellZ = GetGeometry()->GetNumberOfCPVPadsZ();
561 Int_t nCellX = GetGeometry()->GetNumberOfCPVPadsPhi();
562 Int_t nz3 = (kNgamz+1)/2;
563 Int_t nx3 = (kNgamx+1)/2;
564 cpvDigits->Expand(nIter*kNgamx*kNgamz);
565 TClonesArray &ldigits = *(static_cast<TClonesArray *>(cpvDigits));
567 for (Int_t iter=0; iter<nIter; iter++) {
569 Float_t zhit = zxe[0][iter];
570 Float_t xhit = zxe[1][iter];
571 Float_t qhit = zxe[2][iter];
572 Float_t zcell = zhit / GetGeometry()->GetPadSizeZ();
573 Float_t xcell = xhit / GetGeometry()->GetPadSizePhi();
574 if ( zcell<=0 || xcell<=0 ||
575 zcell>=nCellZ || xcell>=nCellX) return;
576 Int_t izcell = (Int_t) zcell;
577 Int_t ixcell = (Int_t) xcell;
578 Float_t zc = zcell - izcell - 0.5;
579 Float_t xc = xcell - ixcell - 0.5;
580 for (Int_t iz=1; iz<=kNgamz; iz++) {
581 Int_t kzg = izcell + iz - nz3;
582 if (kzg<=0 || kzg>nCellZ) continue;
583 Float_t zg = (Float_t)(iz-nz3) - zc;
584 for (Int_t ix=1; ix<=kNgamx; ix++) {
585 Int_t kxg = ixcell + ix - nx3;
586 if (kxg<=0 || kxg>nCellX) continue;
587 Float_t xg = (Float_t)(ix-nx3) - xc;
589 // Now calculate pad response
590 Float_t qpad = CPVPadResponseFunction(qhit,zg,xg);
591 qpad += kNoise*rnor2;
592 if (qpad<0) continue;
594 // Fill the array with pad response ID and amplitude
595 new(ldigits[cpvDigits->GetEntriesFast()]) AliPHOSCPVDigit(kxg,kzg,qpad);
601 //____________________________________________________________________________
602 Float_t AliPHOSv1::CPVPadResponseFunction(Float_t qhit, Float_t zhit, Float_t xhit) {
603 // ------------------------------------------------------------------------
604 // Calculate the amplitude in one CPV pad using the
605 // cumulative pad response function
606 // Author: Yuri Kharlov (after Serguei Sadovski)
608 // ------------------------------------------------------------------------
610 Double_t dz = GetGeometry()->GetPadSizeZ() / 2;
611 Double_t dx = GetGeometry()->GetPadSizePhi() / 2;
612 Double_t z = zhit * GetGeometry()->GetPadSizeZ();
613 Double_t x = xhit * GetGeometry()->GetPadSizePhi();
614 Double_t amplitude = qhit *
615 (CPVCumulPadResponse(z+dz,x+dx) - CPVCumulPadResponse(z+dz,x-dx) -
616 CPVCumulPadResponse(z-dz,x+dx) + CPVCumulPadResponse(z-dz,x-dx));
617 return (Float_t)amplitude;
620 //____________________________________________________________________________
621 Double_t AliPHOSv1::CPVCumulPadResponse(Double_t x, Double_t y) {
622 // ------------------------------------------------------------------------
623 // Cumulative pad response function
624 // It includes several terms from the CF decomposition in electrostatics
625 // Note: this cumulative function is wrong since omits some terms
626 // but the cell amplitude obtained with it is correct because
627 // these omitting terms cancel
628 // Author: Yuri Kharlov (after Serguei Sadovski)
630 // ------------------------------------------------------------------------
632 const Double_t kA=1.0;
633 const Double_t kB=0.7;
635 Double_t r2 = x*x + y*y;
637 Double_t cumulPRF = 0;
638 for (Int_t i=0; i<=4; i++) {
639 Double_t b1 = (2*i + 1) * kB;
640 cumulPRF += TMath::Power(-1,i) * TMath::ATan( xy / (b1*TMath::Sqrt(b1*b1 + r2)) );
642 cumulPRF *= kA/(2*TMath::Pi());