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18 //_________________________________________________________________________
19 // Implementation version v1 of PHOS Manager class
22 // Layout EMC + CPV has name IHEP:
23 // Produces hits for CPV, cumulated hits
26 //*-- Author: Yves Schutz (SUBATECH)
29 // --- ROOT system ---
33 #include <TParticle.h>
36 #include <TVirtualMC.h>
38 // --- Standard library ---
43 // --- AliRoot header files ---
46 #include "AliPHOSCPVDigit.h"
47 #include "AliPHOSGeometry.h"
48 #include "AliPHOSHit.h"
49 #include "AliPHOSQAFloatCheckable.h"
50 #include "AliPHOSQAIntCheckable.h"
51 #include "AliPHOSQAMeanChecker.h"
52 #include "AliPHOSv1.h"
58 //____________________________________________________________________________
59 AliPHOSv1::AliPHOSv1():
62 // default ctor: initialze data memebers
68 fLightYieldMean = 0. ;
69 fIntrinsicPINEfficiency = 0. ;
70 fLightYieldAttenuation = 0. ;
71 fRecalibrationFactor = 0. ;
72 fElectronsPerGeV = 0. ;
79 //____________________________________________________________________________
80 AliPHOSv1::AliPHOSv1(const char *name, const char *title):
85 // - fHits (the "normal" one), which retains the hits associated with
86 // the current primary particle being tracked
87 // (this array is reset after each primary has been tracked).
92 // We do not want to save in TreeH the raw hits
93 // But save the cumulated hits instead (need to create the branch myself)
94 // It is put in the Digit Tree because the TreeH is filled after each primary
95 // and the TreeD at the end of the event (branch is set in FinishEvent() ).
97 fHits= new TClonesArray("AliPHOSHit",1000) ;
98 gAlice->GetMCApp()->AddHitList(fHits) ;
102 fIshunt = 2 ; // All hits are associated with primary particles
104 //Photoelectron statistics:
105 // The light yield is a poissonian distribution of the number of
106 // photons created in the PbWo4 crystal, calculated using following formula
107 // NumberOfPhotons = EnergyLost * LightYieldMean* APDEfficiency *
108 // exp (-LightYieldAttenuation * DistanceToPINdiodeFromTheHit);
109 // LightYieldMean is parameter calculated to be over 47000 photons per GeV
110 // APDEfficiency is 0.02655
111 // k_0 is 0.0045 from Valery Antonenko
112 // The number of electrons created in the APD is
113 // NumberOfElectrons = APDGain * LightYield
114 // The APD Gain is 300
115 fLightYieldMean = 47000;
116 fIntrinsicPINEfficiency = 0.02655 ; //APD= 0.1875/0.1271 * 0.018 (PIN)
117 fLightYieldAttenuation = 0.0045 ;
118 fRecalibrationFactor = 13.418/ fLightYieldMean ;
119 fElectronsPerGeV = 2.77e+8 ;
121 fLightFactor = fLightYieldMean * fIntrinsicPINEfficiency ;
122 fAPDFactor = (fRecalibrationFactor/100.) * fAPDGain ;
125 Int_t nb = GetGeometry()->GetNModules() ;
128 fQAHitsMul = new AliPHOSQAIntCheckable("HitsM") ;
129 fQATotEner = new AliPHOSQAFloatCheckable("TotEn") ;
130 fQAHitsMulB = new TClonesArray("AliPHOSQAIntCheckable",nb) ;
131 fQAHitsMulB->SetOwner() ;
132 fQATotEnerB = new TClonesArray("AliPHOSQAFloatCheckable", nb);
133 fQATotEnerB->SetOwner() ;
136 for ( i = 0 ; i < nb ; i++ ) {
137 sprintf(tempo, "HitsMB%d", i+1) ;
138 new( (*fQAHitsMulB)[i]) AliPHOSQAIntCheckable(tempo) ;
139 sprintf(tempo, "TotEnB%d", i+1) ;
140 new( (*fQATotEnerB)[i] ) AliPHOSQAFloatCheckable(tempo) ;
143 AliPHOSQAMeanChecker * hmc = new AliPHOSQAMeanChecker("HitsMul", 100. ,25.) ;
144 AliPHOSQAMeanChecker * emc = new AliPHOSQAMeanChecker("TotEner", 10. ,5.) ;
145 AliPHOSQAMeanChecker * bhmc = new AliPHOSQAMeanChecker("HitsMulB", 100. ,5.) ;
146 AliPHOSQAMeanChecker * bemc = new AliPHOSQAMeanChecker("TotEnerB", 2. ,.5) ;
148 // associate checkables and checkers
149 fQAHitsMul->AddChecker(hmc) ;
150 fQATotEner->AddChecker(emc) ;
151 for ( i = 0 ; i < nb ; i++ ) {
152 (static_cast<AliPHOSQAIntCheckable*>((*fQAHitsMulB)[i]))->AddChecker(bhmc) ;
153 (static_cast<AliPHOSQAFloatCheckable*>((*fQATotEnerB)[i]))->AddChecker(bemc) ;
158 //____________________________________________________________________________
159 AliPHOSv1::~AliPHOSv1()
169 fQAHitsMulB->Delete() ;
174 fQATotEnerB->Delete() ;
180 //____________________________________________________________________________
181 void AliPHOSv1::AddHit(Int_t shunt, Int_t primary, Int_t tracknumber, Int_t Id, Float_t * hits)
183 // Add a hit to the hit list.
184 // A PHOS hit is the sum of all hits in a single crystal from one primary and within some time gate
189 Bool_t deja = kFALSE ;
190 AliPHOSGeometry * geom = GetGeometry() ;
192 newHit = new AliPHOSHit(shunt, primary, tracknumber, Id, hits) ;
194 for ( hitCounter = fNhits-1 ; hitCounter >= 0 && !deja ; hitCounter-- ) {
195 curHit = dynamic_cast<AliPHOSHit*>((*fHits)[hitCounter]) ;
196 if(curHit->GetPrimary() != primary) break ;
197 // We add hits with the same primary, while GEANT treats primaries succesively
198 if( *curHit == *newHit ) {
205 new((*fHits)[fNhits]) AliPHOSHit(*newHit) ;
206 // get the block Id number
208 geom->AbsToRelNumbering(Id, relid) ;
209 // and fill the relevant QA checkable (only if in PbW04)
210 if ( relid[1] == 0 ) {
211 fQAHitsMul->Update(1) ;
212 (static_cast<AliPHOSQAIntCheckable*>((*fQAHitsMulB)[relid[0]-1]))->Update(1) ;
220 //____________________________________________________________________________
221 void AliPHOSv1::FinishPrimary()
223 // called at the end of each track (primary) by AliRun
224 // hits are reset for each new track
225 // accumulate the total hit-multiplicity
227 // fQAHitsMul->Update( fHits->GetEntriesFast() ) ;
231 //____________________________________________________________________________
232 void AliPHOSv1::FinishEvent()
234 // called at the end of each event by AliRun
235 // accumulate the hit-multiplicity and total energy per block
236 // if the values have been updated check it
240 if ( fQATotEner->HasChanged() ) {
241 fQATotEner->CheckMe() ;
242 fQATotEner->Reset() ;
247 if ( fQAHitsMulB && fQATotEnerB ) {
248 for (i = 0 ; i < GetGeometry()->GetNModules() ; i++) {
249 AliPHOSQAIntCheckable * ci = static_cast<AliPHOSQAIntCheckable*>((*fQAHitsMulB)[i]) ;
250 AliPHOSQAFloatCheckable* cf = static_cast<AliPHOSQAFloatCheckable*>((*fQATotEnerB)[i]) ;
251 if ( ci->HasChanged() ) {
255 if ( cf->HasChanged() ) {
262 // check the total multiplicity
265 if ( fQAHitsMul->HasChanged() ) {
266 fQAHitsMul->CheckMe() ;
267 fQAHitsMul->Reset() ;
271 AliDetector::FinishEvent();
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->GetMCApp()->GetCurrentTrackNumber() ;
285 TString name = GetGeometry()->GetName() ;
289 if( gMC->CurrentVolID(copy) == gMC->VolId("PCPQ") &&
290 (gMC->IsTrackEntering() ) &&
291 gMC->TrackCharge() != 0) {
293 gMC -> TrackPosition(pos);
295 Float_t xyzm[3], xyzd[3] ;
297 for (i=0; i<3; i++) xyzm[i] = pos[i];
298 gMC -> Gmtod (xyzm, xyzd, 1); // transform coordinate from master to daughter system
300 Float_t xyd[3]={0,0,0} ; //local position of the entering
305 // Current momentum of the hit's track in the local ref. system
306 TLorentzVector pmom ; //momentum of the particle initiated hit
307 gMC -> TrackMomentum(pmom);
308 Float_t pm[3], pd[3];
312 gMC -> Gmtod (pm, pd, 2); // transform 3-momentum from master to daughter system
317 // Digitize the current CPV hit:
319 // 1. find pad response and
320 gMC->CurrentVolOffID(3,moduleNumber);
323 TClonesArray *cpvDigits = new TClonesArray("AliPHOSCPVDigit",0); // array of digits for current hit
324 CPVDigitize(pmom,xyd,cpvDigits);
329 Int_t idigit,ndigits;
331 // 2. go through the current digit list and sum digits in pads
333 ndigits = cpvDigits->GetEntriesFast();
334 for (idigit=0; idigit<ndigits-1; idigit++) {
335 AliPHOSCPVDigit *cpvDigit1 = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(idigit));
336 Float_t x1 = cpvDigit1->GetXpad() ;
337 Float_t z1 = cpvDigit1->GetYpad() ;
338 for (Int_t jdigit=idigit+1; jdigit<ndigits; jdigit++) {
339 AliPHOSCPVDigit *cpvDigit2 = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(jdigit));
340 Float_t x2 = cpvDigit2->GetXpad() ;
341 Float_t z2 = cpvDigit2->GetYpad() ;
342 if (x1==x2 && z1==z2) {
343 Float_t qsum = cpvDigit1->GetQpad() + cpvDigit2->GetQpad() ;
344 cpvDigit2->SetQpad(qsum) ;
345 cpvDigits->RemoveAt(idigit) ;
349 cpvDigits->Compress() ;
351 // 3. add digits to temporary hit list fTmpHits
353 ndigits = cpvDigits->GetEntriesFast();
354 for (idigit=0; idigit<ndigits; idigit++) {
355 AliPHOSCPVDigit *cpvDigit = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(idigit));
356 relid[0] = moduleNumber + 1 ; // CPV (or PHOS) module number
357 relid[1] =-1 ; // means CPV
358 relid[2] = cpvDigit->GetXpad() ; // column number of a pad
359 relid[3] = cpvDigit->GetYpad() ; // row number of a pad
361 // get the absolute Id number
362 GetGeometry()->RelToAbsNumbering(relid, absid) ;
364 // add current digit to the temporary hit list
366 xyzte[3] = gMC->TrackTime() ;
367 xyzte[4] = cpvDigit->GetQpad() ; // amplitude in a pad
368 AddHit(fIshunt, -1, tracknumber, absid, xyzte); // -1: No need in primary for CPV
370 if (cpvDigit->GetQpad() > 0.02) {
371 xmean += cpvDigit->GetQpad() * (cpvDigit->GetXpad() + 0.5);
372 zmean += cpvDigit->GetQpad() * (cpvDigit->GetYpad() + 0.5);
373 qsum += cpvDigit->GetQpad();
385 if(gMC->CurrentVolID(copy) == gMC->VolId("PXTL") ) { // We are inside a PBWO crystal
387 gMC->TrackPosition(pos) ;
392 Float_t global[3], local[3] ;
396 Float_t lostenergy = gMC->Edep();
398 //Put in the TreeK particle entering PHOS and all its parents
399 if ( gMC->IsTrackEntering() ){
401 gMC -> Gmtod (xyzte, xyzd, 1); // transform coordinate from master to daughter system
402 if (xyzd[1] < -GetGeometry()->GetCrystalSize(1)/2.+0.001){ //Entered close to forward surface
403 TParticle * part = 0 ;
404 Int_t parent = gAlice->GetMCApp()->GetCurrentTrackNumber() ;
405 while ( parent != -1 ) {
406 part = gAlice->GetMCApp()->Particle(parent) ;
407 part->SetBit(kKeepBit);
408 parent = part->GetFirstMother() ;
412 if ( lostenergy != 0 ) { // Track is inside the crystal and deposits some energy
413 xyzte[3] = gMC->TrackTime() ;
415 gMC->CurrentVolOffID(10, moduleNumber) ; // get the PHOS module number ;
418 gMC->CurrentVolOffID(3, strip);
420 gMC->CurrentVolOffID(2, cell);
422 Int_t row = 1 + GetGeometry()->GetNZ() - strip % GetGeometry()->GetNZ() ;
423 Int_t col = (Int_t) TMath::Ceil((Double_t) strip/GetGeometry()->GetNZ()) -1 ;
425 absid = (moduleNumber-1)*GetGeometry()->GetNCristalsInModule() +
426 row + (col*GetGeometry()->GetEMCAGeometry()->GetNCellsInStrip() + cell-1)*GetGeometry()->GetNZ() ;
428 gMC->Gmtod(global, local, 1) ;
430 //Calculates the light yield, the number of photons produced in the
432 Float_t lightYield = gRandom->Poisson(fLightFactor * lostenergy *
433 exp(-fLightYieldAttenuation *
434 (local[1]+GetGeometry()->GetCrystalSize(1)/2.0 ))
437 //Calculates de energy deposited in the crystal
438 xyzte[4] = fAPDFactor * lightYield ;
442 primary = gAlice->GetMCApp()->GetPrimary( gAlice->GetMCApp()->GetCurrentTrackNumber() );
443 else if(fIshunt == 2){
444 primary = gAlice->GetMCApp()->GetCurrentTrackNumber() ;
445 TParticle * part = gAlice->GetMCApp()->Particle(primary) ;
446 while ( !part->TestBit(kKeepBit) ) {
447 primary = part->GetFirstMother() ;
448 if(primary == -1) break ; //there is a possibility that particle passed e.g. thermal isulator and hits a side
449 //surface of the crystal. In this case it may have no primary at all.
450 //We can not easily separate this case from the case when this is part of the shower,
451 //developed in the neighboring crystal.
452 part = gAlice->GetMCApp()->Particle(primary) ;
457 // add current hit to the hit list
458 // Info("StepManager","%d %d", primary, tracknumber) ;
459 AddHit(fIshunt, primary,tracknumber, absid, xyzte);
461 // fill the relevant QA Checkables
462 fQATotEner->Update( xyzte[4] ) ; // total energy in PHOS
463 (static_cast<AliPHOSQAFloatCheckable*>((*fQATotEnerB)[moduleNumber-1]))->Update( xyzte[4] ) ; // energy in this block
465 } // there is deposited energy
466 } // we are inside a PHOS Xtal
470 //____________________________________________________________________________
471 void AliPHOSv1::CPVDigitize (TLorentzVector p, Float_t *zxhit, TClonesArray *cpvDigits)
473 // ------------------------------------------------------------------------
474 // Digitize one CPV hit:
475 // On input take exact 4-momentum p and position zxhit of the hit,
476 // find the pad response around this hit and
477 // put the amplitudes in the pads into array digits
479 // Author: Yuri Kharlov (after Serguei Sadovsky)
481 // ------------------------------------------------------------------------
483 const Float_t kCelWr = GetGeometry()->GetPadSizePhi()/2; // Distance between wires (2 wires above 1 pad)
484 const Float_t kDetR = 0.1; // Relative energy fluctuation in track for 100 e-
485 const Float_t kdEdx = 4.0; // Average energy loss in CPV;
486 const Int_t kNgamz = 5; // Ionization size in Z
487 const Int_t kNgamx = 9; // Ionization size in Phi
488 const Float_t kNoise = 0.03; // charge noise in one pad
492 // Just a reminder on axes notation in the CPV module:
493 // axis Z goes along the beam
494 // axis X goes across the beam in the module plane
495 // axis Y is a normal to the module plane showing from the IP
497 Float_t hitX = zxhit[0];
498 Float_t hitZ =-zxhit[1];
501 Float_t pNorm = p.Py();
502 Float_t eloss = kdEdx;
504 //Info("CPVDigitize", "YVK : %f %f | %f %f %d", hitX, hitZ, pX, pZ, pNorm) ;
506 Float_t dZY = pZ/pNorm * GetGeometry()->GetCPVGasThickness();
507 Float_t dXY = pX/pNorm * GetGeometry()->GetCPVGasThickness();
508 gRandom->Rannor(rnor1,rnor2);
509 eloss *= (1 + kDetR*rnor1) *
510 TMath::Sqrt((1 + ( pow(dZY,2) + pow(dXY,2) ) / pow(GetGeometry()->GetCPVGasThickness(),2)));
511 Float_t zhit1 = hitZ + GetGeometry()->GetCPVActiveSize(1)/2 - dZY/2;
512 Float_t xhit1 = hitX + GetGeometry()->GetCPVActiveSize(0)/2 - dXY/2;
513 Float_t zhit2 = zhit1 + dZY;
514 Float_t xhit2 = xhit1 + dXY;
516 Int_t iwht1 = (Int_t) (xhit1 / kCelWr); // wire (x) coordinate "in"
517 Int_t iwht2 = (Int_t) (xhit2 / kCelWr); // wire (x) coordinate "out"
521 if (iwht1==iwht2) { // incline 1-wire hit
523 zxe[0][0] = (zhit1 + zhit2 - dZY*0.57735) / 2;
524 zxe[1][0] = (iwht1 + 0.5) * kCelWr;
526 zxe[0][1] = (zhit1 + zhit2 + dZY*0.57735) / 2;
527 zxe[1][1] = (iwht1 + 0.5) * kCelWr;
530 else if (TMath::Abs(iwht1-iwht2) != 1) { // incline 3-wire hit
532 Int_t iwht3 = (iwht1 + iwht2) / 2;
533 Float_t xwht1 = (iwht1 + 0.5) * kCelWr; // wire 1
534 Float_t xwht2 = (iwht2 + 0.5) * kCelWr; // wire 2
535 Float_t xwht3 = (iwht3 + 0.5) * kCelWr; // wire 3
536 Float_t xwr13 = (xwht1 + xwht3) / 2; // center 13
537 Float_t xwr23 = (xwht2 + xwht3) / 2; // center 23
538 Float_t dxw1 = xhit1 - xwr13;
539 Float_t dxw2 = xhit2 - xwr23;
540 Float_t egm1 = TMath::Abs(dxw1) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
541 Float_t egm2 = TMath::Abs(dxw2) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
542 Float_t egm3 = kCelWr / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
543 zxe[0][0] = (dXY*(xwr13-xwht1)/dXY + zhit1 + zhit1) / 2;
545 zxe[2][0] = eloss * egm1;
546 zxe[0][1] = (dXY*(xwr23-xwht1)/dXY + zhit1 + zhit2) / 2;
548 zxe[2][1] = eloss * egm2;
549 zxe[0][2] = dXY*(xwht3-xwht1)/dXY + zhit1;
551 zxe[2][2] = eloss * egm3;
553 else { // incline 2-wire hit
555 Float_t xwht1 = (iwht1 + 0.5) * kCelWr;
556 Float_t xwht2 = (iwht2 + 0.5) * kCelWr;
557 Float_t xwr12 = (xwht1 + xwht2) / 2;
558 Float_t dxw1 = xhit1 - xwr12;
559 Float_t dxw2 = xhit2 - xwr12;
560 Float_t egm1 = TMath::Abs(dxw1) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) );
561 Float_t egm2 = TMath::Abs(dxw2) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) );
562 zxe[0][0] = (zhit1 + zhit2 - dZY*egm1) / 2;
564 zxe[2][0] = eloss * egm1;
565 zxe[0][1] = (zhit1 + zhit2 + dZY*egm2) / 2;
567 zxe[2][1] = eloss * egm2;
570 // Finite size of ionization region
572 Int_t nCellZ = GetGeometry()->GetNumberOfCPVPadsZ();
573 Int_t nCellX = GetGeometry()->GetNumberOfCPVPadsPhi();
574 Int_t nz3 = (kNgamz+1)/2;
575 Int_t nx3 = (kNgamx+1)/2;
576 cpvDigits->Expand(nIter*kNgamx*kNgamz);
577 TClonesArray &ldigits = *(static_cast<TClonesArray *>(cpvDigits));
579 for (Int_t iter=0; iter<nIter; iter++) {
581 Float_t zhit = zxe[0][iter];
582 Float_t xhit = zxe[1][iter];
583 Float_t qhit = zxe[2][iter];
584 Float_t zcell = zhit / GetGeometry()->GetPadSizeZ();
585 Float_t xcell = xhit / GetGeometry()->GetPadSizePhi();
586 if ( zcell<=0 || xcell<=0 ||
587 zcell>=nCellZ || xcell>=nCellX) return;
588 Int_t izcell = (Int_t) zcell;
589 Int_t ixcell = (Int_t) xcell;
590 Float_t zc = zcell - izcell - 0.5;
591 Float_t xc = xcell - ixcell - 0.5;
592 for (Int_t iz=1; iz<=kNgamz; iz++) {
593 Int_t kzg = izcell + iz - nz3;
594 if (kzg<=0 || kzg>nCellZ) continue;
595 Float_t zg = (Float_t)(iz-nz3) - zc;
596 for (Int_t ix=1; ix<=kNgamx; ix++) {
597 Int_t kxg = ixcell + ix - nx3;
598 if (kxg<=0 || kxg>nCellX) continue;
599 Float_t xg = (Float_t)(ix-nx3) - xc;
601 // Now calculate pad response
602 Float_t qpad = CPVPadResponseFunction(qhit,zg,xg);
603 qpad += kNoise*rnor2;
604 if (qpad<0) continue;
606 // Fill the array with pad response ID and amplitude
607 new(ldigits[cpvDigits->GetEntriesFast()]) AliPHOSCPVDigit(kxg,kzg,qpad);
613 //____________________________________________________________________________
614 Float_t AliPHOSv1::CPVPadResponseFunction(Float_t qhit, Float_t zhit, Float_t xhit) {
615 // ------------------------------------------------------------------------
616 // Calculate the amplitude in one CPV pad using the
617 // cumulative pad response function
618 // Author: Yuri Kharlov (after Serguei Sadovski)
620 // ------------------------------------------------------------------------
622 Double_t dz = GetGeometry()->GetPadSizeZ() / 2;
623 Double_t dx = GetGeometry()->GetPadSizePhi() / 2;
624 Double_t z = zhit * GetGeometry()->GetPadSizeZ();
625 Double_t x = xhit * GetGeometry()->GetPadSizePhi();
626 Double_t amplitude = qhit *
627 (CPVCumulPadResponse(z+dz,x+dx) - CPVCumulPadResponse(z+dz,x-dx) -
628 CPVCumulPadResponse(z-dz,x+dx) + CPVCumulPadResponse(z-dz,x-dx));
629 return (Float_t)amplitude;
632 //____________________________________________________________________________
633 Double_t AliPHOSv1::CPVCumulPadResponse(Double_t x, Double_t y) {
634 // ------------------------------------------------------------------------
635 // Cumulative pad response function
636 // It includes several terms from the CF decomposition in electrostatics
637 // Note: this cumulative function is wrong since omits some terms
638 // but the cell amplitude obtained with it is correct because
639 // these omitting terms cancel
640 // Author: Yuri Kharlov (after Serguei Sadovski)
642 // ------------------------------------------------------------------------
644 const Double_t kA=1.0;
645 const Double_t kB=0.7;
647 Double_t r2 = x*x + y*y;
649 Double_t cumulPRF = 0;
650 for (Int_t i=0; i<=4; i++) {
651 Double_t b1 = (2*i + 1) * kB;
652 cumulPRF += TMath::Power(-1,i) * TMath::ATan( xy / (b1*TMath::Sqrt(b1*b1 + r2)) );
654 cumulPRF *= kA/(2*TMath::Pi());