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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 ---
30 #include <TParticle.h>
31 #include <TVirtualMC.h>
33 // --- Standard library ---
36 // --- AliRoot header files ---
37 #include "AliPHOSCPVDigit.h"
38 #include "AliPHOSGeometry.h"
39 #include "AliPHOSHit.h"
40 #include "AliPHOSQAFloatCheckable.h"
41 #include "AliPHOSQAIntCheckable.h"
42 #include "AliPHOSQAMeanChecker.h"
43 #include "AliPHOSv1.h"
49 //____________________________________________________________________________
50 AliPHOSv1::AliPHOSv1():
53 // default ctor: initialze data memebers
59 fLightYieldMean = 0. ;
60 fIntrinsicPINEfficiency = 0. ;
61 fLightYieldAttenuation = 0. ;
62 fRecalibrationFactor = 0. ;
63 fElectronsPerGeV = 0. ;
70 //____________________________________________________________________________
71 AliPHOSv1::AliPHOSv1(const char *name, const char *title):
76 // - fHits (the "normal" one), which retains the hits associated with
77 // the current primary particle being tracked
78 // (this array is reset after each primary has been tracked).
83 // We do not want to save in TreeH the raw hits
84 // But save the cumulated hits instead (need to create the branch myself)
85 // It is put in the Digit Tree because the TreeH is filled after each primary
86 // and the TreeD at the end of the event (branch is set in FinishEvent() ).
88 fHits= new TClonesArray("AliPHOSHit",1000) ;
89 gAlice->GetMCApp()->AddHitList(fHits) ;
93 fIshunt = 2 ; // All hits are associated with primary particles
95 //Photoelectron statistics:
96 // The light yield is a poissonian distribution of the number of
97 // photons created in the PbWo4 crystal, calculated using following formula
98 // NumberOfPhotons = EnergyLost * LightYieldMean* APDEfficiency *
99 // exp (-LightYieldAttenuation * DistanceToPINdiodeFromTheHit);
100 // LightYieldMean is parameter calculated to be over 47000 photons per GeV
101 // APDEfficiency is 0.02655
102 // k_0 is 0.0045 from Valery Antonenko
103 // The number of electrons created in the APD is
104 // NumberOfElectrons = APDGain * LightYield
105 // The APD Gain is 300
106 fLightYieldMean = 47000;
107 fIntrinsicPINEfficiency = 0.02655 ; //APD= 0.1875/0.1271 * 0.018 (PIN)
108 fLightYieldAttenuation = 0.0045 ;
109 fRecalibrationFactor = 13.418/ fLightYieldMean ;
110 fElectronsPerGeV = 2.77e+8 ;
112 fLightFactor = fLightYieldMean * fIntrinsicPINEfficiency ;
113 fAPDFactor = (fRecalibrationFactor/100.) * fAPDGain ;
116 Int_t nb = GetGeometry()->GetNModules() ;
119 fQAHitsMul = new AliPHOSQAIntCheckable("HitsM") ;
120 fQATotEner = new AliPHOSQAFloatCheckable("TotEn") ;
121 fQAHitsMulB = new TClonesArray("AliPHOSQAIntCheckable",nb) ;
122 fQAHitsMulB->SetOwner() ;
123 fQATotEnerB = new TClonesArray("AliPHOSQAFloatCheckable", nb);
124 fQATotEnerB->SetOwner() ;
127 for ( i = 0 ; i < nb ; i++ ) {
128 sprintf(tempo, "HitsMB%d", i+1) ;
129 new( (*fQAHitsMulB)[i]) AliPHOSQAIntCheckable(tempo) ;
130 sprintf(tempo, "TotEnB%d", i+1) ;
131 new( (*fQATotEnerB)[i] ) AliPHOSQAFloatCheckable(tempo) ;
134 AliPHOSQAMeanChecker * hmc = new AliPHOSQAMeanChecker("HitsMul", 100. ,25.) ;
135 AliPHOSQAMeanChecker * emc = new AliPHOSQAMeanChecker("TotEner", 10. ,5.) ;
136 AliPHOSQAMeanChecker * bhmc = new AliPHOSQAMeanChecker("HitsMulB", 100. ,5.) ;
137 AliPHOSQAMeanChecker * bemc = new AliPHOSQAMeanChecker("TotEnerB", 2. ,.5) ;
139 // associate checkables and checkers
140 fQAHitsMul->AddChecker(hmc) ;
141 fQATotEner->AddChecker(emc) ;
142 for ( i = 0 ; i < nb ; i++ ) {
143 (static_cast<AliPHOSQAIntCheckable*>((*fQAHitsMulB)[i]))->AddChecker(bhmc) ;
144 (static_cast<AliPHOSQAFloatCheckable*>((*fQATotEnerB)[i]))->AddChecker(bemc) ;
149 //____________________________________________________________________________
150 AliPHOSv1::~AliPHOSv1()
160 fQAHitsMulB->Delete() ;
165 fQATotEnerB->Delete() ;
171 //____________________________________________________________________________
172 void AliPHOSv1::AddHit(Int_t shunt, Int_t primary, Int_t tracknumber, Int_t Id, Float_t * hits)
174 // Add a hit to the hit list.
175 // A PHOS hit is the sum of all hits in a single crystal from one primary and within some time gate
180 Bool_t deja = kFALSE ;
181 AliPHOSGeometry * geom = GetGeometry() ;
183 newHit = new AliPHOSHit(shunt, primary, tracknumber, Id, hits) ;
185 for ( hitCounter = fNhits-1 ; hitCounter >= 0 && !deja ; hitCounter-- ) {
186 curHit = dynamic_cast<AliPHOSHit*>((*fHits)[hitCounter]) ;
187 if(curHit->GetPrimary() != primary) break ;
188 // We add hits with the same primary, while GEANT treats primaries succesively
189 if( *curHit == *newHit ) {
196 new((*fHits)[fNhits]) AliPHOSHit(*newHit) ;
197 // get the block Id number
199 geom->AbsToRelNumbering(Id, relid) ;
200 // and fill the relevant QA checkable (only if in PbW04)
201 if ( relid[1] == 0 ) {
202 fQAHitsMul->Update(1) ;
203 (static_cast<AliPHOSQAIntCheckable*>((*fQAHitsMulB)[relid[0]-1]))->Update(1) ;
211 //____________________________________________________________________________
212 void AliPHOSv1::FinishPrimary()
214 // called at the end of each track (primary) by AliRun
215 // hits are reset for each new track
216 // accumulate the total hit-multiplicity
218 // fQAHitsMul->Update( fHits->GetEntriesFast() ) ;
222 //____________________________________________________________________________
223 void AliPHOSv1::FinishEvent()
225 // called at the end of each event by AliRun
226 // accumulate the hit-multiplicity and total energy per block
227 // if the values have been updated check it
231 if ( fQATotEner->HasChanged() ) {
232 fQATotEner->CheckMe() ;
233 fQATotEner->Reset() ;
238 if ( fQAHitsMulB && fQATotEnerB ) {
239 for (i = 0 ; i < GetGeometry()->GetNModules() ; i++) {
240 AliPHOSQAIntCheckable * ci = static_cast<AliPHOSQAIntCheckable*>((*fQAHitsMulB)[i]) ;
241 AliPHOSQAFloatCheckable* cf = static_cast<AliPHOSQAFloatCheckable*>((*fQATotEnerB)[i]) ;
242 if ( ci->HasChanged() ) {
246 if ( cf->HasChanged() ) {
253 // check the total multiplicity
256 if ( fQAHitsMul->HasChanged() ) {
257 fQAHitsMul->CheckMe() ;
258 fQAHitsMul->Reset() ;
262 AliDetector::FinishEvent();
264 //____________________________________________________________________________
265 void AliPHOSv1::StepManager(void)
267 // Accumulates hits as long as the track stays in a single crystal or CPV gas Cell
269 Int_t relid[4] ; // (box, layer, row, column) indices
270 Int_t absid ; // absolute cell ID number
271 Float_t xyzte[5]={-1000.,-1000.,-1000.,0.,0.} ; // position wrt MRS, time and energy deposited
272 TLorentzVector pos ; // Lorentz vector of the track current position
275 Int_t tracknumber = gAlice->GetMCApp()->GetCurrentTrackNumber() ;
276 TString name = GetGeometry()->GetName() ;
280 if( gMC->CurrentVolID(copy) == gMC->VolId("PCPQ") &&
281 (gMC->IsTrackEntering() ) &&
282 gMC->TrackCharge() != 0) {
284 gMC -> TrackPosition(pos);
286 Float_t xyzm[3], xyzd[3] ;
288 for (i=0; i<3; i++) xyzm[i] = pos[i];
289 gMC -> Gmtod (xyzm, xyzd, 1); // transform coordinate from master to daughter system
291 Float_t xyd[3]={0,0,0} ; //local position of the entering
296 // Current momentum of the hit's track in the local ref. system
297 TLorentzVector pmom ; //momentum of the particle initiated hit
298 gMC -> TrackMomentum(pmom);
299 Float_t pm[3], pd[3];
303 gMC -> Gmtod (pm, pd, 2); // transform 3-momentum from master to daughter system
308 // Digitize the current CPV hit:
310 // 1. find pad response and
311 gMC->CurrentVolOffID(3,moduleNumber);
314 TClonesArray *cpvDigits = new TClonesArray("AliPHOSCPVDigit",0); // array of digits for current hit
315 CPVDigitize(pmom,xyd,cpvDigits);
320 Int_t idigit,ndigits;
322 // 2. go through the current digit list and sum digits in pads
324 ndigits = cpvDigits->GetEntriesFast();
325 for (idigit=0; idigit<ndigits-1; idigit++) {
326 AliPHOSCPVDigit *cpvDigit1 = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(idigit));
327 Float_t x1 = cpvDigit1->GetXpad() ;
328 Float_t z1 = cpvDigit1->GetYpad() ;
329 for (Int_t jdigit=idigit+1; jdigit<ndigits; jdigit++) {
330 AliPHOSCPVDigit *cpvDigit2 = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(jdigit));
331 Float_t x2 = cpvDigit2->GetXpad() ;
332 Float_t z2 = cpvDigit2->GetYpad() ;
333 if (x1==x2 && z1==z2) {
334 Float_t qsum = cpvDigit1->GetQpad() + cpvDigit2->GetQpad() ;
335 cpvDigit2->SetQpad(qsum) ;
336 cpvDigits->RemoveAt(idigit) ;
340 cpvDigits->Compress() ;
342 // 3. add digits to temporary hit list fTmpHits
344 ndigits = cpvDigits->GetEntriesFast();
345 for (idigit=0; idigit<ndigits; idigit++) {
346 AliPHOSCPVDigit *cpvDigit = dynamic_cast<AliPHOSCPVDigit*>(cpvDigits->UncheckedAt(idigit));
347 relid[0] = moduleNumber + 1 ; // CPV (or PHOS) module number
348 relid[1] =-1 ; // means CPV
349 relid[2] = cpvDigit->GetXpad() ; // column number of a pad
350 relid[3] = cpvDigit->GetYpad() ; // row number of a pad
352 // get the absolute Id number
353 GetGeometry()->RelToAbsNumbering(relid, absid) ;
355 // add current digit to the temporary hit list
357 xyzte[3] = gMC->TrackTime() ;
358 xyzte[4] = cpvDigit->GetQpad() ; // amplitude in a pad
359 AddHit(fIshunt, -1, tracknumber, absid, xyzte); // -1: No need in primary for CPV
361 if (cpvDigit->GetQpad() > 0.02) {
362 xmean += cpvDigit->GetQpad() * (cpvDigit->GetXpad() + 0.5);
363 zmean += cpvDigit->GetQpad() * (cpvDigit->GetYpad() + 0.5);
364 qsum += cpvDigit->GetQpad();
376 if(gMC->CurrentVolID(copy) == gMC->VolId("PXTL") ) { // We are inside a PBWO crystal
378 gMC->TrackPosition(pos) ;
383 Float_t global[3], local[3] ;
387 Float_t lostenergy = gMC->Edep();
389 //Put in the TreeK particle entering PHOS and all its parents
390 if ( gMC->IsTrackEntering() ){
392 gMC -> Gmtod (xyzte, xyzd, 1); // transform coordinate from master to daughter system
393 if (xyzd[1] < -GetGeometry()->GetCrystalSize(1)/2.+0.001){ //Entered close to forward surface
394 TParticle * part = 0 ;
395 Int_t parent = gAlice->GetMCApp()->GetCurrentTrackNumber() ;
396 while ( parent != -1 ) {
397 part = gAlice->GetMCApp()->Particle(parent) ;
398 part->SetBit(kKeepBit);
399 parent = part->GetFirstMother() ;
403 if ( lostenergy != 0 ) { // Track is inside the crystal and deposits some energy
404 xyzte[3] = gMC->TrackTime() ;
406 gMC->CurrentVolOffID(10, moduleNumber) ; // get the PHOS module number ;
409 gMC->CurrentVolOffID(3, strip);
411 gMC->CurrentVolOffID(2, cell);
413 Int_t row = 1 + GetGeometry()->GetNZ() - strip % GetGeometry()->GetNZ() ;
414 Int_t col = (Int_t) TMath::Ceil((Double_t) strip/GetGeometry()->GetNZ()) -1 ;
416 absid = (moduleNumber-1)*GetGeometry()->GetNCristalsInModule() +
417 row + (col*GetGeometry()->GetEMCAGeometry()->GetNCellsInStrip() + cell-1)*GetGeometry()->GetNZ() ;
419 gMC->Gmtod(global, local, 1) ;
421 //Calculates the light yield, the number of photons produced in the
423 Float_t lightYield = gRandom->Poisson(fLightFactor * lostenergy *
424 exp(-fLightYieldAttenuation *
425 (local[1]+GetGeometry()->GetCrystalSize(1)/2.0 ))
428 //Calculates de energy deposited in the crystal
429 xyzte[4] = fAPDFactor * lightYield ;
433 primary = gAlice->GetMCApp()->GetPrimary( gAlice->GetMCApp()->GetCurrentTrackNumber() );
434 else if(fIshunt == 2){
435 primary = gAlice->GetMCApp()->GetCurrentTrackNumber() ;
436 TParticle * part = gAlice->GetMCApp()->Particle(primary) ;
437 while ( !part->TestBit(kKeepBit) ) {
438 primary = part->GetFirstMother() ;
439 if(primary == -1) break ; //there is a possibility that particle passed e.g. thermal isulator and hits a side
440 //surface of the crystal. In this case it may have no primary at all.
441 //We can not easily separate this case from the case when this is part of the shower,
442 //developed in the neighboring crystal.
443 part = gAlice->GetMCApp()->Particle(primary) ;
448 // add current hit to the hit list
449 // Info("StepManager","%d %d", primary, tracknumber) ;
450 AddHit(fIshunt, primary,tracknumber, absid, xyzte);
452 // fill the relevant QA Checkables
453 fQATotEner->Update( xyzte[4] ) ; // total energy in PHOS
454 (static_cast<AliPHOSQAFloatCheckable*>((*fQATotEnerB)[moduleNumber-1]))->Update( xyzte[4] ) ; // energy in this block
456 } // there is deposited energy
457 } // we are inside a PHOS Xtal
461 //____________________________________________________________________________
462 void AliPHOSv1::CPVDigitize (TLorentzVector p, Float_t *zxhit, TClonesArray *cpvDigits)
464 // ------------------------------------------------------------------------
465 // Digitize one CPV hit:
466 // On input take exact 4-momentum p and position zxhit of the hit,
467 // find the pad response around this hit and
468 // put the amplitudes in the pads into array digits
470 // Author: Yuri Kharlov (after Serguei Sadovsky)
472 // ------------------------------------------------------------------------
474 const Float_t kCelWr = GetGeometry()->GetPadSizePhi()/2; // Distance between wires (2 wires above 1 pad)
475 const Float_t kDetR = 0.1; // Relative energy fluctuation in track for 100 e-
476 const Float_t kdEdx = 4.0; // Average energy loss in CPV;
477 const Int_t kNgamz = 5; // Ionization size in Z
478 const Int_t kNgamx = 9; // Ionization size in Phi
479 const Float_t kNoise = 0.03; // charge noise in one pad
483 // Just a reminder on axes notation in the CPV module:
484 // axis Z goes along the beam
485 // axis X goes across the beam in the module plane
486 // axis Y is a normal to the module plane showing from the IP
488 Float_t hitX = zxhit[0];
489 Float_t hitZ =-zxhit[1];
492 Float_t pNorm = p.Py();
493 Float_t eloss = kdEdx;
495 //Info("CPVDigitize", "YVK : %f %f | %f %f %d", hitX, hitZ, pX, pZ, pNorm) ;
497 Float_t dZY = pZ/pNorm * GetGeometry()->GetCPVGasThickness();
498 Float_t dXY = pX/pNorm * GetGeometry()->GetCPVGasThickness();
499 gRandom->Rannor(rnor1,rnor2);
500 eloss *= (1 + kDetR*rnor1) *
501 TMath::Sqrt((1 + ( pow(dZY,2) + pow(dXY,2) ) / pow(GetGeometry()->GetCPVGasThickness(),2)));
502 Float_t zhit1 = hitZ + GetGeometry()->GetCPVActiveSize(1)/2 - dZY/2;
503 Float_t xhit1 = hitX + GetGeometry()->GetCPVActiveSize(0)/2 - dXY/2;
504 Float_t zhit2 = zhit1 + dZY;
505 Float_t xhit2 = xhit1 + dXY;
507 Int_t iwht1 = (Int_t) (xhit1 / kCelWr); // wire (x) coordinate "in"
508 Int_t iwht2 = (Int_t) (xhit2 / kCelWr); // wire (x) coordinate "out"
512 if (iwht1==iwht2) { // incline 1-wire hit
514 zxe[0][0] = (zhit1 + zhit2 - dZY*0.57735) / 2;
515 zxe[1][0] = (iwht1 + 0.5) * kCelWr;
517 zxe[0][1] = (zhit1 + zhit2 + dZY*0.57735) / 2;
518 zxe[1][1] = (iwht1 + 0.5) * kCelWr;
521 else if (TMath::Abs(iwht1-iwht2) != 1) { // incline 3-wire hit
523 Int_t iwht3 = (iwht1 + iwht2) / 2;
524 Float_t xwht1 = (iwht1 + 0.5) * kCelWr; // wire 1
525 Float_t xwht2 = (iwht2 + 0.5) * kCelWr; // wire 2
526 Float_t xwht3 = (iwht3 + 0.5) * kCelWr; // wire 3
527 Float_t xwr13 = (xwht1 + xwht3) / 2; // center 13
528 Float_t xwr23 = (xwht2 + xwht3) / 2; // center 23
529 Float_t dxw1 = xhit1 - xwr13;
530 Float_t dxw2 = xhit2 - xwr23;
531 Float_t egm1 = TMath::Abs(dxw1) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
532 Float_t egm2 = TMath::Abs(dxw2) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
533 Float_t egm3 = kCelWr / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) + kCelWr );
534 zxe[0][0] = (dXY*(xwr13-xwht1)/dXY + zhit1 + zhit1) / 2;
536 zxe[2][0] = eloss * egm1;
537 zxe[0][1] = (dXY*(xwr23-xwht1)/dXY + zhit1 + zhit2) / 2;
539 zxe[2][1] = eloss * egm2;
540 zxe[0][2] = dXY*(xwht3-xwht1)/dXY + zhit1;
542 zxe[2][2] = eloss * egm3;
544 else { // incline 2-wire hit
546 Float_t xwht1 = (iwht1 + 0.5) * kCelWr;
547 Float_t xwht2 = (iwht2 + 0.5) * kCelWr;
548 Float_t xwr12 = (xwht1 + xwht2) / 2;
549 Float_t dxw1 = xhit1 - xwr12;
550 Float_t dxw2 = xhit2 - xwr12;
551 Float_t egm1 = TMath::Abs(dxw1) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) );
552 Float_t egm2 = TMath::Abs(dxw2) / ( TMath::Abs(dxw1) + TMath::Abs(dxw2) );
553 zxe[0][0] = (zhit1 + zhit2 - dZY*egm1) / 2;
555 zxe[2][0] = eloss * egm1;
556 zxe[0][1] = (zhit1 + zhit2 + dZY*egm2) / 2;
558 zxe[2][1] = eloss * egm2;
561 // Finite size of ionization region
563 Int_t nCellZ = GetGeometry()->GetNumberOfCPVPadsZ();
564 Int_t nCellX = GetGeometry()->GetNumberOfCPVPadsPhi();
565 Int_t nz3 = (kNgamz+1)/2;
566 Int_t nx3 = (kNgamx+1)/2;
567 cpvDigits->Expand(nIter*kNgamx*kNgamz);
568 TClonesArray &ldigits = *(static_cast<TClonesArray *>(cpvDigits));
570 for (Int_t iter=0; iter<nIter; iter++) {
572 Float_t zhit = zxe[0][iter];
573 Float_t xhit = zxe[1][iter];
574 Float_t qhit = zxe[2][iter];
575 Float_t zcell = zhit / GetGeometry()->GetPadSizeZ();
576 Float_t xcell = xhit / GetGeometry()->GetPadSizePhi();
577 if ( zcell<=0 || xcell<=0 ||
578 zcell>=nCellZ || xcell>=nCellX) return;
579 Int_t izcell = (Int_t) zcell;
580 Int_t ixcell = (Int_t) xcell;
581 Float_t zc = zcell - izcell - 0.5;
582 Float_t xc = xcell - ixcell - 0.5;
583 for (Int_t iz=1; iz<=kNgamz; iz++) {
584 Int_t kzg = izcell + iz - nz3;
585 if (kzg<=0 || kzg>nCellZ) continue;
586 Float_t zg = (Float_t)(iz-nz3) - zc;
587 for (Int_t ix=1; ix<=kNgamx; ix++) {
588 Int_t kxg = ixcell + ix - nx3;
589 if (kxg<=0 || kxg>nCellX) continue;
590 Float_t xg = (Float_t)(ix-nx3) - xc;
592 // Now calculate pad response
593 Float_t qpad = CPVPadResponseFunction(qhit,zg,xg);
594 qpad += kNoise*rnor2;
595 if (qpad<0) continue;
597 // Fill the array with pad response ID and amplitude
598 new(ldigits[cpvDigits->GetEntriesFast()]) AliPHOSCPVDigit(kxg,kzg,qpad);
604 //____________________________________________________________________________
605 Float_t AliPHOSv1::CPVPadResponseFunction(Float_t qhit, Float_t zhit, Float_t xhit) {
606 // ------------------------------------------------------------------------
607 // Calculate the amplitude in one CPV pad using the
608 // cumulative pad response function
609 // Author: Yuri Kharlov (after Serguei Sadovski)
611 // ------------------------------------------------------------------------
613 Double_t dz = GetGeometry()->GetPadSizeZ() / 2;
614 Double_t dx = GetGeometry()->GetPadSizePhi() / 2;
615 Double_t z = zhit * GetGeometry()->GetPadSizeZ();
616 Double_t x = xhit * GetGeometry()->GetPadSizePhi();
617 Double_t amplitude = qhit *
618 (CPVCumulPadResponse(z+dz,x+dx) - CPVCumulPadResponse(z+dz,x-dx) -
619 CPVCumulPadResponse(z-dz,x+dx) + CPVCumulPadResponse(z-dz,x-dx));
620 return (Float_t)amplitude;
623 //____________________________________________________________________________
624 Double_t AliPHOSv1::CPVCumulPadResponse(Double_t x, Double_t y) {
625 // ------------------------------------------------------------------------
626 // Cumulative pad response function
627 // It includes several terms from the CF decomposition in electrostatics
628 // Note: this cumulative function is wrong since omits some terms
629 // but the cell amplitude obtained with it is correct because
630 // these omitting terms cancel
631 // Author: Yuri Kharlov (after Serguei Sadovski)
633 // ------------------------------------------------------------------------
635 const Double_t kA=1.0;
636 const Double_t kB=0.7;
638 Double_t r2 = x*x + y*y;
640 Double_t cumulPRF = 0;
641 for (Int_t i=0; i<=4; i++) {
642 Double_t b1 = (2*i + 1) * kB;
643 cumulPRF += TMath::Power(-1,i) * TMath::ATan( xy / (b1*TMath::Sqrt(b1*b1 + r2)) );
645 cumulPRF *= kA/(2*TMath::Pi());