1 /**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
16 //////////////////////////////////////////////////////////////////////////
20 // HMPID class to perfom pattern recognition based on Hough transfrom //
21 // for single chamber //
22 //////////////////////////////////////////////////////////////////////////
24 #include "AliHMPIDRecon.h" //class header
25 #include "AliHMPIDCluster.h" //CkovAngle()
26 #include <TRotation.h> //TracePhot()
27 #include <TH1D.h> //HoughResponse()
28 #include <TClonesArray.h> //CkovAngle()
29 #include <AliESDtrack.h> //CkovAngle()
30 #include <AliESDfriendTrack.h> //CkovAngle()
32 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
33 AliHMPIDRecon::AliHMPIDRecon():
34 TTask("RichRec","RichPat"),
47 fTrkDir(0,0,1), // Just for test
48 fTrkPos(30,40), // Just for test
51 fParam(AliHMPIDParam::Instance())
54 //init of data members
57 fParam->SetRefIdx(fParam->MeanIdxRad()); // initialization of ref index to a default one
59 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
60 void AliHMPIDRecon::InitVars(Int_t n)
66 fPhotFlag = new Int_t[n];
67 fPhotClusIndex = new Int_t[n];
68 fPhotCkov = new Double_t[n];
69 fPhotPhi = new Double_t[n];
70 fPhotWei = new Double_t[n];
73 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
74 void AliHMPIDRecon::DeleteVars()const
80 delete [] fPhotClusIndex;
85 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
86 void AliHMPIDRecon::CkovAngle(AliESDtrack *pTrk,TClonesArray *pCluLst,Int_t index,Double_t nmean,Float_t xRa,Float_t yRa)
88 // Pattern recognition method based on Hough transform
89 // Arguments: pTrk - track for which Ckov angle is to be found
90 // pCluLst - list of clusters for this chamber
91 // Returns: - track ckov angle, [rad],
93 const Int_t nMinPhotAcc = 3; // Minimum number of photons required to perform the pattern recognition
95 Int_t nClusTot = pCluLst->GetEntries();
96 if(nClusTot>fParam->MultCut()) fIsWEIGHT = kTRUE; // offset to take into account bkg in reconstruction
97 else fIsWEIGHT = kFALSE;
101 Float_t xPc,yPc,th,ph;
102 pTrk->GetHMPIDtrk(xPc,yPc,th,ph); //initialize this track: th and ph angles at middle of RAD
103 SetTrack(xRa,yRa,th,ph);
105 fParam->SetRefIdx(nmean);
107 Float_t mipX=-1,mipY=-1;
108 Int_t chId=-1,mipQ=-1,sizeClu = -1;
112 for (Int_t iClu=0; iClu<pCluLst->GetEntriesFast();iClu++){//clusters loop
113 AliHMPIDCluster *pClu=(AliHMPIDCluster*)pCluLst->UncheckedAt(iClu); //get pointer to current cluster
114 if(iClu == index) { // this is the MIP! not a photon candidate: just store mip info
117 mipQ=(Int_t)pClu->Q();
118 sizeClu=pClu->Size();
122 Double_t thetaCer,phiCer;
123 if(FindPhotCkov(pClu->X(),pClu->Y(),thetaCer,phiCer)){ //find ckov angle for this photon candidate
124 fPhotCkov[fPhotCnt]=thetaCer; //actual theta Cerenkov (in TRS)
125 fPhotPhi [fPhotCnt]=phiCer;
126 fPhotClusIndex[fPhotCnt]=iClu; //actual phi Cerenkov (in TRS): -pi to come back to "unusual" ref system (X,Y,-Z)
127 fPhotCnt++; //increment counter of photon candidates
131 pTrk->SetHMPIDmip(mipX,mipY,mipQ,fPhotCnt); //store mip info in any case
132 pTrk->SetHMPIDcluIdx(chId,index+1000*sizeClu); //set index of cluster
134 if(fPhotCnt<=nMinPhotAcc) { //no reconstruction with <=3 photon candidates
135 pTrk->SetHMPIDsignal(kNoPhotAccept); //set the appropriate flag
139 fMipPos.Set(mipX,mipY);
141 //PATTERN RECOGNITION STARTED:
143 Int_t iNrec=FlagPhot(HoughResponse(),pCluLst,pTrk); //flag photons according to individual theta ckov with respect to most probable
145 pTrk->SetHMPIDmip(mipX,mipY,mipQ,iNrec); //store mip info
148 pTrk->SetHMPIDsignal(kNoPhotAccept); //no photon candidates are accepted
152 Double_t thetaC = FindRingCkov(pCluLst->GetEntries()); //find the best reconstructed theta Cherenkov
153 // FindRingGeom(thetaC,2);
154 pTrk->SetHMPIDsignal(thetaC); //store theta Cherenkov
155 pTrk->SetHMPIDchi2(fCkovSigma2); //store errors squared
159 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
160 Bool_t AliHMPIDRecon::FindPhotCkov(Double_t cluX,Double_t cluY,Double_t &thetaCer,Double_t &phiCer)
162 // Finds Cerenkov angle for this photon candidate
163 // Arguments: cluX,cluY - position of cadidate's cluster
164 // Returns: Cerenkov angle
168 Double_t zRad= -0.5*fParam->RadThick()-0.5*fParam->WinThick(); //z position of middle of RAD
169 TVector3 rad(fTrkPos.X(),fTrkPos.Y(),zRad); //impact point at middle of RAD
170 TVector3 pc(cluX,cluY,0.5*fParam->WinThick()+fParam->GapIdx()); //mip at PC
171 Double_t cluR = TMath::Sqrt((cluX-fTrkPos.X())*(cluX-fTrkPos.X())+
172 (cluY-fTrkPos.Y())*(cluY-fTrkPos.Y()));//ref. distance impact RAD-CLUSTER
173 Double_t phi=(pc-rad).Phi(); //phi of photon
176 Double_t ckov2=0.75+fTrkDir.Theta(); //start to find theta cerenkov in DRS
177 const Double_t kTol=0.01;
180 if(iIterCnt>=50) return kFALSE;
181 Double_t ckov=0.5*(ckov1+ckov2);
182 dirCkov.SetMagThetaPhi(1,ckov,phi);
183 TVector2 posC=TraceForward(dirCkov); //trace photon with actual angles
184 Double_t dist=cluR-(posC-fTrkPos).Mod(); //get distance between trial point and cluster position
185 if(posC.X()==-999) dist = - 999; //total reflection problem
186 iIterCnt++; //counter step
187 if (dist> kTol) ckov1=ckov; //cluster @ larger ckov
188 else if(dist<-kTol) ckov2=ckov; //cluster @ smaller ckov
189 else{ //precision achived: ckov in DRS found
190 dirCkov.SetMagThetaPhi(1,ckov,phi); //
191 Lors2Trs(dirCkov,thetaCer,phiCer); //find ckov (in TRS:the effective Cherenkov angle!)
196 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
197 TVector2 AliHMPIDRecon::TraceForward(TVector3 dirCkov)const
199 //Trace forward a photon from (x,y) up to PC
200 // Arguments: dirCkov photon vector in LORS
201 // Returns: pos of traced photon at PC
203 TVector2 pos(-999,-999);
204 Double_t thetaCer = dirCkov.Theta();
205 if(thetaCer > TMath::ASin(1./fParam->GetRefIdx())) return pos; //total refraction on WIN-GAP boundary
206 Double_t zRad= -0.5*fParam->RadThick()-0.5*fParam->WinThick(); //z position of middle of RAD
207 TVector3 posCkov(fTrkPos.X(),fTrkPos.Y(),zRad); //RAD: photon position is track position @ middle of RAD
208 Propagate(dirCkov,posCkov, -0.5*fParam->WinThick()); //go to RAD-WIN boundary
209 Refract (dirCkov, fParam->GetRefIdx(),fParam->WinIdx()); //RAD-WIN refraction
210 Propagate(dirCkov,posCkov, 0.5*fParam->WinThick()); //go to WIN-GAP boundary
211 Refract (dirCkov, fParam->WinIdx(),fParam->GapIdx()); //WIN-GAP refraction
212 Propagate(dirCkov,posCkov,0.5*fParam->WinThick()+fParam->GapThick()); //go to PC
213 pos.Set(posCkov.X(),posCkov.Y());
216 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
217 void AliHMPIDRecon::Lors2Trs(TVector3 dirCkov,Double_t &thetaCer,Double_t &phiCer)const
219 //Theta Cerenkov reconstruction
220 // Arguments: dirCkov photon vector in LORS
221 // Returns: thetaCer of photon in TRS
222 // phiCer of photon in TRS
224 // dirTrk.SetMagThetaPhi(1,fTrkDir.Theta(),fTrkDir.Phi());
225 // Double_t thetaCer = TMath::ACos(dirCkov*dirTrk);
226 TRotation mtheta; mtheta.RotateY(-fTrkDir.Theta());
227 TRotation mphi; mphi.RotateZ(-fTrkDir.Phi());
228 TRotation mrot=mtheta*mphi;
230 dirCkovTRS=mrot*dirCkov;
231 phiCer = dirCkovTRS.Phi(); //actual value of the phi of the photon
232 thetaCer= dirCkovTRS.Theta(); //actual value of thetaCerenkov of the photon
234 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
235 void AliHMPIDRecon::Trs2Lors(TVector3 dirCkov,Double_t &thetaCer,Double_t &phiCer)const
237 //Theta Cerenkov reconstruction
238 // Arguments: dirCkov photon vector in TRS
239 // Returns: thetaCer of photon in LORS
240 // phiCer of photon in LORS
241 TRotation mtheta; mtheta.RotateY(fTrkDir.Theta());
242 TRotation mphi; mphi.RotateZ(fTrkDir.Phi());
243 TRotation mrot=mphi*mtheta;
244 TVector3 dirCkovLORS;
245 dirCkovLORS=mrot*dirCkov;
246 phiCer = dirCkovLORS.Phi(); //actual value of the phi of the photon
247 thetaCer= dirCkovLORS.Theta(); //actual value of thetaCerenkov of the photon
249 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
250 void AliHMPIDRecon::FindRingGeom(Double_t ckovAng,Int_t level)
252 // Find area covered in the PC acceptance
253 // Arguments: ckovAng - cerenkov angle
254 // level - precision in finding area and portion of ring accepted (multiple of 50)
255 // Returns: area of the ring in cm^2 for given theta ckov
264 for(Int_t i=0;i<kN;i++){
266 pos1=TracePhot(ckovAng,Double_t(TMath::TwoPi()*(i+1)/kN)); //find a good trace for the first photon
267 if(pos1.X()==-999) continue; //no area: open ring
268 if(!fParam->IsInside(pos1.X(),pos1.Y(),0)) {
269 pos1 = IntWithEdge(fMipPos,pos1); // find the very first intersection...
271 if(!AliHMPIDParam::IsInDead(pos1.X(),pos1.Y())) nPoints++; //photon is accepted if not in dead zone
276 TVector2 pos2=TracePhot(ckovAng,Double_t(TMath::TwoPi()*(i+1)/kN)); //trace the next photon
277 if(pos2.X()==-999) continue; //no area: open ring
278 if(!fParam->IsInside(pos2.X(),pos2.Y(),0)) {
279 pos2 = IntWithEdge(fMipPos,pos2);
281 if(!AliHMPIDParam::IsInDead(pos2.X(),pos2.Y())) nPoints++; //photon is accepted if not in dead zone
283 area+=TMath::Abs((pos1-fMipPos).X()*(pos2-fMipPos).Y()-(pos1-fMipPos).Y()*(pos2-fMipPos).X()); //add area of the triangle...
286 //--- find area and length of the ring;
287 fRingAcc = (Double_t)nPoints/(Double_t)kN;
291 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
292 TVector2 AliHMPIDRecon::IntWithEdge(TVector2 p1,TVector2 p2)const
294 // It finds the intersection of the line for 2 points traced as photons
295 // and the edge of a given PC
296 // Arguments: 2 points obtained tracing the photons
297 // Returns: intersection point with detector (PC) edges
299 Double_t xmin = (p1.X()<p2.X())? p1.X():p2.X();
300 Double_t xmax = (p1.X()<p2.X())? p2.X():p1.X();
301 Double_t ymin = (p1.Y()<p2.Y())? p1.Y():p2.Y();
302 Double_t ymax = (p1.Y()<p2.Y())? p2.Y():p1.Y();
304 Double_t m = TMath::Tan((p2-p1).Phi());
306 //intersection with low X
307 pint.Set((Double_t)(p1.X() + (0-p1.Y())/m),0.);
308 if(pint.X()>=0 && pint.X()<=fParam->SizeAllX() &&
309 pint.X()>=xmin && pint.X()<=xmax &&
310 pint.Y()>=ymin && pint.Y()<=ymax) return pint;
311 //intersection with high X
312 pint.Set((Double_t)(p1.X() + (fParam->SizeAllY()-p1.Y())/m),(Double_t)(fParam->SizeAllY()));
313 if(pint.X()>=0 && pint.X()<=fParam->SizeAllX() &&
314 pint.X()>=xmin && pint.X()<=xmax &&
315 pint.Y()>=ymin && pint.Y()<=ymax) return pint;
316 //intersection with left Y
317 pint.Set(0.,(Double_t)(p1.Y() + m*(0-p1.X())));
318 if(pint.Y()>=0 && pint.Y()<=fParam->SizeAllY() &&
319 pint.Y()>=ymin && pint.Y()<=ymax &&
320 pint.X()>=xmin && pint.X()<=xmax) return pint;
321 //intersection with righ Y
322 pint.Set((Double_t)(fParam->SizeAllX()),(Double_t)(p1.Y() + m*(fParam->SizeAllX()-p1.X())));
323 if(pint.Y()>=0 && pint.Y()<=fParam->SizeAllY() &&
324 pint.Y()>=ymin && pint.Y()<=ymax &&
325 pint.X()>=xmin && pint.X()<=xmax) return pint;
328 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
329 Double_t AliHMPIDRecon::FindRingCkov(Int_t)
331 // Loops on all Ckov candidates and estimates the best Theta Ckov for a ring formed by those candidates. Also estimates an error for that Theat Ckov
332 // collecting errors for all single Ckov candidates thetas. (Assuming they are independent)
333 // Arguments: iNclus- total number of clusters in chamber for background estimation
334 // Return: best estimation of track Theta ckov
337 Double_t weightThetaCerenkov = 0.;
339 Double_t ckovMin=9999.,ckovMax=0.;
340 Double_t sigma2 = 0; //to collect error squared for this ring
342 for(Int_t i=0;i<fPhotCnt;i++){//candidates loop
343 if(fPhotFlag[i] == 2){
344 if(fPhotCkov[i]<ckovMin) ckovMin=fPhotCkov[i]; //find max and min Theta ckov from all candidates within probable window
345 if(fPhotCkov[i]>ckovMax) ckovMax=fPhotCkov[i];
346 weightThetaCerenkov += fPhotCkov[i]*fPhotWei[i];
347 wei += fPhotWei[i]; //collect weight as sum of all candidate weghts
349 sigma2 += 1./fParam->Sigma2(fTrkDir.Theta(),fTrkDir.Phi(),fPhotCkov[i],fPhotPhi[i]);
353 if(sigma2>0) fCkovSigma2=1./sigma2;
354 else fCkovSigma2=1e10;
356 if(wei != 0.) weightThetaCerenkov /= wei; else weightThetaCerenkov = 0.;
357 return weightThetaCerenkov;
359 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
360 Int_t AliHMPIDRecon::FlagPhot(Double_t ckov,TClonesArray *pCluLst, AliESDtrack *pTrk)
362 // Flag photon candidates if their individual ckov angle is inside the window around ckov angle returned by HoughResponse()
363 // Arguments: ckov- value of most probable ckov angle for track as returned by HoughResponse()
364 // Returns: number of photon candidates happened to be inside the window
366 // Photon Flag: Flag = 0 initial set;
367 // Flag = 1 good candidate (charge compatible with photon);
368 // Flag = 2 photon used for the ring;
369 Int_t *PhotIndex = new Int_t[fPhotCnt];
371 Int_t steps = (Int_t)((ckov )/ fDTheta); //how many times we need to have fDTheta to fill the distance between 0 and thetaCkovHough
373 Double_t tmin = (Double_t)(steps - 1)*fDTheta;
374 Double_t tmax = (Double_t)(steps)*fDTheta;
375 Double_t tavg = 0.5*(tmin+tmax);
377 tmin = tavg - 0.5*fWindowWidth; tmax = tavg + 0.5*fWindowWidth;
379 Int_t iInsideCnt = 0; //count photons which Theta ckov inside the window
380 for(Int_t i=0;i<fPhotCnt;i++){//photon candidates loop
382 if(fPhotCkov[i] >= tmin && fPhotCkov[i] <= tmax) {
384 PhotIndex[iInsideCnt]=fPhotClusIndex[i];
389 for (Int_t iClu=0; iClu<pCluLst->GetEntriesFast();iClu++){//clusters loop
390 AliHMPIDCluster *pClu=(AliHMPIDCluster*)pCluLst->UncheckedAt(iClu); //get pointer to current cluster
391 for(Int_t j=0; j<iInsideCnt; j++){
392 if(iClu==PhotIndex[j]) {
393 AliHMPIDCluster *pClus = new AliHMPIDCluster(*pClu);
394 pTrk->AddCalibObject(pClus);
404 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
405 TVector2 AliHMPIDRecon::TracePhot(Double_t ckovThe,Double_t ckovPhi)const
407 // Trace a single Ckov photon from emission point somewhere in radiator up to photocathode taking into account ref indexes of materials it travereses
408 // Arguments: ckovThe,ckovPhi- photon ckov angles in TRS, [rad]
409 // Returns: distance between photon point on PC and track projection
412 TVector3 dirTRS,dirLORS;
413 dirTRS.SetMagThetaPhi(1,ckovThe,ckovPhi); //photon in TRS
414 Trs2Lors(dirTRS,theta,phi);
415 dirLORS.SetMagThetaPhi(1,theta,phi); //photon in LORS
416 return TraceForward(dirLORS); //now foward tracing
418 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
419 void AliHMPIDRecon::Propagate(const TVector3 dir,TVector3 &pos,Double_t z)const
421 // Finds an intersection point between a line and XY plane shifted along Z.
422 // Arguments: dir,pos - vector along the line and any point of the line
423 // z - z coordinate of plain
425 // On exit: pos is the position if this intesection if any
426 static TVector3 nrm(0,0,1);
429 TVector3 diff=pnt-pos;
430 Double_t sint=(nrm*diff)/(nrm*dir);
433 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
434 void AliHMPIDRecon::Refract(TVector3 &dir,Double_t n1,Double_t n2)const
436 // Refract direction vector according to Snell law
438 // n1 - ref idx of first substance
439 // n2 - ref idx of second substance
441 // On exit: dir is new direction
442 Double_t sinref=(n1/n2)*TMath::Sin(dir.Theta());
443 if(TMath::Abs(sinref)>1.) dir.SetXYZ(-999,-999,-999);
444 else dir.SetTheta(TMath::ASin(sinref));
446 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
447 Double_t AliHMPIDRecon::HoughResponse()
453 Double_t kThetaMax=0.75;
454 Int_t nChannels = (Int_t)(kThetaMax/fDTheta+0.5);
455 TH1D *phots = new TH1D("Rphot" ,"phots" ,nChannels,0,kThetaMax);
456 TH1D *photsw = new TH1D("RphotWeighted" ,"photsw" ,nChannels,0,kThetaMax);
457 TH1D *resultw = new TH1D("resultw","resultw" ,nChannels,0,kThetaMax);
458 Int_t nBin = (Int_t)(kThetaMax/fDTheta);
459 Int_t nCorrBand = (Int_t)(fWindowWidth/(2*fDTheta));
461 for (Int_t i=0; i< fPhotCnt; i++){//photon cadidates loop
462 Double_t angle = fPhotCkov[i]; if(angle<0||angle>kThetaMax) continue;
464 Int_t bin = (Int_t)(0.5+angle/(fDTheta));
467 Double_t lowerlimit = ((Double_t)bin)*fDTheta - 0.5*fDTheta; Double_t upperlimit = ((Double_t)bin)*fDTheta + 0.5*fDTheta;
468 FindRingGeom(lowerlimit);
469 Double_t areaLow = GetRingArea();
470 FindRingGeom(upperlimit);
471 Double_t areaHigh = GetRingArea();
472 Double_t diffArea = areaHigh - areaLow;
473 if(diffArea>0) weight = 1./diffArea;
475 photsw->Fill(angle,weight);
477 }//photon candidates loop
479 for (Int_t i=1; i<=nBin;i++){
480 Int_t bin1= i-nCorrBand;
481 Int_t bin2= i+nCorrBand;
483 if(bin2>nBin)bin2=nBin;
484 Double_t sumPhots=phots->Integral(bin1,bin2);
485 if(sumPhots<3) continue; // if less then 3 photons don't trust to this ring
486 Double_t sumPhotsw=photsw->Integral(bin1,bin2);
487 resultw->Fill((Double_t)((i+0.5)*fDTheta),sumPhotsw);
489 // evaluate the "BEST" theta ckov as the maximum value of histogramm
490 Double_t *pVec = resultw->GetArray();
491 Int_t locMax = TMath::LocMax(nBin,pVec);
492 delete phots;delete photsw;delete resultw; // Reset and delete objects
494 return (Double_t)(locMax*fDTheta+0.5*fDTheta); //final most probable track theta ckov
496 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
497 Double_t AliHMPIDRecon::FindRingExt(Double_t ckov,Int_t ch,Double_t xPc,Double_t yPc,Double_t thRa,Double_t phRa)
499 // To find the acceptance of the ring even from external inputs.
502 Double_t xRa = xPc - (fParam->RadThick()+fParam->WinThick()+fParam->GapThick())*TMath::Cos(phRa)*TMath::Tan(thRa); //just linear extrapolation back to RAD
503 Double_t yRa = yPc - (fParam->RadThick()+fParam->WinThick()+fParam->GapThick())*TMath::Sin(phRa)*TMath::Tan(thRa);
508 Int_t ipc,ipadx,ipady;
511 SetTrack(xRa,yRa,thRa,phRa);
512 for(Int_t j=0;j<nStep;j++){
513 TVector2 pos; pos=TracePhot(ckov,j*TMath::TwoPi()/(Double_t)(nStep-1));
514 if(fParam->IsInDead(pos.X(),pos.Y())) continue;
515 fParam->Lors2Pad(pos.X(),pos.Y(),ipc,ipadx,ipady);
516 ipadx+=(ipc%2)*fParam->kPadPcX;
517 ipady+=(ipc/2)*fParam->kPadPcY;
518 if(fParam->IsDeadPad(ipadx,ipady,ch)) continue;
521 return ((Double_t)nPhi/(Double_t)nStep);