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1 : /**************************************************************************
2 : * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
3 : * *
4 : * Author: The ALICE Off-line Project. *
5 : * Contributors are mentioned in the code where appropriate. *
6 : * *
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 : **************************************************************************/
15 :
16 : //////////////////////////////////////////////////////////////////////////
17 : // //
18 : // AliHMPIDRecon //
19 : // //
20 : // HMPID class to perfom pattern recognition based on Hough transfrom //
21 : // for single chamber //
22 : //////////////////////////////////////////////////////////////////////////
23 :
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()
31 :
32 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
33 : AliHMPIDRecon::AliHMPIDRecon():
34 44 : TNamed("RichRec","RichPat"),
35 44 : fPhotCnt(-1),
36 44 : fPhotFlag(0x0),
37 44 : fPhotClusIndex(0x0),
38 44 : fPhotCkov(0x0),
39 44 : fPhotPhi(0x0),
40 44 : fPhotWei(0x0),
41 44 : fCkovSigma2(0),
42 44 : fIsWEIGHT(kFALSE),
43 44 : fDTheta(0.001),
44 44 : fWindowWidth(0.045),
45 44 : fRingArea(0),
46 44 : fRingAcc(0),
47 44 : fTrkDir(0,0,1), // Just for test
48 44 : fTrkPos(30,40), // Just for test
49 44 : fMipPos(0,0),
50 44 : fPc(0,0),
51 88 : fParam(AliHMPIDParam::Instance())
52 220 : {
53 : //..
54 : //init of data members
55 : //..
56 :
57 88 : fParam->SetRefIdx(fParam->MeanIdxRad()); // initialization of ref index to a default one
58 88 : }
59 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
60 : void AliHMPIDRecon::InitVars(Int_t n)
61 : {
62 : //..
63 : //Init some variables
64 : //..
65 16 : if(n<=0) return;
66 8 : fPhotFlag = new Int_t[n];
67 8 : fPhotClusIndex = new Int_t[n];
68 8 : fPhotCkov = new Double_t[n];
69 8 : fPhotPhi = new Double_t[n];
70 8 : fPhotWei = new Double_t[n];
71 : //
72 16 : }
73 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
74 : void AliHMPIDRecon::DeleteVars()const
75 : {
76 : //..
77 : //Delete variables
78 : //..
79 24 : delete [] fPhotFlag;
80 16 : delete [] fPhotClusIndex;
81 16 : delete [] fPhotCkov;
82 16 : delete [] fPhotPhi;
83 16 : delete [] fPhotWei;
84 8 : }
85 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
86 : void AliHMPIDRecon::CkovAngle(AliESDtrack *pTrk,TClonesArray *pCluLst,Int_t index,Double_t nmean,Float_t xRa,Float_t yRa)
87 : {
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],
92 :
93 : const Int_t nMinPhotAcc = 3; // Minimum number of photons required to perform the pattern recognition
94 :
95 16 : Int_t nClusTot = pCluLst->GetEntries();
96 :
97 8 : InitVars(nClusTot);
98 :
99 8 : Float_t xPc,yPc,th,ph;
100 8 : pTrk->GetHMPIDtrk(xPc,yPc,th,ph); //initialize this track: th and ph angles at middle of RAD
101 8 : SetTrack(xRa,yRa,th,ph);
102 :
103 8 : fParam->SetRefIdx(nmean);
104 :
105 : Float_t mipX=-1,mipY=-1;
106 : Int_t chId=-1,mipQ=-1,sizeClu = -1;
107 :
108 8 : fPhotCnt=0;
109 :
110 : Int_t nPads = 0;
111 :
112 336 : for (Int_t iClu=0; iClu<pCluLst->GetEntriesFast();iClu++){//clusters loop
113 160 : AliHMPIDCluster *pClu=(AliHMPIDCluster*)pCluLst->UncheckedAt(iClu); //get pointer to current cluster
114 160 : nPads+=pClu->Size();
115 160 : if(iClu == index) { // this is the MIP! not a photon candidate: just store mip info
116 8 : mipX = pClu->X();
117 8 : mipY = pClu->Y();
118 8 : mipQ=(Int_t)pClu->Q();
119 8 : sizeClu=pClu->Size();
120 8 : continue;
121 : }
122 152 : chId=pClu->Ch();
123 161 : if(pClu->Q()>2*fParam->QCut()) continue;
124 143 : Double_t thetaCer,phiCer;
125 143 : if(FindPhotCkov(pClu->X(),pClu->Y(),thetaCer,phiCer)){ //find ckov angle for this photon candidate
126 138 : fPhotCkov[fPhotCnt]=thetaCer; //actual theta Cerenkov (in TRS)
127 138 : fPhotPhi [fPhotCnt]=phiCer;
128 138 : fPhotClusIndex[fPhotCnt]=iClu; //actual phi Cerenkov (in TRS): -pi to come back to "unusual" ref system (X,Y,-Z)
129 138 : fPhotCnt++; //increment counter of photon candidates
130 138 : }
131 143 : }//clusters loop
132 :
133 8 : pTrk->SetHMPIDmip(mipX,mipY,mipQ,fPhotCnt); //store mip info in any case
134 8 : pTrk->SetHMPIDcluIdx(chId,index+1000*sizeClu); //set index of cluster
135 :
136 8 : if(fPhotCnt<nMinPhotAcc) { //no reconstruction with <=3 photon candidates
137 0 : pTrk->SetHMPIDsignal(kNoPhotAccept); //set the appropriate flag
138 0 : return;
139 : }
140 :
141 8 : fMipPos.Set(mipX,mipY);
142 :
143 : //PATTERN RECOGNITION STARTED:
144 8 : if(fPhotCnt>fParam->MultCut()) fIsWEIGHT = kTRUE; // offset to take into account bkg in reconstruction
145 8 : else fIsWEIGHT = kFALSE;
146 :
147 8 : Int_t iNrec=FlagPhot(HoughResponse(),pCluLst,pTrk); //flag photons according to individual theta ckov with respect to most probable
148 :
149 8 : pTrk->SetHMPIDmip(mipX,mipY,mipQ,iNrec); //store mip info
150 :
151 8 : if(iNrec<nMinPhotAcc){
152 0 : pTrk->SetHMPIDsignal(kNoPhotAccept); //no photon candidates are accepted
153 0 : return;
154 : }
155 :
156 8 : Int_t occupancy = (Int_t)(1000*(nPads/(6.*80.*48.)));
157 :
158 8 : Double_t thetaC = FindRingCkov(pCluLst->GetEntries()); //find the best reconstructed theta Cherenkov
159 : // FindRingGeom(thetaC,2);
160 8 : pTrk->SetHMPIDsignal(thetaC+occupancy); //store theta Cherenkov and chmaber occupancy
161 8 : pTrk->SetHMPIDchi2(fCkovSigma2); //store experimental ring angular resolution squared
162 :
163 8 : DeleteVars();
164 16 : }//CkovAngle()
165 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
166 : Bool_t AliHMPIDRecon::FindPhotCkov(Double_t cluX,Double_t cluY,Double_t &thetaCer,Double_t &phiCer)
167 : {
168 : // Finds Cerenkov angle for this photon candidate
169 : // Arguments: cluX,cluY - position of cadidate's cluster
170 : // Returns: Cerenkov angle
171 :
172 286 : TVector3 dirCkov;
173 :
174 143 : Double_t zRad= -0.5*fParam->RadThick()-0.5*fParam->WinThick(); //z position of middle of RAD
175 143 : TVector3 rad(fTrkPos.X(),fTrkPos.Y(),zRad); //impact point at middle of RAD
176 143 : TVector3 pc(cluX,cluY,0.5*fParam->WinThick()+fParam->GapIdx()); //mip at PC
177 286 : Double_t cluR = TMath::Sqrt((cluX-fTrkPos.X())*(cluX-fTrkPos.X())+
178 143 : (cluY-fTrkPos.Y())*(cluY-fTrkPos.Y()));//ref. distance impact RAD-CLUSTER
179 429 : Double_t phi=(pc-rad).Phi(); //phi of photon
180 :
181 : Double_t ckov1=0;
182 286 : Double_t ckov2=0.75+fTrkDir.Theta(); //start to find theta cerenkov in DRS
183 : const Double_t kTol=0.01;
184 : Int_t iIterCnt = 0;
185 143 : while(1){
186 1730 : if(iIterCnt>=50) return kFALSE;
187 1720 : Double_t ckov=0.5*(ckov1+ckov2);
188 1720 : dirCkov.SetMagThetaPhi(1,ckov,phi);
189 5160 : TVector2 posC=TraceForward(dirCkov); //trace photon with actual angles
190 5160 : Double_t dist=cluR-(posC-fTrkPos).Mod(); //get distance between trial point and cluster position
191 1734 : if(posC.X()==-999) dist = - 999; //total reflection problem
192 1720 : iIterCnt++; //counter step
193 2675 : if (dist> kTol) ckov1=ckov; //cluster @ larger ckov
194 765 : else if(dist<-kTol) ckov2=ckov; //cluster @ smaller ckov
195 : else{ //precision achived: ckov in DRS found
196 138 : dirCkov.SetMagThetaPhi(1,ckov,phi); //
197 414 : Lors2Trs(dirCkov,thetaCer,phiCer); //find ckov (in TRS:the effective Cherenkov angle!)
198 138 : return kTRUE;
199 : }
200 3302 : }
201 143 : }//FindPhotTheta()
202 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
203 : TVector2 AliHMPIDRecon::TraceForward(TVector3 dirCkov)const
204 : {
205 : //Trace forward a photon from (x,y) up to PC
206 : // Arguments: dirCkov photon vector in LORS
207 : // Returns: pos of traced photon at PC
208 :
209 16748 : TVector2 pos(-999,-999);
210 8374 : Double_t thetaCer = dirCkov.Theta();
211 17788 : if(thetaCer > TMath::ASin(1./fParam->GetRefIdx())) return pos; //total refraction on WIN-GAP boundary
212 7334 : Double_t zRad= -0.5*fParam->RadThick()-0.5*fParam->WinThick(); //z position of middle of RAD
213 7334 : TVector3 posCkov(fTrkPos.X(),fTrkPos.Y(),zRad); //RAD: photon position is track position @ middle of RAD
214 22002 : Propagate(dirCkov,posCkov, -0.5*fParam->WinThick()); //go to RAD-WIN boundary
215 7334 : Refract (dirCkov, fParam->GetRefIdx(),fParam->WinIdx()); //RAD-WIN refraction
216 22002 : Propagate(dirCkov,posCkov, 0.5*fParam->WinThick()); //go to WIN-GAP boundary
217 7334 : Refract (dirCkov, fParam->WinIdx(),fParam->GapIdx()); //WIN-GAP refraction
218 22002 : Propagate(dirCkov,posCkov,0.5*fParam->WinThick()+fParam->GapThick()); //go to PC
219 7334 : pos.Set(posCkov.X(),posCkov.Y());
220 : return pos;
221 24082 : }//TraceForward()
222 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
223 : void AliHMPIDRecon::Lors2Trs(TVector3 dirCkov,Double_t &thetaCer,Double_t &phiCer)const
224 : {
225 : //Theta Cerenkov reconstruction
226 : // Arguments: dirCkov photon vector in LORS
227 : // Returns: thetaCer of photon in TRS
228 : // phiCer of photon in TRS
229 : // TVector3 dirTrk;
230 : // dirTrk.SetMagThetaPhi(1,fTrkDir.Theta(),fTrkDir.Phi());
231 : // Double_t thetaCer = TMath::ACos(dirCkov*dirTrk);
232 414 : TRotation mtheta; mtheta.RotateY(-fTrkDir.Theta());
233 414 : TRotation mphi; mphi.RotateZ(-fTrkDir.Phi());
234 138 : TRotation mrot=mtheta*mphi;
235 138 : TVector3 dirCkovTRS;
236 276 : dirCkovTRS=mrot*dirCkov;
237 276 : phiCer = dirCkovTRS.Phi(); //actual value of the phi of the photon
238 276 : thetaCer= dirCkovTRS.Theta(); //actual value of thetaCerenkov of the photon
239 138 : }
240 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
241 : void AliHMPIDRecon::Trs2Lors(TVector3 dirCkov,Double_t &thetaCer,Double_t &phiCer)const
242 : {
243 : //Theta Cerenkov reconstruction
244 : // Arguments: dirCkov photon vector in TRS
245 : // Returns: thetaCer of photon in LORS
246 : // phiCer of photon in LORS
247 19962 : TRotation mtheta; mtheta.RotateY(fTrkDir.Theta());
248 19962 : TRotation mphi; mphi.RotateZ(fTrkDir.Phi());
249 6654 : TRotation mrot=mphi*mtheta;
250 6654 : TVector3 dirCkovLORS;
251 13308 : dirCkovLORS=mrot*dirCkov;
252 13308 : phiCer = dirCkovLORS.Phi(); //actual value of the phi of the photon
253 13308 : thetaCer= dirCkovLORS.Theta(); //actual value of thetaCerenkov of the photon
254 6654 : }
255 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
256 : void AliHMPIDRecon::FindRingGeom(Double_t ckovAng,Int_t level)
257 : {
258 : // Find area covered in the PC acceptance
259 : // Arguments: ckovAng - cerenkov angle
260 : // level - precision in finding area and portion of ring accepted (multiple of 50)
261 : // Returns: area of the ring in cm^2 for given theta ckov
262 :
263 0 : Int_t kN=50*level;
264 : Int_t nPoints = 0;
265 : Double_t area=0;
266 :
267 : Bool_t first=kFALSE;
268 0 : TVector2 pos1;
269 :
270 0 : for(Int_t i=0;i<kN;i++){
271 0 : if(!first) {
272 0 : pos1=TracePhot(ckovAng,Double_t(TMath::TwoPi()*(i+1)/kN)); //find a good trace for the first photon
273 0 : if(pos1.X()==-999) continue; //no area: open ring
274 0 : if(!fParam->IsInside(pos1.X(),pos1.Y(),0)) {
275 0 : pos1 = IntWithEdge(fMipPos,pos1); // find the very first intersection...
276 0 : } else {
277 0 : if(!AliHMPIDParam::IsInDead(pos1.X(),pos1.Y())) nPoints++; //photon is accepted if not in dead zone
278 : }
279 : first=kTRUE;
280 0 : continue;
281 : }
282 0 : TVector2 pos2=TracePhot(ckovAng,Double_t(TMath::TwoPi()*(i+1)/kN)); //trace the next photon
283 0 : if(pos2.X()==-999) continue; //no area: open ring
284 0 : if(!fParam->IsInside(pos2.X(),pos2.Y(),0)) {
285 0 : pos2 = IntWithEdge(fMipPos,pos2);
286 0 : } else {
287 0 : if(!AliHMPIDParam::IsInDead(pos2.X(),pos2.Y())) nPoints++; //photon is accepted if not in dead zone
288 : }
289 0 : area+=TMath::Abs((pos1-fMipPos).X()*(pos2-fMipPos).Y()-(pos1-fMipPos).Y()*(pos2-fMipPos).X()); //add area of the triangle...
290 0 : pos1 = pos2;
291 0 : }
292 : //--- find area and length of the ring;
293 0 : fRingAcc = (Double_t)nPoints/(Double_t)kN;
294 0 : area*=0.5;
295 0 : fRingArea = area;
296 0 : }//FindRingGeom()
297 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
298 : TVector2 AliHMPIDRecon::IntWithEdge(TVector2 p1,TVector2 p2)const
299 : {
300 : // It finds the intersection of the line for 2 points traced as photons
301 : // and the edge of a given PC
302 : // Arguments: 2 points obtained tracing the photons
303 : // Returns: intersection point with detector (PC) edges
304 :
305 0 : Double_t xmin = (p1.X()<p2.X())? p1.X():p2.X();
306 0 : Double_t xmax = (p1.X()<p2.X())? p2.X():p1.X();
307 0 : Double_t ymin = (p1.Y()<p2.Y())? p1.Y():p2.Y();
308 0 : Double_t ymax = (p1.Y()<p2.Y())? p2.Y():p1.Y();
309 :
310 0 : Double_t m = TMath::Tan((p2-p1).Phi());
311 0 : TVector2 pint;
312 : //intersection with low X
313 0 : pint.Set((Double_t)(p1.X() + (0-p1.Y())/m),0.);
314 0 : if(pint.X()>=0 && pint.X()<=fParam->SizeAllX() &&
315 0 : pint.X()>=xmin && pint.X()<=xmax &&
316 0 : pint.Y()>=ymin && pint.Y()<=ymax) return pint;
317 : //intersection with high X
318 0 : pint.Set((Double_t)(p1.X() + (fParam->SizeAllY()-p1.Y())/m),(Double_t)(fParam->SizeAllY()));
319 0 : if(pint.X()>=0 && pint.X()<=fParam->SizeAllX() &&
320 0 : pint.X()>=xmin && pint.X()<=xmax &&
321 0 : pint.Y()>=ymin && pint.Y()<=ymax) return pint;
322 : //intersection with left Y
323 0 : pint.Set(0.,(Double_t)(p1.Y() + m*(0-p1.X())));
324 0 : if(pint.Y()>=0 && pint.Y()<=fParam->SizeAllY() &&
325 0 : pint.Y()>=ymin && pint.Y()<=ymax &&
326 0 : pint.X()>=xmin && pint.X()<=xmax) return pint;
327 : //intersection with righ Y
328 0 : pint.Set((Double_t)(fParam->SizeAllX()),(Double_t)(p1.Y() + m*(fParam->SizeAllX()-p1.X())));
329 0 : if(pint.Y()>=0 && pint.Y()<=fParam->SizeAllY() &&
330 0 : pint.Y()>=ymin && pint.Y()<=ymax &&
331 0 : pint.X()>=xmin && pint.X()<=xmax) return pint;
332 0 : return p1;
333 0 : }//IntWithEdge()
334 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
335 : Double_t AliHMPIDRecon::FindRingCkov(Int_t)
336 : {
337 : // 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
338 : // collecting errors for all single Ckov candidates thetas. (Assuming they are independent)
339 : // Arguments: iNclus- total number of clusters in chamber for background estimation
340 : // Return: best estimation of track Theta ckov
341 :
342 : Double_t wei = 0.;
343 : Double_t weightThetaCerenkov = 0.;
344 :
345 : Double_t ckovMin=9999.,ckovMax=0.;
346 : Double_t sigma2 = 0; //to collect error squared for this ring
347 :
348 300 : for(Int_t i=0;i<fPhotCnt;i++){//candidates loop
349 138 : if(fPhotFlag[i] == 2){
350 97 : if(fPhotCkov[i]<ckovMin) ckovMin=fPhotCkov[i]; //find max and min Theta ckov from all candidates within probable window
351 101 : if(fPhotCkov[i]>ckovMax) ckovMax=fPhotCkov[i];
352 76 : weightThetaCerenkov += fPhotCkov[i]*fPhotWei[i];
353 76 : wei += fPhotWei[i]; //collect weight as sum of all candidate weghts
354 :
355 76 : sigma2 += 1./fParam->Sigma2(fTrkDir.Theta(),fTrkDir.Phi(),fPhotCkov[i],fPhotPhi[i]);
356 76 : }
357 : }//candidates loop
358 :
359 16 : if(sigma2>0) fCkovSigma2=1./sigma2;
360 0 : else fCkovSigma2=1e10;
361 :
362 16 : if(wei != 0.) weightThetaCerenkov /= wei; else weightThetaCerenkov = 0.;
363 8 : return weightThetaCerenkov;
364 : }//FindCkovRing()
365 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
366 : Int_t AliHMPIDRecon::FlagPhot(Double_t ckov,TClonesArray *pCluLst, AliESDtrack *pTrk)
367 : {
368 : // Flag photon candidates if their individual ckov angle is inside the window around ckov angle returned by HoughResponse()
369 : // Arguments: ckov- value of most probable ckov angle for track as returned by HoughResponse()
370 : // Returns: number of photon candidates happened to be inside the window
371 :
372 : // Photon Flag: Flag = 0 initial set;
373 : // Flag = 1 good candidate (charge compatible with photon);
374 : // Flag = 2 photon used for the ring;
375 :
376 16 : Int_t steps = (Int_t)((ckov )/ fDTheta); //how many times we need to have fDTheta to fill the distance between 0 and thetaCkovHough
377 :
378 8 : Double_t tmin = (Double_t)(steps - 1)*fDTheta;
379 8 : Double_t tmax = (Double_t)(steps)*fDTheta;
380 8 : Double_t tavg = 0.5*(tmin+tmax);
381 :
382 8 : tmin = tavg - 0.5*fWindowWidth; tmax = tavg + 0.5*fWindowWidth;
383 :
384 : Int_t iInsideCnt = 0; //count photons which Theta ckov inside the window
385 292 : for(Int_t i=0;i<fPhotCnt;i++){//photon candidates loop
386 138 : fPhotFlag[i] = 0;
387 260 : if(fPhotCkov[i] >= tmin && fPhotCkov[i] <= tmax) {
388 76 : fPhotFlag[i]=2;
389 76 : AddObjectToFriends(pCluLst,i,pTrk);
390 76 : iInsideCnt++;
391 76 : }
392 : }
393 :
394 8 : return iInsideCnt;
395 :
396 : }//FlagPhot()
397 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
398 : void AliHMPIDRecon::AddObjectToFriends(TClonesArray *pCluLst, Int_t photonIndex, AliESDtrack *pTrk)
399 : {
400 : // Add AliHMPIDcluster object to ESD friends
401 :
402 152 : AliHMPIDCluster *pClu=(AliHMPIDCluster*)pCluLst->UncheckedAt(fPhotClusIndex[photonIndex]);
403 76 : AliHMPIDCluster *pClus = new AliHMPIDCluster(*pClu);
404 76 : pClus->SetChi2(fPhotCkov[photonIndex]);
405 76 : pTrk->AddCalibObject(pClus);
406 76 : }
407 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
408 : TVector2 AliHMPIDRecon::TracePhot(Double_t ckovThe,Double_t ckovPhi)const
409 : {
410 : // Trace a single Ckov photon from emission point somewhere in radiator up to photocathode taking into account ref indexes of materials it travereses
411 : // Arguments: ckovThe,ckovPhi- photon ckov angles in TRS, [rad]
412 : // Returns: distance between photon point on PC and track projection
413 :
414 13308 : Double_t theta,phi;
415 6654 : TVector3 dirTRS,dirLORS;
416 6654 : dirTRS.SetMagThetaPhi(1,ckovThe,ckovPhi); //photon in TRS
417 19962 : Trs2Lors(dirTRS,theta,phi);
418 6654 : dirLORS.SetMagThetaPhi(1,theta,phi); //photon in LORS
419 19962 : return TraceForward(dirLORS); //now foward tracing
420 6654 : }//TracePhot()
421 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
422 : void AliHMPIDRecon::Propagate(const TVector3 dir,TVector3 &pos,Double_t z)const
423 : {
424 : // Finds an intersection point between a line and XY plane shifted along Z.
425 : // Arguments: dir,pos - vector along the line and any point of the line
426 : // z - z coordinate of plain
427 : // Returns: none
428 : // On exit: pos is the position if this intesection if any
429 44010 : static TVector3 nrm(0,0,1);
430 22002 : TVector3 pnt(0,0,z);
431 :
432 22002 : TVector3 diff=pnt-pos;
433 66006 : Double_t sint=(nrm*diff)/(nrm*dir);
434 44004 : pos+=sint*dir;
435 22002 : }//Propagate()
436 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
437 : void AliHMPIDRecon::Refract(TVector3 &dir,Double_t n1,Double_t n2)const
438 : {
439 : // Refract direction vector according to Snell law
440 : // Arguments:
441 : // n1 - ref idx of first substance
442 : // n2 - ref idx of second substance
443 : // Returns: none
444 : // On exit: dir is new direction
445 29336 : Double_t sinref=(n1/n2)*TMath::Sin(dir.Theta());
446 14668 : if(TMath::Abs(sinref)>1.) dir.SetXYZ(-999,-999,-999);
447 14668 : else dir.SetTheta(TMath::ASin(sinref));
448 14668 : }//Refract()
449 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
450 : Double_t AliHMPIDRecon::HoughResponse()
451 : {
452 : //
453 : // fIdxMip = mipId;
454 :
455 : //
456 : Double_t kThetaMax=0.75;
457 16 : Int_t nChannels = (Int_t)(kThetaMax/fDTheta+0.5);
458 8 : TH1D *phots = new TH1D("Rphot" ,"phots" ,nChannels,0,kThetaMax);
459 8 : TH1D *photsw = new TH1D("RphotWeighted" ,"photsw" ,nChannels,0,kThetaMax);
460 8 : TH1D *resultw = new TH1D("resultw","resultw" ,nChannels,0,kThetaMax);
461 8 : Int_t nBin = (Int_t)(kThetaMax/fDTheta);
462 8 : Int_t nCorrBand = (Int_t)(fWindowWidth/(2*fDTheta));
463 :
464 292 : for (Int_t i=0; i< fPhotCnt; i++){//photon cadidates loop
465 304 : Double_t angle = fPhotCkov[i]; if(angle<0||angle>kThetaMax) continue;
466 110 : phots->Fill(angle);
467 110 : Int_t bin = (Int_t)(0.5+angle/(fDTheta));
468 : Double_t weight=1.;
469 110 : if(fIsWEIGHT){
470 0 : Double_t lowerlimit = ((Double_t)bin)*fDTheta - 0.5*fDTheta; Double_t upperlimit = ((Double_t)bin)*fDTheta + 0.5*fDTheta;
471 0 : FindRingGeom(lowerlimit);
472 0 : Double_t areaLow = GetRingArea();
473 0 : FindRingGeom(upperlimit);
474 0 : Double_t areaHigh = GetRingArea();
475 0 : Double_t diffArea = areaHigh - areaLow;
476 0 : if(diffArea>0) weight = 1./diffArea;
477 0 : }
478 110 : photsw->Fill(angle,weight);
479 110 : fPhotWei[i]=weight;
480 110 : }//photon candidates loop
481 :
482 12000 : for (Int_t i=1; i<=nBin;i++){
483 5992 : Int_t bin1= i-nCorrBand;
484 5992 : Int_t bin2= i+nCorrBand;
485 6168 : if(bin1<1) bin1=1;
486 6168 : if(bin2>nBin)bin2=nBin;
487 5992 : Double_t sumPhots=phots->Integral(bin1,bin2);
488 11314 : if(sumPhots<3) continue; // if less then 3 photons don't trust to this ring
489 670 : Double_t sumPhotsw=photsw->Integral(bin1,bin2);
490 797 : if((Double_t)((i+0.5)*fDTheta)>0.7) continue;
491 543 : resultw->Fill((Double_t)((i+0.5)*fDTheta),sumPhotsw);
492 543 : }
493 : // evaluate the "BEST" theta ckov as the maximum value of histogramm
494 8 : Double_t *pVec = resultw->GetArray();
495 8 : Int_t locMax = TMath::LocMax(nBin,pVec);
496 48 : delete phots;delete photsw;delete resultw; // Reset and delete objects
497 :
498 8 : return (Double_t)(locMax*fDTheta+0.5*fDTheta); //final most probable track theta ckov
499 0 : }//HoughResponse()
500 : //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
501 : Double_t AliHMPIDRecon::FindRingExt(Double_t ckov,Int_t ch,Double_t xPc,Double_t yPc,Double_t thRa,Double_t phRa)
502 : {
503 : // To find the acceptance of the ring even from external inputs.
504 : //
505 : //
506 0 : Double_t xRa = xPc - (fParam->RadThick()+fParam->WinThick()+fParam->GapThick())*TMath::Cos(phRa)*TMath::Tan(thRa); //just linear extrapolation back to RAD
507 0 : Double_t yRa = yPc - (fParam->RadThick()+fParam->WinThick()+fParam->GapThick())*TMath::Sin(phRa)*TMath::Tan(thRa);
508 :
509 : Int_t nStep = 500;
510 : Int_t nPhi = 0;
511 :
512 0 : Int_t ipc,ipadx,ipady;
513 :
514 0 : if(ckov>0){
515 0 : SetTrack(xRa,yRa,thRa,phRa);
516 0 : for(Int_t j=0;j<nStep;j++){
517 0 : TVector2 pos; pos=TracePhot(ckov,j*TMath::TwoPi()/(Double_t)(nStep-1));
518 0 : if(fParam->IsInDead(pos.X(),pos.Y())) continue;
519 0 : fParam->Lors2Pad(pos.X(),pos.Y(),ipc,ipadx,ipady);
520 0 : ipadx+=(ipc%2)*fParam->kPadPcX;
521 0 : ipady+=(ipc/2)*fParam->kPadPcY;
522 0 : if(ipadx<0 || ipady>160 || ipady<0 || ipady>144 || ch<0 || ch>6) continue;
523 0 : if(fParam->IsDeadPad(ipadx,ipady,ch)) continue;
524 0 : nPhi++;
525 0 : }//point loop
526 0 : return ((Double_t)nPhi/(Double_t)nStep);
527 : }//if
528 0 : return -1;
529 0 : }
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