HMPID/AliHMPIDReconHTA.cxx

   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.              *
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  11  * appear in the supporting documentation. The authors make no claims     *
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  13  * provided "as is" without express or implied warranty.                  *
  14  **************************************************************************/
  15
  16 //////////////////////////////////////////////////////////////////////////
  17 //                                                                      //
  18 // AliHMPIDReconHTA                                                         //
  19 //                                                                      //
  20 // HMPID class to perfom pattern recognition based on Hough transfrom    //
  21 // for single chamber                                                   //
  22 //////////////////////////////////////////////////////////////////////////
  23
  24 #include "AliHMPIDReconHTA.h"//class header
  25 #include "AliHMPIDCluster.h" //CkovHiddenTrk()
  26 #include "AliHMPIDRecon.h"   //FunMinPhot()
  27 #include <TFile.h>           //Database()
  28 #include <TMinuit.h>         //FitFree()
  29 #include <TClonesArray.h>    //CkovHiddenTrk()
  30 #include <AliESDtrack.h>     //CkovHiddenTrk()
  31 #include <TH2F.h>            //InitDatabase()
  32 #include <TGraph.h>          //ShapeModel()
  33 #include <TSpline.h>         //ShapeModel()
  34 #include "TStopwatch.h"      //
  35
  36 TH2F* AliHMPIDReconHTA::fgDatabase = new TH2F("deconv","database;d1;d2;thC+1000*thTrk",500,0,50,150,0,15);
  37
  38
  39 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  40 AliHMPIDReconHTA::AliHMPIDReconHTA():
  41   TTask("RichRec","RichPat"),
  42   fMipX(-999),
  43   fMipY(-999),
  44   fMipQ(-999),
  45   fRadX(-999),
  46   fRadY(-999),
  47   fIdxMip(0),
  48   fNClu(0),
  49   fXClu(0),
  50   fYClu(0),
  51   fClCk(0),
  52   fThTrkFit(-999),
  53   fPhTrkFit(-999),
  54   fCkovFit(-999),
  55   fCkovSig2(0),
  56   fParam(AliHMPIDParam::Instance())
  57 {
  58 //..
  59 //hidden algorithm
  60 //..
  61   fParam->SetRefIdx(fParam->MeanIdxRad()); // initialization of ref index to a default one
  62   if(fgDatabase->GetEntries()<1) InitDatabase();
  63 }
  64 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  65 AliHMPIDReconHTA::~AliHMPIDReconHTA()
  66 {
  67   DeleteVars();
  68 }
  69 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  70 void AliHMPIDReconHTA::InitVars(Int_t n)
  71 {
  72 //..
  73 //Init some variables
  74 //..
  75   fXClu = new Double_t[n];
  76   fYClu = new Double_t[n];
  77   fClCk = new Bool_t[n];
  78   for(Int_t i=0;i<n;i++) fClCk[i] = kTRUE;
  79 //
  80 }
  81 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  82 void AliHMPIDReconHTA::DeleteVars()const
  83 {
  84 //..
  85 //Delete variables
  86 //..
  87   if(fXClu) delete fXClu;
  88   if(fYClu) delete fYClu;
  89   if(fClCk) delete fClCk;
  90 }
  91 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  92 Bool_t AliHMPIDReconHTA::CkovHiddenTrk(AliESDtrack *pTrk,TClonesArray *pCluLst,Int_t index, Double_t nmean)
  93 {
  94 // Pattern recognition method without any infos from tracking:HTA (Hidden Track Algorithm)...
  95 // The method finds in the chmuber the cluster with the highest charge
  96 // compatibile with a MIP, then the strategy is applied
  97 // Arguments:  pTrk     - pointer to ESD track
  98 //             pCluLs   - list of clusters for a given chamber
  99 //             pNmean   - pointer to ref. index
 100 //             pQthre   - pointer to qthre
 101 //   Returns:           - 0=ok,1=not fitted
 102
 103   AliHMPIDParam *pParam = AliHMPIDParam::Instance();
 104
 105   if(!CluPreFilter(pCluLst)) return kFALSE;
 106
 107   Int_t nCh=0;
 108   Int_t sizeClu=0;
 109
 110   fNClu = pCluLst->GetEntriesFast();
 111
 112   for (Int_t iClu=0;iClu<fNClu;iClu++){                                                       //clusters loop
 113     AliHMPIDCluster *pClu=(AliHMPIDCluster*)pCluLst->UncheckedAt(iClu);                       //get pointer to current cluster
 114     fXClu[iClu] = pClu->X();fYClu[iClu] = pClu->Y();                                          //store x,y for fitting procedure
 115     fClCk[iClu] = kTRUE;                                                                      //all cluster are accepted at this stage to be reconstructed
 116
 117     if(iClu == index) {
 118
 119       fMipX = pClu->X();
 120       fMipY = pClu->Y();
 121       fMipQ = pClu->Q();
 122       sizeClu = pClu->Size();
 123       nCh = pClu->Ch();
 124       fClCk[index] = kFALSE;
 125       fIdxMip = index;
 126  //    Printf(" n. %d x %f y %f Q %f",iClu,pClu->X(),pClu->Y(),pClu->Q());
 127     }
 128   }//clusters loop
 129
 130   pParam->SetRefIdx(nmean);
 131
 132   if(!DoRecHiddenTrk()) {
 133     pTrk->SetHMPIDsignal(pParam->kNoPhotAccept);
 134     return kFALSE;
 135   }                                                                           //Do track and ring reconstruction,if problems returns 1
 136
 137   pTrk->SetHMPIDtrk(fRadX,fRadY,fThTrkFit,fPhTrkFit);                                        //store track intersection info
 138   pTrk->SetHMPIDmip(fMipX,fMipY,(Int_t)fMipQ,fNClu);                                         //store mip info
 139   pTrk->SetHMPIDcluIdx(nCh,fIdxMip+1000*sizeClu);                                            //set cham number, index of cluster + cluster size
 140   pTrk->SetHMPIDsignal(fCkovFit);                                                            //find best Theta ckov for ring i.e. track
 141   pTrk->SetHMPIDchi2(fCkovSig2);                                                             //errors squared
 142 //    Printf(" n clusters tot %i accepted %i",pCluLst->GetEntriesFast(),fNClu);
 143 //    Printf("CkovHiddenTrk: thetaC %f th %f ph %f",fCkovFit,fThTrkFit,fPhTrkFit);
 144
 145   return kTRUE;
 146
 147 }//CkovHiddenTrk()
 148 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 149 Bool_t AliHMPIDReconHTA::DoRecHiddenTrk()
 150 {
 151 // Pattern recognition method without any infos from tracking...
 152 // First a preclustering filter to avoid part of the noise
 153 // Then only ellipsed-rings are fitted (no possibility,
 154 // for the moment, to reconstruct very inclined tracks)
 155 // Finally a fitting with (th,ph) free, starting by very close values
 156 // previously evaluated.
 157 // Arguments:   none
 158 //   Returns:   none
 159   Double_t thTrkRec,phiTrkRec,thetaCRec;
 160
 161   if(!FindShape(thTrkRec,phiTrkRec,thetaCRec)) return kFALSE;
 162
 163   if(!FitFree(thTrkRec,phiTrkRec)) {return kFALSE;}
 164
 165   return kTRUE;
 166 }//DoRecHiddenTrk()
 167 /*
 168 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 169 Bool_t AliHMPIDReconHTA::DoRecHiddenTrk(TClonesArray *pCluLst)
 170 {
 171 // Pattern recognition method without any infos from tracking...
 172 // First a preclustering filter to avoid part of the noise
 173 // Then only ellipsed-rings are fitted (no possibility,
 174 // for the moment, to reconstruct very inclined tracks)
 175 // Finally a fitting with (th,ph) free, starting by very close values
 176 // previously evaluated.
 177 // Arguments:   none
 178 //   Returns:   none
 179   Double_t thTrkRec,phiTrkRec,thetaCRec;
 180
 181   if(!FindShape(thTrkRec,phiTrkRec,thetaCRec)) return kFALSE;
 182
 183 //  Printf("thTrkRec %f phiTrkRec %f ThetaCRec %f",thTrkRec*TMath::RadToDeg(),phiTrkRec*TMath::RadToDeg(),thetaCRec*TMath::RadToDeg());
 184   Int_t nClTmp1 = pCluLst->GetEntriesFast()-1;  //minus MIP...
 185   Int_t nClTmp2 = 0;
 186
 187   while(nClTmp1 != nClTmp2){
 188     SetNClu(pCluLst->GetEntriesFast());
 189     if(!FitFree(thTrkRec,phiTrkRec)) {return kFALSE;}
 190     nClTmp2 = NClu();
 191     if(nClTmp2!=nClTmp1) {nClTmp1=nClTmp2;nClTmp2=0;}
 192   }
 193
 194   fNClu = nClTmp2;
 195   return kTRUE;
 196 }//DoRecHiddenTrk()
 197 */
 198 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 199 Bool_t AliHMPIDReconHTA::CluPreFilter(TClonesArray *pCluLst)
 200 {
 201 // Pre-filter of bkg clusters
 202 // Arguments:    pSluLst  -  List of the clusters for a given chamber
 203 //   Returns:    status   -  TRUE if filtering leaves enough photons, FALSE if not
 204 //
 205   Int_t nClusTot = pCluLst->GetEntriesFast();
 206   if(nClusTot<4||nClusTot>100) {
 207     return kFALSE;
 208   } else {
 209     InitVars(nClusTot);
 210     return kTRUE;
 211   }
 212 }
 213 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 214 Bool_t AliHMPIDReconHTA::FindShape(Double_t &thTrkRec,Double_t &phiTrkRec,Double_t &thetaCRec)
 215 {
 216 // Finds the estimates for phi and theta of the track and the ThetaCerenkov
 217 // by using a database of the shapes of the rings
 218 // Arguments:   none
 219 //   Returns:   thTrkRec  - estimate of theta track
 220 //              phiTrkRec - estimate of phi   track
 221 //              thetaCRec - estimate of ThetaCerenkov
 222 //              status    - TRUE if a good solution is found, FALSE if not
 223
 224   Double_t *phiphot = new Double_t[fNClu];
 225   Double_t *dist    = new Double_t[fNClu];
 226   Int_t    *indphi  = new    Int_t[fNClu];
 227
 228   Bool_t status;
 229
 230 // Sort in phi angle...
 231 //  Printf(" mipX %f mipy %f",fMipX,fMipY);
 232   for(Int_t i=0;i<fNClu;i++) {
 233     if(!fClCk[i]) {
 234       phiphot[i] = 999.;
 235       dist[i] = 999.;
 236       continue;
 237     }
 238     phiphot[i] = (TMath::ATan2(fMipY-fYClu[i],fMipX-fXClu[i])+TMath::Pi())*TMath::RadToDeg();
 239     dist[i]=TMath::Sqrt((fMipX-fXClu[i])*(fMipX-fXClu[i])+(fMipY-fYClu[i])*(fMipY-fYClu[i]));
 240 //    Printf(" n.%3i  phiphot %f dist %f check %i",i,phiphot[i],dist[i],fClCk[i]);
 241   }
 242
 243   TMath::Sort(fNClu,phiphot,indphi,kFALSE);
 244
 245 // Purify with a truncated mean;
 246   Int_t np=0;
 247   Double_t dMean  = 0;
 248   Double_t dMean2 = 0;
 249   for(Int_t i=0;i<fNClu;i++) {
 250     if(!fClCk[indphi[i]]) continue;                                                  // Check if a good photon candidate or not
 251     dMean +=dist[indphi[i]];
 252     dMean2+=dist[indphi[i]]*dist[indphi[i]];
 253     np++;
 254   }
 255
 256   dMean  /=(Double_t)np;
 257   dMean2 /=(Double_t)np;
 258   Double_t rms = TMath::Sqrt(dMean2 - dMean*dMean);
 259
 260   for(Int_t i=0;i<fNClu;i++) {
 261     if(!fClCk[indphi[i]]) continue;                                                  // Check if a good photon candidate or not
 262     if(TMath::Abs(dMean-dist[indphi[i]]) > 2*rms) {
 263       fClCk[indphi[i]] = kFALSE;
 264       continue;
 265     }
 266   }
 267
 268 //
 269 //  purify vectors for good photon candidates
 270 //
 271   Int_t npeff=0;
 272   Double_t *phiphotP = new Double_t[fNClu+1];
 273   Double_t *distP    = new Double_t[fNClu+1];
 274   for(Int_t i=0;i<fNClu;i++) {
 275     if(!fClCk[indphi[i]]) continue;                                                  // Check if a good photon candidate or not
 276     phiphotP[npeff] = phiphot[indphi[i]];
 277     distP[npeff]    = dist[indphi[i]];
 278 //    Printf("n. %2i phi %f dist %f",npeff,phiphotP[npeff],distP[npeff]);
 279     npeff++;
 280   }
 281
 282   delete [] phiphot;
 283   delete [] dist;
 284   delete [] indphi;
 285
 286   if(npeff<3) {
 287     delete [] phiphotP;
 288     delete [] distP;
 289     return kFALSE;
 290   }
 291
 292 //  for(Int_t i=0;i<npeff;i++) {Printf(" n. %d phiphot %f dist %f",i,phiphotP[i],distP[i]);}
 293
 294   Double_t xA,xB;
 295   status = kFALSE;
 296   if(ShapeModel(npeff,phiphotP,distP,xA,xB,phiTrkRec)) {
 297
 298 //    Printf("FindShape: phi start %f xA %f yA %f",phiTrkRec*TMath::RadToDeg(),xA,xB);
 299     if(xA < 50 && xB < 15) {                     // limits of the Database. See TH2F in InitDatabase()
 300
 301       Int_t bin = fgDatabase->FindBin(xA,xB);
 302       if(bin>0) {
 303         Int_t compact = (Int_t)fgDatabase->GetBinContent(bin);
 304         thetaCRec =  (Double_t)(compact%1000);
 305         thTrkRec  =  (Double_t)(compact/1000);
 306
 307         thTrkRec *= TMath::DegToRad();
 308         thetaCRec *= TMath::DegToRad();
 309
 310     //    Printf("FindShape: xA %f xB %f compact %d thTrk %f thC %f",xA,xB,compact,thTrkRec*TMath::RadToDeg(),thetaCRec*TMath::RadToDeg());
 311
 312         status = kTRUE;
 313       }
 314     }
 315   }
 316
 317   delete [] phiphotP;
 318   delete [] distP;
 319
 320   return status;
 321 }
 322 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 323 Bool_t AliHMPIDReconHTA::ShapeModel(Int_t np,Double_t *phiphot,Double_t *dist,Double_t &xA,Double_t &xB,Double_t &phiStart)
 324 {
 325 // Find a Spline curve to define dist. vs. phi angle
 326 // in order to estimate the phi of the track
 327 // Arguments:   np     - # points corresponding to # photon candidates
 328 //             dist    - distance of each photon from MIP
 329 //             phiphot - phi of the photon in the DRS
 330 //   Returns:  xA      - min. distance from MIP
 331 //             xB      - dist. from mip perpedicular to the major axis
 332 //             phiStart- estimate of the track phi
 333
 334   TGraph *phigr = new TGraph(np,phiphot,dist);
 335   TSpline3 *sphi = new TSpline3("sphi",phigr);
 336   if(!sphi) {Printf("Spline not created!Bye.");return kFALSE;}
 337
 338   Int_t locMin = TMath::LocMin(np,dist);
 339   Int_t locMax = TMath::LocMax(np,dist);
 340
 341   Double_t minX = phiphot[locMin];
 342 //  Double_t minY =    dist[locMin];
 343   Double_t maxX = phiphot[locMax];
 344 //  Double_t maxY =    dist[locMax];
 345
 346   Int_t ip[3] = {-1,0,1};
 347   if(locMin==0   ) {ip[0]= 0;ip[1]= 1;ip[2]= 2;}
 348   if(locMin==np-1) {ip[0]=-2;ip[1]=-1;ip[2]= 0;}
 349
 350   Double_t minXf = VertParab(phiphot[locMin+ip[0]],dist[locMin+ip[0]],
 351                              phiphot[locMin+ip[1]],dist[locMin+ip[1]],
 352                              phiphot[locMin+ip[2]],dist[locMin+ip[2]]);
 353   if(minXf< phiphot[locMin+ip[0]] || minXf > phiphot[locMin+ip[2]]) minXf = minX;
 354
 355   ip[0]=-1;ip[1]=0;ip[2]=1;
 356   if(locMax==0   ) {ip[0]= 0;ip[1]= 1;ip[2]= 2;}
 357   if(locMax==np-1) {ip[0]=-2;ip[1]=-1;ip[2]= 0;}
 358
 359   Double_t maxXf = VertParab(phiphot[locMax+ip[0]],dist[locMax+ip[0]],
 360                              phiphot[locMax+ip[1]],dist[locMax+ip[1]],
 361                              phiphot[locMax+ip[2]],dist[locMax+ip[2]]);
 362   if(maxXf< phiphot[locMax+ip[0]] || maxXf > phiphot[locMax+ip[2]]) maxXf = maxX;
 363
 364 //
 365   if(TMath::Abs(maxXf-minXf)>30) {
 366     xA = sphi->Eval(minXf);
 367     if(xA < 0) xA = dist[sphi->FindX(xA)];
 368     xB = sphi->Eval(minXf-90);
 369     if(xB < 0) xB = dist[sphi->FindX(xB)];
 370     phiStart = minXf-180;  //open ring or acceptance effect...so believe to min phi angle!
 371   } else {
 372     phiStart = 0.5*(maxXf-180+minXf);
 373     xA = sphi->Eval(phiStart+180);
 374     if(xA < 0) xA = dist[sphi->FindX(xA)];
 375     xB = sphi->Eval(phiStart+90);
 376     if(xB < 0) xB = dist[sphi->FindX(xB)];
 377   }
 378   //
 379 //  Printf("ShapeModel: phiStart %f xA %f xB %f",phiStart,xA,xB);
 380
 381   phiStart*=TMath::DegToRad();
 382
 383   return kTRUE;
 384 }
 385 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 386 Double_t AliHMPIDReconHTA::VertParab(Double_t x1,Double_t y1,Double_t x2, Double_t y2, Double_t x3, Double_t y3)const
 387 {
 388 // It uses parabola from 3 points to evaluate the x-coord of the parab
 389 // Arguments:    xi,yi - points
 390 //   Returns:    x-coord of the vertex
 391
 392   Double_t a = ((x1-x3)*(y1-y2)-(x1-x2)*(y1-y3))/((x1*x1-x2*x2)*(x1-x3)-(x1*x1-x3*x3)*(x1-x2));
 393   Double_t b = (y1-y2 - a*(x1*x1-x2*x2))/(x1-x2);
 394 //  Double_t c = y1 - a*x1*x1-b*x1;
 395   return -0.5*b/a;
 396 }
 397 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 398 Bool_t AliHMPIDReconHTA::FitFree(Double_t thTrkRec,Double_t phiTrkRec)
 399 {
 400 // Fit performed by minimizing RMS/sqrt(n) of the
 401 // photons reconstructed. First phi is fixed and theta
 402 // is fouond, then (th,ph) of the track
 403 // as free parameters
 404 // Arguments:    PhiRec phi of the track
 405 //   Returns:    none
 406
 407   TMinuit *pMinuit = new TMinuit(2);
 408   pMinuit->mncler();
 409   gMinuit->SetObjectFit((TObject*)this);  gMinuit->SetFCN(AliHMPIDReconHTA::FunMinPhot);  //set fit function
 410   Double_t aArg=-1,parStep,parLow,parHigh;     Int_t iErrFlg;                 //tmp vars for TMinuit
 411   Double_t d1,d2,d3;
 412   TString sName;
 413   Double_t th,ph;
 414
 415   pMinuit->mnexcm("SET PRI",&aArg,1,iErrFlg);                                          //suspend all printout from TMinuit
 416   pMinuit->mnexcm("SET NOW",&aArg,0,iErrFlg);
 417
 418   if(thTrkRec==0) thTrkRec = 3.*TMath::DegToRad();    // not to start from the edge...
 419
 420   pMinuit->mnparm(0," thTrk  ",thTrkRec ,parStep=0.01,parLow=0,parHigh=TMath::PiOver4(),iErrFlg);
 421   pMinuit->mnparm(1," phiTrk ",phiTrkRec,parStep=0.01,parLow=0,parHigh=TMath::TwoPi(),iErrFlg);
 422
 423   pMinuit->FixParameter(1);
 424   pMinuit->mnexcm("SIMPLEX" ,&aArg,0,iErrFlg);
 425   pMinuit->mnexcm("MIGRAD"  ,&aArg,0,iErrFlg);
 426   pMinuit->Release(1);
 427   pMinuit->mnexcm("MIGRAD"  ,&aArg,0,iErrFlg);
 428
 429   pMinuit->mnpout(0,sName,th,d1,d2,d3,iErrFlg);
 430   pMinuit->mnpout(1,sName,ph,d1,d2,d3,iErrFlg);
 431
 432   Double_t f,par[2];
 433   Double_t *grad=0x0;
 434   par[0] = th;par[1] = ph;
 435   pMinuit->Eval(2,grad,f,par,3);
 436
 437 //  Printf("FitFree: theta %f phi %f",th,ph);
 438
 439   SetTrkFit(th,ph);
 440   return kTRUE;
 441 }
 442 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 443 void AliHMPIDReconHTA::FunMinPhot(Int_t &/* */,Double_t* /* */,Double_t &f,Double_t *par,Int_t iflag)
 444 {
 445 // Minimization function to find best track and thetaC parameters
 446 // Arguments:    f = function value to minimize
 447 //             par = list of parameter to find
 448 //           iflag = flag status. See Minuit instructions
 449 //   Returns:    none
 450 //
 451 // Note: it is necessary to call an instance of AlihMPIDParam. Not possible to use fParam
 452 // because of the static instantiation of the function in Minuit
 453
 454   AliHMPIDParam *pParam=AliHMPIDParam::Instance();
 455   AliHMPIDReconHTA *pRecHTA=(AliHMPIDReconHTA*)gMinuit->GetObjectFit();
 456   AliHMPIDRecon pRec;
 457   Double_t sizeCh = 0.5*pParam->RadThick()+pParam->WinThick()+pParam->GapThick();
 458   Double_t thTrk = par[0];
 459   Double_t phTrk = par[1];
 460   Double_t xrad = pRecHTA->MipX() - sizeCh*TMath::Tan(thTrk)*TMath::Cos(phTrk);
 461   Double_t yrad = pRecHTA->MipY() - sizeCh*TMath::Tan(thTrk)*TMath::Sin(phTrk);
 462   pRecHTA->SetRadXY(xrad,yrad);
 463   pRec.SetTrack(xrad,yrad,thTrk,phTrk);
 464
 465   Double_t meanCkov =0;
 466   Double_t meanCkov2=0;
 467   Double_t thetaCer,phiCer;
 468   Int_t nClAcc = 0;
 469   Int_t nClTot=pRecHTA->NClu();
 470
 471   for(Int_t i=0;i<nClTot;i++) {
 472     if(!(pRecHTA->ClCk(i))) continue;
 473     pRec.FindPhotCkov(pRecHTA->XClu(i),pRecHTA->YClu(i),thetaCer,phiCer);
 474     meanCkov  += thetaCer;
 475     meanCkov2 += thetaCer*thetaCer;
 476     nClAcc++;
 477   }
 478   if(nClAcc==0) {f=999;return;}
 479   meanCkov  /=(Double_t)nClAcc;
 480   meanCkov2 /=(Double_t)nClAcc;
 481   Double_t rms = TMath::Sqrt(TMath::Abs(meanCkov2 - meanCkov*meanCkov));
 482   f = rms/TMath::Sqrt((Double_t)nClAcc);
 483
 484   if(iflag==3) {
 485 /*
 486     Printf("FunMinPhot before: photons candidates %i used %i",nClTot,nClAcc);
 487     nClAcc = 0;
 488     Double_t meanCkov1=0;
 489     Double_t meanCkov2=0;
 490     for(Int_t i=0;i<nClTot;i++) {
 491       if(!(pRec->ClCk(i))) continue;
 492       pRec->FindPhotCkov(pRec->XClu(i),pRec->YClu(i),thetaCer,phiCer);
 493       if(TMath::Abs(thetaCer-meanCkov)<2*rms) {
 494         meanCkov1 += thetaCer;
 495         meanCkov2 += thetaCer*thetaCer;
 496         nClAcc++;
 497       } else pRec->SetClCk(i,kFALSE);
 498     }
 499     meanCkov1/=nClAcc;
 500     Double_t rms2 = (meanCkov2 - meanCkov*meanCkov*nClAcc)/nClAcc;
 501     Printf("FunMinPhot after: photons candidates %i used %i thetaCer %f",nClTot,nClAcc,meanCkov1);
 502     pRec->SetCkovFit(meanCkov1);
 503     pRec->SetCkovSig2(rms2);
 504     pRec->SetNClu(nClAcc);
 505 */
 506 //    Printf("FunMinPhot: reconstructed theta Cerenkov %f with %d photons",meanCkov,nClAcc);
 507     pRecHTA->SetCkovFit(meanCkov);
 508     pRecHTA->SetCkovSig2(rms*rms);
 509     pRecHTA->SetNClu(nClAcc);
 510   }
 511 }//FunMinPhot()
 512 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 513 void AliHMPIDReconHTA::InitDatabase()
 514 {
 515 // Construction a database of ring shapes on fly
 516 //   Arguments: none
 517 //   Returns  : none
 518 //  N.B. fgDatabase points to a TH2I with x-min dist from MIP
 519 //                                        y-dist from the ring of the MIP perpendicular to major axis
 520 //        The content is the packed info of track theta and thetaC in degrees
 521 //                        thetaC+1000*thTrk
 522 //
 523 //  TFile *pout = new TFile("./database.root","recreate");
 524
 525   TStopwatch timer;
 526   timer.Start();
 527
 528   AliInfo(Form("database HTA is being built.Please, wait..."));
 529 //
 530   Double_t x[3]={0,0,0},y[3];
 531
 532   AliHMPIDRecon rec;
 533
 534   if(!fParam) fParam=AliHMPIDParam::Instance();
 535   Double_t thetaMax = TMath::ACos(1./fParam->MeanIdxRad());
 536   Double_t thTrkMax = 1./TMath::ASin(fParam->MeanIdxRad());
 537
 538   Int_t nstepx = 1000;
 539   Int_t nstepy = 1000;
 540
 541 //  TH2F *fgDatabase = new TH2F("deconv","database;d1;d2;thC+1000*thTrk",500,0,50,150,0,15);
 542   //
 543   Double_t xrad = 0;
 544   Double_t yrad = 0;
 545   Double_t phTrk = 0;
 546
 547   for(Int_t i=0;i<nstepx;i++) {     //loop on thetaC
 548     for(Int_t j=0;j<nstepy;j++) {   //loop on theta particle
 549       Double_t thetaC = thetaMax/nstepx*((Double_t)i+0.5);
 550       Double_t thTrk  = thTrkMax/nstepy*((Double_t)j+0.5);
 551       //
 552       //mip position
 553       //
 554       Double_t sizeCh = 0.5*fParam->RadThick()+fParam->WinThick()+fParam->GapThick();
 555       Double_t xmip = xrad + sizeCh*TMath::Tan(thTrk)*TMath::Cos(phTrk);
 556       Double_t ymip = yrad + sizeCh*TMath::Tan(thTrk)*TMath::Sin(phTrk);
 557
 558       Double_t dist1,dist2;
 559       //
 560       //first point at phi=0
 561       //
 562       rec.SetTrack(xrad,yrad,thTrk,phTrk);
 563       TVector2 pos;
 564       pos=rec.TracePhot(thetaC,0);
 565
 566       if(pos.X()==-999) {
 567         dist1 = 0;            //open ring...anly the distance btw mip and point at 180 will be considered
 568       } else {
 569         x[0] = pos.X(); y[0] = pos.Y();
 570         dist1   = TMath::Sqrt((x[0]-xmip)*(x[0]-xmip)+(y[0]-ymip)*(y[0]-ymip));
 571       }
 572       //
 573       //second point at phi=180
 574       //
 575       rec.SetTrack(xrad,yrad,thTrk,phTrk);
 576       pos=rec.TracePhot(thetaC,TMath::Pi());
 577
 578       if(pos.X()==-999) {Printf("it should not happens!Bye");return;}
 579       x[1] = pos.X(); y[1] = pos.Y();
 580       if((x[1]-xmip)*(x[0]-xmip)>0) continue; // to avoid circles out mips (for very low ThetaC)
 581       dist2   = TMath::Sqrt((x[1]-xmip)*(x[1]-xmip)+(y[1]-ymip)*(y[1]-ymip));
 582
 583 //      Double_t distA = dist1+dist2;
 584       Double_t distA = dist2;     // only the minimum: problem of acceptance
 585       //
 586       //second point at phi=90
 587       //
 588       rec.SetTrack(xrad,yrad,thTrk,phTrk);
 589       pos=rec.TracePhot(thetaC,TMath::PiOver2());
 590
 591       if(pos.X()==-999) continue;
 592       x[2] = pos.X(); y[2] = pos.Y();
 593       Double_t distB   = TMath::Sqrt((x[2]-xmip)*(x[2]-xmip)+(y[2]-ymip)*(y[2]-ymip));
 594 // compact the infos...
 595       Int_t compact = (Int_t)(thetaC*TMath::RadToDeg())+1000*(Int_t)(thTrk*TMath::RadToDeg());
 596       Int_t bin = fgDatabase->FindBin(distA,distB);
 597       if(fgDatabase->GetBinContent(bin)==0) fgDatabase->Fill(distA,distB,compact);
 598     }
 599   }
 600
 601   FillZeroChan();
 602 //  fgDatabase = deconv;
 603
 604   timer.Stop();
 605   Double_t nSecs = timer.CpuTime();
 606   AliInfo(Form("database HTA successfully open in %3.1f sec.(CPU). Reconstruction is started.",nSecs));
 607
 608 //  pout->Write();
 609 //  pout->Close();
 610
 611 }
 612 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 613 void AliHMPIDReconHTA::FillZeroChan()const
 614 {
 615   //If fills eventually channel without entries
 616   //inthe histo "database" jyst interpolating the neighboring cells
 617   // Arguments: histogram pointer of the database
 618   //   Returns: none
 619   //
 620   Int_t nbinx = fgDatabase->GetNbinsX();
 621   Int_t nbiny = fgDatabase->GetNbinsY();
 622   for(Int_t i = 0;i<nbinx;i++) {
 623     for(Int_t j = 0;j<nbiny;j++) {
 624       if(fgDatabase->GetBinContent(i,j) == 0) {
 625         Int_t nXmin = i-1; Int_t nXmax=i+1;
 626         Int_t nYmin = j-1; Int_t nYmax=j+1;
 627         Int_t nc = 0;
 628         Double_t meanC =0;
 629         Double_t meanTrk =0;
 630         for(Int_t ix=nXmin;ix<=nXmax;ix++) {
 631           if(ix<0||ix>nbinx) continue;
 632           for(Int_t iy=nYmin;iy<=nYmax;iy++) {
 633             if(iy<0||iy>nbiny) continue;
 634             meanC  +=  (Int_t)fgDatabase->GetBinContent(ix,iy)%1000;
 635             meanTrk+=  (Int_t)fgDatabase->GetBinContent(ix,iy)/1000;
 636             nc++;
 637           }
 638           meanC/=nc; meanTrk/=nc;
 639           Int_t compact = (Int_t)meanC+1000*(Int_t)meanTrk;
 640           if(compact>0)fgDatabase->SetCellContent(i,j,compact);
 641         }
 642       }
 643     }
 644   }
 645 }
 646 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++