ITS/AliITStracking.cxx

   1 #include <iostream.h>
   2 #include <TMath.h>
   3 #include <TList.h>
   4 #include <TTree.h>
   5 #include <TVector.h>
   6 #include <TMatrix.h>
   7 #include <TObjectTable.h>
   8
   9 #include "AliITStracking.h"
  10 #include "AliRun.h"
  11 #include "AliITS.h"
  12 #include "AliITSgeom.h"
  13 #include "AliITSRecPoint.h"
  14 #include "AliITStrack.h"
  15
  16 ClassImp(AliITStracking)
  17
  18
  19 AliITStracking::AliITStracking(TList *trackITSlist, AliITStrack *reference,
  20                 AliITS *aliITS, TObjArray *rpoints, Double_t Ptref, Int_t **vettid, Bool_t flagvert,  AliITSRad *rl) {
  21 ///////////////////////   This function perform the tracking in ITS detectors /////////////////////
  22 ///////////////////////     reference is a pointer to the final best track    /////////////////////
  23 //Origin  A. Badala' and G.S. Pappalardo:  e-mail Angela.Badala@ct.infn.it, Giuseppe.S.Pappalardo@ct.infn.it
  24 // The authors  thank   Mariana Bondila to have help them to resolve some problems.  July-2000
  25
  26   Rlayer[0]=4.; Rlayer[1]=7.;  Rlayer[2]=14.9;  Rlayer[3]=23.8;  Rlayer[4]=39.1;  Rlayer[5]=43.6;
  27
  28   Int_t index;
  29   for(index =0; index<trackITSlist->GetSize(); index++) {
  30     AliITStrack *trackITS = (AliITStrack *) trackITSlist->At(index);
  31
  32     if((*trackITS).GetLayer()==7) reference->SetChi2(10.223e140);
  33    // cout <<" Layer inizio = "<<(*trackITS).GetLayer()<<"\n";
  34    //  cout<<"fvtrack =" <<"\n";
  35    //  cout << (*trackITS)(0) << " "<<(*trackITS)(1)<<" "<<(*trackITS)(2)<<" "<<(*trackITS)(3)<<" "<<(*trackITS)(4)<<"\n";
  36    //  cout<< " rtrack = "<<(*trackITS).Getrtrack()<<"\n";
  37    //  cout<< " Pt = "<<(*trackITS).GetPt()<<"\n";
  38    //  getchar();
  39     Double_t Chi2Now, Chi2Ref;
  40     if((*trackITS).GetLayer()==1 ) {
  41       Chi2Now = trackITS->GetChi2();
  42       Float_t NumClustNow = trackITS->GetNumClust();
  43       if(trackITS->GetNumClust()) Chi2Now /= (Double_t )trackITS->GetNumClust();
  44       Chi2Ref = reference->GetChi2();
  45       Float_t NumClustRef = reference->GetNumClust();
  46       if(reference->GetNumClust()) Chi2Ref /= (Double_t )reference->GetNumClust();
  47       //cout<<" Chi2Now and Chi2Ref = "<<Chi2Now<<" "<<Chi2Ref<<"\n";
  48                 if( NumClustNow > NumClustRef ) {*reference = *trackITS;}
  49       if((NumClustNow == NumClustRef )&& (Chi2Now < Chi2Ref))  {*reference = *trackITS;}
  50       continue;
  51     }
  52     Float_t NumClustNow = trackITS->GetNumClust();
  53     if(NumClustNow) {
  54       Chi2Now = trackITS->GetChi2();
  55       Chi2Now/=NumClustNow;
  56       //cout<<" Chi2Now =  "<<Chi2Now<<"\n";
  57     /*
  58     // if(Ptref > 0.6 && Chi2Now > 20.) continue;
  59     if(Ptref > 0.6 && Chi2Now > 30.) continue;
  60     if((Ptref <= 0.6 && Ptref>0.2)&& Chi2Now > 15.) continue;
  61      // if(Chi2Now>5.) continue;
  62       //if(Chi2Now>15.) continue;
  63      // if(Ptref <= 0.2 && Chi2Now > 10.) continue;
  64      if(Ptref <= 0.2 && Chi2Now > 8.) continue;
  65      */
  66      if(Ptref > 1.0 && Chi2Now > 30.) continue;
  67      if((Ptref >= 0.6 && Ptref<=1.0) && Chi2Now > 40.) continue;
  68      if((Ptref <= 0.6 && Ptref>0.2)&& Chi2Now > 40.) continue;
  69      if(Ptref <= 0.2 && Chi2Now > 8.) continue;
  70     }
  71
  72     Int_t layerInit = (*trackITS).GetLayer();
  73     Int_t layernew = layerInit - 2;  // -1 for new layer, -1 for matrix index
  74
  75     Int_t NLadder[]= {20, 40, 14, 22, 34, 38};
  76     Int_t NDetector[]= {4,  4,   6,  8, 23, 26};
  77
  78     TList listoftrack;
  79     Int_t ladp, ladm, detp,detm,ladinters,detinters;
  80     Int_t layerfin=layerInit-1;
  81     Double_t Rfin=Rlayer[layerfin-1];
  82     // cout<<"Prima di intersection \n";
  83
  84     Int_t  outinters=NewIntersection(*trackITS, Rfin, layerfin, ladinters, detinters);
  85
  86    // cout<<" outinters = "<<outinters<<"\n";
  87    //  cout<<" Layer ladder detector intersection ="<<layerfin<<" "<<ladinters<<" "<<detinters<<"\n";
  88    //  cout << " phiinters zinters = "<<(*trackITS)(0) << " "<<(*trackITS)(1)<<"\n"; getchar();
  89
  90     if(outinters==-1) continue;
  91
  92     Int_t flaghit=0;
  93     if(outinters==0){
  94       TVector Touclad(9), Toucdet(9);
  95       Int_t lycur=layerfin;
  96       ladp=ladinters+1;
  97       ladm=ladinters-1;
  98       if(ladm <= 0) ladm=NLadder[layerfin-1];
  99       if(ladp > NLadder[layerfin-1]) ladp=1;
 100       detp=detinters+1;
 101       detm=detinters-1;
 102       Int_t idetot=1;
 103       Touclad(0)=ladinters; Touclad(1)=ladm; Touclad(2)=ladp;
 104       Touclad(3)=ladinters; Touclad(4)=ladm; Touclad(5)=ladp;
 105       Touclad(6)=ladinters; Touclad(7)=ladm; Touclad(8)=ladp;
 106       Toucdet(0)=detinters; Toucdet(1)=detinters; Toucdet(2)=detinters;
 107       if(detm > 0 && detp <= NDetector[layerfin-1]) {
 108         idetot=9;
 109         Toucdet(3)=detm; Toucdet(4)=detm; Toucdet(5)=detm;
 110         Toucdet(6)=detp; Toucdet(7)=detp; Toucdet(8)=detp;
 111       }
 112
 113       if(detm > 0 && detp > NDetector[layerfin-1]) {
 114         idetot=6;
 115         Toucdet(3)=detm; Toucdet(4)=detm; Toucdet(5)=detm;
 116       }
 117
 118       if(detm <= 0 && detp <= NDetector[layerfin-1]) {
 119         idetot=6;
 120         Toucdet(3)=detp; Toucdet(4)=detp; Toucdet(5)=detp;
 121       }
 122       Int_t iriv;
 123       for (iriv=0; iriv<idetot; iriv++) {  //for on detectors
 124         AliITSgeom *g1 = aliITS->GetITSgeom();
 125         TVector CTF(9);
 126         g1->GetCenterThetaPhi(layerInit-1,(Int_t)Touclad(iriv),(Int_t)Toucdet(iriv),CTF);
 127
 128         // cout<<" layer, ladder, det, xo, yo, zo = "<<layerInit-1<<" "<<(Int_t)Touclad(iriv)<<
 129         // " "<<(Int_t)Toucdet(iriv)<<" "<<CTF(0)<<" "<<CTF(1)<<" "<<CTF(2)<< " "<<CTF(6)<<"\n"; getchar();
 130
 131         ////////////////////////////////////////////////////////////////////////////////////////////////
 132
 133         /*** Rec points sorted by module *****/
 134         /**************************************/
 135
 136         Int_t index;
 137         AliITSRecPoint *recp;
 138         AliITSgeom *geom = aliITS->GetITSgeom();
 139         index = geom->GetModuleIndex(lycur,Touclad(iriv),Toucdet(iriv));
 140         Int_t lay,lad,det;
 141         geom->GetModuleId(index,lay,lad,det);
 142         aliITS->ResetRecPoints();
 143         //gAlice->TreeR()->GetEvent(index+1); //first entry in TreeR is empty
 144         gAlice->TreeR()->GetEvent(index); //first entry in TreeR is empty
 145
 146         Int_t npoints=rpoints->GetEntries();
 147         Int_t *indlist=new Int_t[npoints+1];
 148         Int_t counter=0;
 149         Int_t ind;
 150         for (ind=0; ind<=npoints; ind++) {
 151           indlist[ind]=-1;
 152                if (*(vettid[index]+ind)==0) {
 153               indlist[counter]=ind;
 154                    counter++;
 155               }
 156         }
 157
 158         ind=-1;
 159
 160         for(;;) {
 161           ind++;
 162           if(indlist[ind] < 0) recp=0;
 163                else recp = (AliITSRecPoint*)rpoints->UncheckedAt(indlist[ind]);
 164
 165           if((!recp)  )  break;
 166           TVector cluster(3),vecclust(9);
 167           vecclust(6)=vecclust(7)=vecclust(8)=-1.;
 168           Double_t sigma[2];
 169             //modificata 8-3-2001
 170           // set veclust in global
 171           Float_t global[3], local[3];
 172           local[0]=recp->GetX();
 173           local[1]=0.;
 174           local[2]= recp->GetZ();
 175           AliITSgeom *g1 = aliITS->GetITSgeom();
 176           Int_t play = lycur;
 177           Int_t plad = TMath::Nint(Touclad(iriv));
 178           Int_t pdet = TMath::Nint(Toucdet(iriv));
 179           g1->LtoG(play,plad,pdet,local,global);
 180
 181           vecclust(0)=global[0];
 182           vecclust(1)=global[1];
 183           vecclust(2)=global[2];
 184
 185           /*
 186           ////  modificato 8-3-2001
 187           vecclust(0)=recp->GetRhit();;
 188           vecclust(1)=recp->Getphi();
 189           vecclust(2)=recp->GetZglobal();
 190           */
 191
 192           vecclust(3) = (float)recp->fTracks[0];
 193           vecclust(4) = (float)indlist[ind];
 194           vecclust(5) = (float)index;
 195           vecclust(6) = (float)recp->fTracks[0];
 196           vecclust(7) = (float)recp->fTracks[1];
 197           vecclust(8) = (float)recp->fTracks[2];
 198
 199           sigma[0] = (Double_t)  recp->GetSigmaX2();
 200           sigma[1] = (Double_t) recp->GetSigmaZ2();
 201            //commentato 8-3-2001
 202          //now we are in r,phi,z in global
 203           cluster(0) = TMath::Sqrt(vecclust(0)*vecclust(0)+vecclust(1)*vecclust(1));//r hit
 204           cluster(1) = PhiDef(vecclust(0),vecclust(1));    // phi hit
 205           cluster(2) = vecclust(2);                   // z hit
 206
 207           /*
 208          //modificato 8-3-2001
 209           cluster(0) = vecclust(0);//r hit
 210           cluster(1) = vecclust(1);    // phi hit
 211           cluster(2) = vecclust(2);                   // z hit
 212           */
 213          // cout<<" layer = "<<play<<"\n";
 214          // cout<<" cluster prima = "<<vecclust(0)<<" "<<vecclust(1)<<" "
 215          // <<vecclust(2)<<"\n"; getchar();
 216           //cluster(1)= cluster(1)-trackITS->Getalphaprov();  //provvisorio;
 217                          //if(cluster(1)<0.) cluster(1)+=2.*TMath::Pi(); //provvisorio
 218                          //cout<<" cluster(1) dopo = "<<cluster(1)<< " alphaprov = "<<trackITS->Getalphaprov()<<"\n";
 219           Float_t sigmatotphi, sigmatotz;
 220
 221           //Float_t epsphi=3.2, epsz=3.;
 222             Float_t epsphi=5.0, epsz=5.0;
 223           if(Ptref<0.2) {epsphi=3.; epsz=3.;}
 224
 225           Double_t Rtrack=(*trackITS).Getrtrack();
 226           Double_t sigmaphi=sigma[0]/(Rtrack*Rtrack);
 227           sigmatotphi=epsphi*TMath::Sqrt(sigmaphi + (*trackITS).GetSigmaphi());
 228
 229           sigmatotz=epsz*TMath::Sqrt(sigma[1] + (*trackITS).GetSigmaZ());
 230   //cout<<"cluster e sigmatotphi e track = "<<cluster(0)<<" "<<cluster(1)<<" "<<sigmatotphi<<" "<<vecclust(3)<<"\n";
 231   //if(vecclust(3)==481) getchar();
 232                if(cluster(1)<6. && (*trackITS).Getphi()>6.) cluster(1)=cluster(1)+(2.*TMath::Pi());
 233                if(cluster(1)>6. && (*trackITS).Getphi()<6.) cluster(1)=cluster(1)-(2.*TMath::Pi());
 234           if(TMath::Abs(cluster(1)-(*trackITS).Getphi()) > sigmatotphi) continue;
 235                         // cout<<" supero sigmaphi \n";
 236           AliITStrack *newTrack = new AliITStrack((*trackITS));
 237           (*newTrack).SetLayer((*trackITS).GetLayer()-1);
 238
 239                if (TMath::Abs(Rtrack-cluster(0))/Rtrack>1e-6)
 240                                                (*newTrack).Correct(Double_t(cluster(0)));
 241                         //cout<<" cluster(2) e (*newTrack).GetZ() = "<<cluster(2)<<" "<<        (*newTrack).GetZ()<<"\n";
 242           if(TMath::Abs(cluster(2)-(*newTrack).GetZ()) > sigmatotz){
 243              delete newTrack;
 244              continue;}
 245
 246           if(iriv == 0) flaghit=1;
 247
 248           (*newTrack).AddMS(rl);  // add the multiple scattering matrix to the covariance matrix
 249           (*newTrack).AddEL(rl,1.,0);
 250
 251           Double_t sigmanew[2];
 252           sigmanew[0]= sigmaphi;
 253           sigmanew[1]=sigma[1];
 254
 255           if(flagvert)
 256             KalmanFilterVert(newTrack,cluster,sigmanew);
 257           else
 258             KalmanFilter(newTrack,cluster,sigmanew);
 259
 260
 261           (*newTrack).PutCluster(layernew, vecclust);
 262            newTrack->AddClustInTrack();
 263
 264            listoftrack.AddLast(newTrack);
 265
 266         }   // end of for(;;) on rec points
 267
 268         delete [] indlist;
 269
 270       }  // end of for on detectors
 271
 272     }//end if(outinters==0)
 273
 274     if(flaghit==0 || outinters==-2) {
 275       AliITStrack *newTrack = new AliITStrack(*trackITS);
 276       (*newTrack).SetLayer((*trackITS).GetLayer()-1);
 277       (*newTrack).AddMS(rl);  // add the multiple scattering matrix to the covariance matrix
 278       (*newTrack).AddEL(rl,1.,0);
 279
 280       listoftrack.AddLast(newTrack);
 281     }
 282
 283
 284     //gObjectTable->Print();   // stampa memoria
 285
 286     AliITStracking(&listoftrack, reference, aliITS, rpoints,Ptref,vettid,flagvert,rl);
 287     listoftrack.Delete();
 288   } // end of for on tracks
 289
 290   //gObjectTable->Print();   // stampa memoria
 291
 292 }
 293
 294
 295 Int_t AliITStracking::NewIntersection(AliITStrack &track, Double_t rk,Int_t layer, Int_t &ladder, Int_t &detector) {
 296 //Origin  A. Badala' and G.S. Pappalardo:  e-mail Angela.Badala@ct.infn.it, Giuseppe.S.Pappalardo@ct.infn.it
 297 // Found the intersection and the detector
 298
 299   if(track.DoNotCross(rk)){ /*cout<< " Do not cross \n";*/ return -1;}
 300   track.Propagation(rk);
 301   Double_t zinters=track.GetZ();
 302   Double_t phinters=track.Getphi();
 303   //phinters = phinters+track.Getalphaprov(); //provvisorio
 304   //if(phinters>2.*3.14) phinters=phinters-2.*3.14; //provvisorio
 305   //cout<<"zinters = "<<zinters<<"  phinters = "<<phinters<<"\n";
 306
 307   //////////////////////////////////      limits for Geometry 5      /////////////////////////////
 308
 309   Int_t NLadder[]= {20, 40, 14, 22, 34, 38};
 310   Int_t NDetector[]= {4,  4,   6,  8, 23, 26};
 311
 312   Float_t Detx[]= {0.64, 0.64, 3.509, 3.509, 3.65, 3.65 };
 313   Float_t Detz[]= {4.19, 4.19, 3.75 , 3.75 , 2   , 2    };
 314   ////////////////////////////////////////////////////////////////////////////////////////////////
 315
 316   TVector det(9);
 317   TVector ListDet(2);
 318   TVector DistZCenter(2);
 319   AliITSgeom *g1 = ((AliITS*)gAlice->GetDetector("ITS"))->GetITSgeom();
 320   Int_t iz=0;
 321   Double_t epsz=1.2;
 322   Double_t epszpixel=0.05;
 323
 324   Int_t iD;
 325   for(iD = 1; iD<= NDetector[layer-1]; iD++) {
 326     g1->GetCenterThetaPhi(layer,1,iD,det);
 327     Double_t zmin=det(2)-Detz[layer-1];
 328     if(iD==1) zmin=det(2)-(Detz[layer-1])*epsz;
 329     Double_t zmax=det(2)+Detz[layer-1];
 330     if(iD==NDetector[layer-1]) zmax=det(2)+(Detz[layer-1])*epsz;
 331     //added to take into account problem on drift
 332     if(layer == 4 || layer==3) zmin=zmin-epszpixel; zmax=zmax+epszpixel;
 333     //cout<<"zmin zinters zmax det(2)= "<<zmin<<" "<<zinters<<" "<<zmax<<" "<<det(2)<<"\n";
 334     if(zinters > zmin && zinters <= zmax) {
 335       if(iz>1) {cout<< " Errore su iz in NewIntersection \n"; getchar();}
 336       else {
 337         ListDet(iz)= iD; DistZCenter(iz)=TMath::Abs(zinters-det(2)); iz++;
 338       }
 339     }
 340   }
 341
 342   if(iz==0) {/* cout<< " No detector along Z \n";*/ return -2;}
 343   detector=Int_t (ListDet(0));
 344   if(iz>1 && (DistZCenter(0)>DistZCenter(1)))   detector=Int_t (ListDet(1));
 345
 346   AliITSgeom *g2 = ((AliITS*)gAlice->GetDetector("ITS"))->GetITSgeom();
 347   Float_t global[3];
 348   Float_t local[3];
 349   TVector ListLad(2);
 350   TVector DistphiCenter(2);
 351   Int_t ip=0;
 352   Double_t pigre=TMath::Pi();
 353
 354   Int_t iLd;
 355   for(iLd = 1; iLd<= NLadder[layer-1]; iLd++) {
 356           g1->GetCenterThetaPhi(layer,iLd,detector,det);
 357   Double_t phidet=PhiDef(Double_t(det(0)),Double_t(det(1)));
 358   // cout<<" layer phidet e det(6) = "<< layer<<" "<<phidet<<" "<<det(6)<<"\n"; getchar();
 359   Double_t xmin,ymin,xmax,ymax;
 360  // Double_t phiconfr=0.0;
 361   //cout<<" phiconfr inizio =  "<<phiconfr <<"\n"; getchar();
 362   local[1]=local[2]=0.;
 363   local[0]= -(Detx[layer-1]);
 364   if(layer==1)    local[0]= (Detx[layer-1]);  //take into account different reference system
 365   g2->LtoG(layer,iLd,detector,local,global);
 366   xmax=global[0]; ymax=global[1];
 367   local[0]= (Detx[layer-1]);
 368   if(layer==1)    local[0]= -(Detx[layer-1]);  //take into account different reference system
 369   g2->LtoG(layer,iLd,detector,local,global);
 370   xmin=global[0]; ymin=global[1];
 371   Double_t phimin=PhiDef(xmin,ymin);
 372   Double_t phimax=PhiDef(xmax,ymax);
 373   //cout<<" xmin ymin = "<<xmin<<" "<<ymin<<"\n";
 374   // cout<<" xmax ymax = "<<xmax<<" "<<ymax<<"\n";
 375   // cout<<" iLd phimin phimax ="<<iLd<<" "<<phimin<<" "<<phimax<<"\n";
 376
 377   Double_t phiconfr=phinters;
 378  if(phimin>phimax ){
 379      if(phimin <5.5) {cout<<" Error in NewIntersection for phi \n"; getchar();}
 380     phimin=phimin-(2.*pigre);
 381     if(phinters>(1.5*pigre)) phiconfr=phinters-(2.*pigre);
 382     if(phidet>(1.5*pigre)) phidet=phidet-(2.*pigre);
 383   }
 384   //  cout<<" phiconfr finale = "<<phiconfr<<"\n"; getchar();
 385   if(phiconfr>phimin && phiconfr<= phimax) {
 386     if(ip>1) {
 387       cout<< " Errore su ip in NewIntersection \n"; getchar();
 388     }
 389       else  {
 390         ListLad(ip)= iLd; DistphiCenter(ip)=TMath::Abs(phiconfr-phidet); ip++;
 391       }
 392     }
 393   }
 394   if(ip==0) { cout<< " No detector along phi \n"; getchar();}
 395   ladder=Int_t (ListLad(0));
 396   if(ip>1 && (DistphiCenter(0)>DistphiCenter(1)))   ladder=Int_t (ListLad(1));
 397
 398   return 0;
 399 }
 400
 401
 402 Double_t AliITStracking::PhiDef(Double_t x, Double_t y){
 403   Double_t pigre= TMath::Pi();
 404   Double_t phi=0.0;
 405   if(y == 0. || x == 0.) {
 406     if(y == 0. && x == 0.) {
 407       cout << "  Error in AliITStracking::PhiDef x=0 and y=0 \n"; getchar();
 408     }
 409     if(y==0. && x>0.) phi=0.;
 410     if(y==0. && x<0.) phi=pigre;
 411     if(x==0 && y>0.) phi=pigre/2.;
 412     if(x==0 && y<0.) phi=1.5*pigre;
 413   }
 414     else {
 415       if (x>0. && y>0.) phi=TMath::ATan(y/x);
 416       if (x<0. && y>0.) phi=pigre+TMath::ATan(y/x);
 417       if (x<0. && y<0.) phi=pigre+TMath::ATan(y/x);
 418       if (x>0. && y<0.) phi=(2.*pigre)+TMath::ATan(y/x);
 419     }
 420   if(phi<0. || phi>(2*pigre)) {
 421     cout<<" Error on phi in  AliITStracking::PhiDef \n"; getchar();
 422   }
 423   return phi;
 424 }
 425
 426
 427 void AliITStracking::KalmanFilter(AliITStrack *newTrack,TVector &cluster,Double_t sigma[2]){
 428 //Origin  A. Badala' and G.S. Pappalardo:  e-mail Angela.Badala@ct.infn.it, Giuseppe.S.Pappalardo@ct.infn.it
 429 // Kalman filter without vertex constraint
 430
 431
 432   ////////////////////////////// Evaluation of the measurement vector /////////////////////////////////////
 433
 434   Double_t m[2];
 435   Double_t rk,phik,zk;
 436   rk=cluster(0);   phik=cluster(1);  zk=cluster(2);
 437   m[0]=phik;    m[1]=zk;
 438
 439   ///////////////////////////////////// Evaluation of the error matrix V  ///////////////////////////////
 440
 441   Double_t V00=sigma[0];
 442   Double_t V11=sigma[1];
 443
 444   ///////////////////////////////////////////////////////////////////////////////////////////
 445
 446
 447   Double_t Cin00,Cin10,Cin20,Cin30,Cin40,Cin11,Cin21,Cin31,Cin41,Cin22,Cin32,Cin42,Cin33,Cin43,Cin44;
 448
 449   newTrack->GetCElements(Cin00,Cin10,Cin11,Cin20,Cin21,Cin22,Cin30,Cin31,Cin32,Cin33,Cin40,
 450                          Cin41,Cin42,Cin43,Cin44); //get C matrix
 451
 452   Double_t Rold00=Cin00+V00;
 453   Double_t Rold10=Cin10;
 454   Double_t Rold11=Cin11+V11;
 455
 456 //////////////////////////////////// R matrix inversion  ///////////////////////////////////////////////
 457
 458   Double_t det=Rold00*Rold11-Rold10*Rold10;
 459   Double_t R00=Rold11/det;
 460   Double_t R10=-Rold10/det;
 461   Double_t R11=Rold00/det;
 462
 463 ////////////////////////////////////////////////////////////////////////////////////////////////////////
 464
 465   Double_t K00=Cin00*R00+Cin10*R10;
 466   Double_t K01=Cin00*R10+Cin10*R11;
 467   Double_t K10=Cin10*R00+Cin11*R10;
 468   Double_t K11=Cin10*R10+Cin11*R11;
 469   Double_t K20=Cin20*R00+Cin21*R10;
 470   Double_t K21=Cin20*R10+Cin21*R11;
 471   Double_t K30=Cin30*R00+Cin31*R10;
 472   Double_t K31=Cin30*R10+Cin31*R11;
 473   Double_t K40=Cin40*R00+Cin41*R10;
 474   Double_t K41=Cin40*R10+Cin41*R11;
 475
 476   Double_t X0,X1,X2,X3,X4;
 477   newTrack->GetXElements(X0,X1,X2,X3,X4);     // get the state vector
 478
 479   Double_t savex0=X0, savex1=X1;
 480
 481   X0+=K00*(m[0]-savex0)+K01*(m[1]-savex1);
 482   X1+=K10*(m[0]-savex0)+K11*(m[1]-savex1);
 483   X2+=K20*(m[0]-savex0)+K21*(m[1]-savex1);
 484   X3+=K30*(m[0]-savex0)+K31*(m[1]-savex1);
 485   X4+=K40*(m[0]-savex0)+K41*(m[1]-savex1);
 486
 487   Double_t C00,C10,C20,C30,C40,C11,C21,C31,C41,C22,C32,C42,C33,C43,C44;
 488
 489   C00=Cin00-K00*Cin00-K01*Cin10;
 490   C10=Cin10-K00*Cin10-K01*Cin11;
 491   C20=Cin20-K00*Cin20-K01*Cin21;
 492   C30=Cin30-K00*Cin30-K01*Cin31;
 493   C40=Cin40-K00*Cin40-K01*Cin41;
 494
 495   C11=Cin11-K10*Cin10-K11*Cin11;
 496   C21=Cin21-K10*Cin20-K11*Cin21;
 497   C31=Cin31-K10*Cin30-K11*Cin31;
 498   C41=Cin41-K10*Cin40-K11*Cin41;
 499
 500   C22=Cin22-K20*Cin20-K21*Cin21;
 501   C32=Cin32-K20*Cin30-K21*Cin31;
 502   C42=Cin42-K20*Cin40-K21*Cin41;
 503
 504   C33=Cin33-K30*Cin30-K31*Cin31;
 505   C43=Cin43-K30*Cin40-K31*Cin41;
 506
 507   C44=Cin44-K40*Cin40-K41*Cin41;
 508
 509   newTrack->PutXElements(X0,X1,X2,X3,X4);               // put the new state vector
 510
 511   newTrack->PutCElements(C00,C10,C11,C20,C21,C22,C30,C31,C32,C33,C40,C41,C42,C43,C44); // put in track the
 512                                                                                        // new cov matrix
 513   Double_t VMCold00=V00-C00;
 514   Double_t VMCold10=-C10;
 515   Double_t VMCold11=V11-C11;
 516
 517 ///////////////////////////////////// Matrix VMC inversion  ////////////////////////////////////////////////
 518
 519   det=VMCold00*VMCold11-VMCold10*VMCold10;
 520   Double_t VMC00=VMCold11/det;
 521   Double_t VMC10=-VMCold10/det;
 522   Double_t VMC11=VMCold00/det;
 523
 524 ////////////////////////////////////////////////////////////////////////////////////////////////////////////
 525
 526   Double_t chi2=(m[0]-X0)*( VMC00*(m[0]-X0) + 2.*VMC10*(m[1]-X1) ) +
 527                 (m[1]-X1)*VMC11*(m[1]-X1);
 528
 529   newTrack->SetChi2(newTrack->GetChi2()+chi2);
 530
 531 }
 532
 533
 534 void AliITStracking::KalmanFilterVert(AliITStrack *newTrack,TVector &cluster,Double_t sigma[2]){
 535 //Origin  A. Badala' and G.S. Pappalardo:  e-mail Angela.Badala@ct.infn.it, Giuseppe.S.Pappalardo@ct.infn.it
 536 // Kalman filter with vertex constraint
 537
 538   ////////////////////////////// Evaluation of the measurement vector m ///////////////
 539
 540   Double_t m[4];
 541   Double_t rk,phik,zk;
 542   rk=cluster(0);   phik=cluster(1);  zk=cluster(2);
 543   m[0]=phik;    m[1]=zk;
 544
 545   Double_t CC=(*newTrack).GetC();
 546   Double_t Zv=(*newTrack).GetZv();
 547   Double_t Dv=(*newTrack).GetDv();
 548   Double_t Cy=CC/2.;
 549   Double_t tgl= (zk-Zv)*Cy/TMath::ASin(Cy*rk);
 550   m[2]=Dv;    m[3]=tgl;
 551
 552   ///////////////////////////////////// Evaluation of the error matrix V  //////////////
 553   Int_t Layer=newTrack->GetLayer();
 554   Double_t V00=sigma[0];
 555   Double_t V11=sigma[1];
 556   Double_t V31=sigma[1]/rk;
 557   Double_t sigmaDv=newTrack->GetsigmaDv();
 558   Double_t V22=sigmaDv*sigmaDv  + newTrack->Getd2(Layer-1);
 559   Double_t V32=newTrack->Getdtgl(Layer-1);
 560   Double_t sigmaZv=newTrack->GetsigmaZv();
 561   Double_t V33=(sigma[1]+sigmaZv*sigmaZv)/(rk*rk) + newTrack->Gettgl2(Layer-1);
 562   ///////////////////////////////////////////////////////////////////////////////////////
 563
 564   Double_t Cin00,Cin10,Cin11,Cin20,Cin21,Cin22,Cin30,Cin31,Cin32,Cin33,Cin40,Cin41,Cin42,Cin43,Cin44;
 565
 566   newTrack->GetCElements(Cin00,Cin10,Cin11,Cin20,Cin21,Cin22,Cin30,Cin31,Cin32,Cin33,Cin40,
 567                          Cin41,Cin42,Cin43,Cin44); //get C matrix
 568
 569   Double_t R[4][4];
 570   R[0][0]=Cin00+V00;
 571   R[1][0]=Cin10;
 572   R[2][0]=Cin20;
 573   R[3][0]=Cin30;
 574   R[1][1]=Cin11+V11;
 575   R[2][1]=Cin21;
 576   R[3][1]=Cin31+sigma[1]/rk;
 577   R[2][2]=Cin22+sigmaDv*sigmaDv+newTrack->Getd2(Layer-1);
 578   R[3][2]=Cin32+newTrack->Getdtgl(Layer-1);
 579   R[3][3]=Cin33+(sigma[1]+sigmaZv*sigmaZv)/(rk*rk) + newTrack->Gettgl2(Layer-1);
 580
 581   R[0][1]=R[1][0]; R[0][2]=R[2][0]; R[0][3]=R[3][0]; R[1][2]=R[2][1]; R[1][3]=R[3][1];
 582   R[2][3]=R[3][2];
 583
 584 /////////////////////  Matrix R inversion ////////////////////////////////////////////
 585
 586   const Int_t n=4;
 587   Double_t big, hold;
 588   Double_t d=1.;
 589   Int_t ll[n],mm[n];
 590
 591   Int_t i,j,k;
 592
 593   for(k=0; k<n; k++) {
 594     ll[k]=k;
 595     mm[k]=k;
 596     big=R[k][k];
 597     for(j=k; j<n ; j++) {
 598       for (i=j; i<n; i++) {
 599         if(TMath::Abs(big) < TMath::Abs(R[i][j]) ) { big=R[i][j]; ll[k]=i; mm[k]=j; }
 600       }
 601     }
 602 //
 603     j= ll[k];
 604     if(j > k) {
 605       for(i=0; i<n; i++) { hold=-R[k][i]; R[k][i]=R[j][i]; R[j][i]=hold; }
 606
 607     }
 608 //
 609     i=mm[k];
 610     if(i > k ) {
 611       for(j=0; j<n; j++) { hold=-R[j][k]; R[j][k]=R[j][i]; R[j][i]=hold; }
 612     }
 613 //
 614     if(!big) {
 615       d=0.;
 616       cout << "Singular matrix\n";
 617     }
 618     for(i=0; i<n; i++) {
 619       if(i == k) { continue; }
 620       R[i][k]=R[i][k]/(-big);
 621     }
 622 //
 623     for(i=0; i<n; i++) {
 624       hold=R[i][k];
 625       for(j=0; j<n; j++) {
 626         if(i == k || j == k) { continue; }
 627         R[i][j]=hold*R[k][j]+R[i][j];
 628       }
 629     }
 630 //
 631     for(j=0; j<n; j++) {
 632       if(j == k) { continue; }
 633       R[k][j]=R[k][j]/big;
 634     }
 635 //
 636     d=d*big;
 637 //
 638     R[k][k]=1./big;
 639   }
 640 //
 641   for(k=n-1; k>=0; k--) {
 642     i=ll[k];
 643     if(i > k) {
 644       for (j=0; j<n; j++) {hold=R[j][k]; R[j][k]=-R[j][i]; R[j][i]=hold;}
 645     }
 646     j=mm[k];
 647     if(j > k) {
 648       for (i=0; i<n; i++) {hold=R[k][i]; R[k][i]=-R[j][i]; R[j][i]=hold;}
 649       }
 650   }
 651 //////////////////////////////////////////////////////////////////////////////////
 652
 653
 654   Double_t K00=Cin00*R[0][0]+Cin10*R[1][0]+Cin20*R[2][0]+Cin30*R[3][0];
 655   Double_t K01=Cin00*R[1][0]+Cin10*R[1][1]+Cin20*R[2][1]+Cin30*R[3][1];
 656   Double_t K02=Cin00*R[2][0]+Cin10*R[2][1]+Cin20*R[2][2]+Cin30*R[3][2];
 657   Double_t K03=Cin00*R[3][0]+Cin10*R[3][1]+Cin20*R[3][2]+Cin30*R[3][3];
 658   Double_t K10=Cin10*R[0][0]+Cin11*R[1][0]+Cin21*R[2][0]+Cin31*R[3][0];
 659   Double_t K11=Cin10*R[1][0]+Cin11*R[1][1]+Cin21*R[2][1]+Cin31*R[3][1];
 660   Double_t K12=Cin10*R[2][0]+Cin11*R[2][1]+Cin21*R[2][2]+Cin31*R[3][2];
 661   Double_t K13=Cin10*R[3][0]+Cin11*R[3][1]+Cin21*R[3][2]+Cin31*R[3][3];
 662   Double_t K20=Cin20*R[0][0]+Cin21*R[1][0]+Cin22*R[2][0]+Cin32*R[3][0];
 663   Double_t K21=Cin20*R[1][0]+Cin21*R[1][1]+Cin22*R[2][1]+Cin32*R[3][1];
 664   Double_t K22=Cin20*R[2][0]+Cin21*R[2][1]+Cin22*R[2][2]+Cin32*R[3][2];
 665   Double_t K23=Cin20*R[3][0]+Cin21*R[3][1]+Cin22*R[3][2]+Cin32*R[3][3];
 666   Double_t K30=Cin30*R[0][0]+Cin31*R[1][0]+Cin32*R[2][0]+Cin33*R[3][0];
 667   Double_t K31=Cin30*R[1][0]+Cin31*R[1][1]+Cin32*R[2][1]+Cin33*R[3][1];
 668   Double_t K32=Cin30*R[2][0]+Cin31*R[2][1]+Cin32*R[2][2]+Cin33*R[3][2];
 669   Double_t K33=Cin30*R[3][0]+Cin31*R[3][1]+Cin32*R[3][2]+Cin33*R[3][3];
 670   Double_t K40=Cin40*R[0][0]+Cin41*R[1][0]+Cin42*R[2][0]+Cin43*R[3][0];
 671   Double_t K41=Cin40*R[1][0]+Cin41*R[1][1]+Cin42*R[2][1]+Cin43*R[3][1];
 672   Double_t K42=Cin40*R[2][0]+Cin41*R[2][1]+Cin42*R[2][2]+Cin43*R[3][2];
 673   Double_t K43=Cin40*R[3][0]+Cin41*R[3][1]+Cin42*R[3][2]+Cin43*R[3][3];
 674
 675   Double_t X0,X1,X2,X3,X4;
 676   newTrack->GetXElements(X0,X1,X2,X3,X4);     // get the state vector
 677
 678   Double_t savex0=X0, savex1=X1, savex2=X2, savex3=X3;
 679
 680   X0+=K00*(m[0]-savex0)+K01*(m[1]-savex1)+K02*(m[2]-savex2)+
 681       K03*(m[3]-savex3);
 682   X1+=K10*(m[0]-savex0)+K11*(m[1]-savex1)+K12*(m[2]-savex2)+
 683       K13*(m[3]-savex3);
 684   X2+=K20*(m[0]-savex0)+K21*(m[1]-savex1)+K22*(m[2]-savex2)+
 685       K23*(m[3]-savex3);
 686   X3+=K30*(m[0]-savex0)+K31*(m[1]-savex1)+K32*(m[2]-savex2)+
 687       K33*(m[3]-savex3);
 688   X4+=K40*(m[0]-savex0)+K41*(m[1]-savex1)+K42*(m[2]-savex2)+
 689       K43*(m[3]-savex3);
 690
 691   Double_t C00,C10,C20,C30,C40,C11,C21,C31,C41,C22,C32,C42,C33,C43,C44;
 692
 693   C00=Cin00-K00*Cin00-K01*Cin10-K02*Cin20-K03*Cin30;
 694   C10=Cin10-K00*Cin10-K01*Cin11-K02*Cin21-K03*Cin31;
 695   C20=Cin20-K00*Cin20-K01*Cin21-K02*Cin22-K03*Cin32;
 696   C30=Cin30-K00*Cin30-K01*Cin31-K02*Cin32-K03*Cin33;
 697   C40=Cin40-K00*Cin40-K01*Cin41-K02*Cin42-K03*Cin43;
 698
 699   C11=Cin11-K10*Cin10-K11*Cin11-K12*Cin21-K13*Cin31;
 700   C21=Cin21-K10*Cin20-K11*Cin21-K12*Cin22-K13*Cin32;
 701   C31=Cin31-K10*Cin30-K11*Cin31-K12*Cin32-K13*Cin33;
 702   C41=Cin41-K10*Cin40-K11*Cin41-K12*Cin42-K13*Cin43;
 703
 704   C22=Cin22-K20*Cin20-K21*Cin21-K22*Cin22-K23*Cin32;
 705   C32=Cin32-K20*Cin30-K21*Cin31-K22*Cin32-K23*Cin33;
 706   C42=Cin42-K20*Cin40-K21*Cin41-K22*Cin42-K23*Cin43;
 707
 708   C33=Cin33-K30*Cin30-K31*Cin31-K32*Cin32-K33*Cin33;
 709   C43=Cin43-K30*Cin40-K31*Cin41-K32*Cin42-K33*Cin43;
 710
 711   C44=Cin44-K40*Cin40-K41*Cin41-K42*Cin42-K43*Cin43;
 712
 713   newTrack->PutXElements(X0,X1,X2,X3,X4);               // put the new state vector
 714
 715   newTrack->PutCElements(C00,C10,C11,C20,C21,C22,C30,C31,C32,C33,C40,C41,C42,C43,C44); // put in track the
 716                                                                                        // new cov matrix
 717
 718   Double_t VMC[4][4];
 719
 720   VMC[0][0]=V00-C00; VMC[1][0]=-C10; VMC[2][0]=-C20; VMC[3][0]=-C30;
 721   VMC[1][1]=V11-C11; VMC[2][1]=-C21; VMC[3][1]=V31-C31;
 722   VMC[2][2]=V22-C22; VMC[3][2]=V32-C32;
 723   VMC[3][3]=V33-C33;
 724
 725   VMC[0][1]=VMC[1][0]; VMC[0][2]=VMC[2][0]; VMC[0][3]=VMC[3][0];
 726   VMC[1][2]=VMC[2][1]; VMC[1][3]=VMC[3][1];
 727   VMC[2][3]=VMC[3][2];
 728
 729
 730 /////////////////////// VMC matrix inversion ///////////////////////////////////
 731
 732   d=1.;
 733
 734   for(k=0; k<n; k++) {
 735     ll[k]=k;
 736     mm[k]=k;
 737     big=VMC[k][k];
 738     for(j=k; j<n ; j++) {
 739       for (i=j; i<n; i++) {
 740         if(TMath::Abs(big) < TMath::Abs(VMC[i][j]) ) { big=VMC[i][j]; ll[k]=i; mm[k]=j; }
 741       }
 742     }
 743 //
 744     j= ll[k];
 745     if(j > k) {
 746       for(i=0; i<n; i++) { hold=-VMC[k][i]; VMC[k][i]=VMC[j][i]; VMC[j][i]=hold; }
 747
 748     }
 749 //
 750     i=mm[k];
 751     if(i > k ) {
 752       for(j=0; j<n; j++) { hold=-VMC[j][k]; VMC[j][k]=VMC[j][i]; VMC[j][i]=hold; }
 753     }
 754 //
 755     if(!big) {
 756       d=0.;
 757       cout << "Singular matrix\n";
 758     }
 759     for(i=0; i<n; i++) {
 760       if(i == k) { continue; }
 761       VMC[i][k]=VMC[i][k]/(-big);
 762     }
 763 //
 764     for(i=0; i<n; i++) {
 765       hold=VMC[i][k];
 766       for(j=0; j<n; j++) {
 767         if(i == k || j == k) { continue; }
 768         VMC[i][j]=hold*VMC[k][j]+VMC[i][j];
 769       }
 770     }
 771 //
 772     for(j=0; j<n; j++) {
 773       if(j == k) { continue; }
 774       VMC[k][j]=VMC[k][j]/big;
 775     }
 776 //
 777     d=d*big;
 778 //
 779     VMC[k][k]=1./big;
 780   }
 781 //
 782   for(k=n-1; k>=0; k--) {
 783     i=ll[k];
 784     if(i > k) {
 785       for (j=0; j<n; j++) {hold=VMC[j][k]; VMC[j][k]=-VMC[j][i]; VMC[j][i]=hold;}
 786     }
 787     j=mm[k];
 788     if(j > k) {
 789       for (i=0; i<n; i++) {hold=VMC[k][i]; VMC[k][i]=-VMC[j][i]; VMC[j][i]=hold;}
 790       }
 791   }
 792
 793
 794 ////////////////////////////////////////////////////////////////////////////////
 795
 796   Double_t chi2=(m[0]-X0)*( VMC[0][0]*(m[0]-X0) + 2.*VMC[1][0]*(m[1]-X1) +
 797                    2.*VMC[2][0]*(m[2]-X2)+ 2.*VMC[3][0]*(m[3]-X3) ) +
 798                 (m[1]-X1)* ( VMC[1][1]*(m[1]-X1) + 2.*VMC[2][1]*(m[2]-X2)+
 799                    2.*VMC[3][1]*(m[3]-X3) ) +
 800                 (m[2]-X2)* ( VMC[2][2]*(m[2]-X2)+ 2.*VMC[3][2]*(m[3]-X3) ) +
 801                 (m[3]-X3)*VMC[3][3]*(m[3]-X3);
 802
 803   newTrack->SetChi2(newTrack->GetChi2()+chi2);
 804
 805 }
 806