PWG3/vertexingHF/AliAODRecoDecayHF4Prong.cxx

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  15
  16 /////////////////////////////////////////////////////////////
  17 //
  18 // Base class for AOD reconstructed heavy-flavour 4-prong decay
  19 //
  20 // Authors: G.E.Bruno Giuseppe.Bruno@to.infn.it, R.Romita Rossella.Romita@ba.infn.it
  21 /////////////////////////////////////////////////////////////
  22
  23 #include <TDatabasePDG.h>
  24 #include "AliAODRecoDecayHF.h"
  25 #include "AliAODRecoDecayHF4Prong.h"
  26
  27 ClassImp(AliAODRecoDecayHF4Prong)
  28
  29 //--------------------------------------------------------------------------
  30 AliAODRecoDecayHF4Prong::AliAODRecoDecayHF4Prong() :
  31   AliAODRecoDecayHF(),
  32   fDist12toPrim(0),
  33   fDist3toPrim(0),
  34   fDist4toPrim(0)
  35 {
  36   //
  37   // Default Constructor
  38   //
  39 }
  40 //--------------------------------------------------------------------------
  41 AliAODRecoDecayHF4Prong::AliAODRecoDecayHF4Prong(AliAODVertex *vtx2,
  42                                                  Double_t *px,Double_t *py,Double_t *pz,
  43                                                  Double_t *d0,Double_t *d0err,
  44                                                  Double_t *dca, //Double_t sigvert,
  45                                                  Double_t dist12,Double_t dist3,
  46                                                  Double_t dist4,
  47                                                  Short_t charge) :
  48   AliAODRecoDecayHF(vtx2,4,charge,px,py,pz,d0,d0err),
  49   // fSigmaVert(sigvert),
  50   fDist12toPrim(dist12),
  51   fDist3toPrim(dist3),
  52   fDist4toPrim(dist4)
  53 {
  54   //
  55   // Constructor with AliAODVertex for decay vertex
  56   //
  57   SetDCAs(6,dca);
  58 }
  59 //--------------------------------------------------------------------------
  60 AliAODRecoDecayHF4Prong::AliAODRecoDecayHF4Prong(AliAODVertex *vtx2,
  61                                                  Double_t *d0,Double_t *d0err,
  62                                                  Double_t *dca, //Double_t sigvert,
  63                                                  Double_t dist12,Double_t dist3,
  64                                                  Double_t dist4,
  65                                                  Short_t charge) :
  66   AliAODRecoDecayHF(vtx2,4,charge,d0,d0err),
  67   //fSigmaVert(sigvert),
  68   fDist12toPrim(dist12),
  69   fDist3toPrim(dist3),
  70   fDist4toPrim(dist4)
  71 {
  72   //
  73   // Constructor with AliAODVertex for decay vertex and without prongs momenta
  74   //
  75   SetDCAs(6,dca);
  76 }
  77 //--------------------------------------------------------------------------
  78 AliAODRecoDecayHF4Prong::AliAODRecoDecayHF4Prong(const AliAODRecoDecayHF4Prong &source) :
  79   AliAODRecoDecayHF(source),
  80   //fSigmaVert(source.fSigmaVert),
  81   fDist12toPrim(source.fDist12toPrim),
  82   fDist3toPrim(source.fDist3toPrim),
  83   fDist4toPrim(source.fDist4toPrim)
  84 {
  85   //
  86   // Copy constructor
  87   //
  88 }
  89 //--------------------------------------------------------------------------
  90 AliAODRecoDecayHF4Prong &AliAODRecoDecayHF4Prong::operator=(const AliAODRecoDecayHF4Prong &source)
  91 {
  92   //
  93   // assignment operator
  94   //
  95   if(&source == this) return *this;
  96
  97   AliAODRecoDecayHF::operator=(source);
  98
  99   fDist12toPrim= source.fDist12toPrim;
 100   fDist3toPrim= source.fDist3toPrim;
 101   fDist4toPrim= source.fDist4toPrim;
 102   //fSigmaVert= source.fSigmaVert;
 103
 104   return *this;
 105 }
 106 //--------------------------------------------------------------------------
 107 void AliAODRecoDecayHF4Prong::InvMassD0(Double_t mD0[2]) const {
 108   //
 109   // Mass for the two D0 hypotheses
 110   //
 111   UInt_t pdg[4];
 112   pdg[0]=211; pdg[1]=321; pdg[2]=211; pdg[3]=211;
 113   mD0[0]=InvMass(4,pdg);
 114   pdg[1]=211; pdg[3]=321;
 115   mD0[1]=InvMass(4,pdg);
 116
 117   return;
 118 }
 119 //--------------------------------------------------------------------------
 120 void AliAODRecoDecayHF4Prong::InvMassD0bar(Double_t mD0bar[2]) const {
 121   //
 122   // Mass for the two D0bar hypotheses
 123   //
 124   UInt_t pdg[4];
 125   pdg[0]=321; pdg[1]=211; pdg[2]=211; pdg[3]=211;
 126   mD0bar[0]=InvMass(4,pdg);
 127   pdg[0]=211; pdg[2]=321;
 128   mD0bar[1]=InvMass(4,pdg);
 129
 130   return;
 131 }
 132 //--------------------------------------------------------------------------
 133
 134 Bool_t AliAODRecoDecayHF4Prong::SelectD0(const Double_t *cuts,Int_t &okD0,Int_t &okD0bar) const
 135 {
 136   //
 137   // This function compares the D0 with a set of cuts:
 138   //
 139   // cuts[0] = D0 invariant mass
 140   // cuts[1] = DCA between opposite sign tracks
 141   // cuts[2] = Distance between primary and two tracks vertex fDist12toPrim
 142   // cuts[3] = Distance between primary and three tracks vertex fDist3toPrim
 143   // cuts[4] = Distance between primary and two tracks vertex fDist4toPrim
 144   // cuts[5] = Cosinus of the pointing angle
 145   // cuts[6] = Transverse momentum of the D0 candidate
 146   // cuts[7] = Mass Pi+Pi- = mass of the rho0
 147   // cuts[8] = PID cut (one K in the quadruplet)
 148   //
 149   // If candidate D0 does not pass the cuts return kFALSE
 150   //
 151
 152   okD0=0; okD0bar=0;
 153   Double_t mD0PDG = TDatabasePDG::Instance()->GetParticle(421)->Mass();
 154   Double_t mD0[2];
 155   Double_t mD0bar[2];
 156   InvMassD0(mD0);
 157   InvMassD0bar(mD0bar);
 158   Bool_t goodMass=kFALSE;
 159   if(TMath::Abs(mD0[0]-mD0PDG)<=cuts[0]) {goodMass=kTRUE; okD0=1;}
 160   if(TMath::Abs(mD0[1]-mD0PDG)<=cuts[0]) {goodMass=kTRUE; okD0=1;}
 161   if(TMath::Abs(mD0bar[0]-mD0PDG)<=cuts[0]) {goodMass=kTRUE; okD0bar=1;}
 162   if(TMath::Abs(mD0bar[1]-mD0PDG)<=cuts[0]) {goodMass=kTRUE; okD0bar=1;}
 163   if(!goodMass) return kFALSE;
 164
 165   //DCA btw opposite sign tracks
 166   if(cuts[1]>0.){
 167     if(GetDCA(0)>cuts[1]) return kFALSE;
 168     if(GetDCA(1)>cuts[1]) return kFALSE;
 169     if(GetDCA(2)>cuts[1]) return kFALSE;
 170     if(GetDCA(3)>cuts[1]) return kFALSE;
 171     if(GetDCA(4)>cuts[1]) return kFALSE;
 172     if(GetDCA(5)>cuts[1]) return kFALSE;
 173   }
 174   //2track cuts
 175   if(cuts[2]>0.){
 176     if(fDist12toPrim>10.)return kFALSE;
 177     if(fDist12toPrim<cuts[2])return kFALSE;
 178   }
 179   //3track cuts
 180   if(cuts[3]>0.){
 181     if(fDist3toPrim<cuts[3])return kFALSE;
 182   }
 183   //4track cuts
 184   if(cuts[4]>0.){
 185     if(fDist4toPrim<cuts[4])return kFALSE;
 186   }
 187   if(cuts[5]>-1.1){
 188     if(CosPointingAngle()<cuts[5])return kFALSE;
 189   }
 190   if(cuts[6]>0.){
 191     if(Pt()<cuts[6])return kFALSE;
 192   }
 193   if(cuts[7]>0.){
 194     Double_t massD0[2];
 195     Double_t massD0bar[2];
 196     Bool_t good=CutRhoMass(massD0,massD0bar,cuts[0],cuts[7]);
 197     if(!good) return kFALSE;
 198   }
 199
 200   return kTRUE;
 201 }
 202 //----------------------------------------------------------------------------
 203 Bool_t AliAODRecoDecayHF4Prong::CutRhoMass(Double_t massD0[2],Double_t massD0bar[2],Double_t cutMass,Double_t cutRho) const
 204 {
 205   //
 206   // Cut on rho->pipi mass for any of the pairs
 207   //
 208   Bool_t isGood=kFALSE;
 209   Int_t nprongs=4;
 210   for(Int_t i=0;i<2;i++){massD0[i]=0.;massD0bar[i]=0.;}
 211   Bool_t isRho=kFALSE;
 212   Bool_t isTrue=kFALSE;
 213   Double_t mPDG=TDatabasePDG::Instance()->GetParticle(421)->Mass();
 214   Double_t mPDGRho=TDatabasePDG::Instance()->GetParticle(113)->Mass();
 215   Double_t minv01=InvMassRho(0,1);
 216   if(TMath::Abs(minv01-mPDGRho)<cutRho) isRho=kTRUE;
 217   if(isRho){
 218     UInt_t pdg1[4]={211,211,321,211};
 219     Double_t mass1=InvMass(nprongs,pdg1);
 220     if(TMath::Abs(mass1-mPDG)<cutMass) {isTrue=kTRUE;isGood=kTRUE;}
 221     if(isTrue) massD0bar[1]=mass1;
 222     isTrue=kFALSE;
 223     UInt_t pdg2[4]={211,211,211,321};
 224     Double_t mass2=InvMass(4,pdg2);
 225     if(TMath::Abs(mass2-mPDG)<cutMass) {isTrue=kTRUE;isGood=kTRUE;}
 226     if(isTrue) massD0[1]=mass2;
 227     isTrue=kFALSE;
 228   }
 229   Double_t minv03=InvMassRho(0,3);
 230   if(TMath::Abs(minv03-mPDGRho)<cutRho) isRho=kTRUE;
 231   if(isRho){
 232     UInt_t pdg1[4]={211,211,321,211};
 233     Double_t mass1=InvMass(4,pdg1);
 234     if(TMath::Abs(mass1-mPDG)<cutMass) {isTrue=kTRUE;isGood=kTRUE;}
 235     if(isTrue) massD0bar[1]=mass1;
 236     isTrue=kFALSE;
 237     UInt_t pdg2[4]={211,321,211,211};
 238     Double_t mass2=InvMass(4,pdg2);
 239     if(TMath::Abs(mass2-mPDG)<cutMass) {isTrue=kTRUE;isGood=kTRUE;}
 240     if(isTrue) massD0[0]=mass2;
 241     isTrue=kFALSE;
 242   }
 243   Double_t minv12=InvMassRho(1,2);
 244   if(TMath::Abs(minv12-mPDGRho)<cutRho) isRho=kTRUE;
 245   if(isRho){
 246     UInt_t pdg1[4]={321,211,211,211};
 247     Double_t mass1=InvMass(4,pdg1);
 248     if(TMath::Abs(mass1-mPDG)<cutMass) {isTrue=kTRUE;isGood=kTRUE;}
 249     if(isTrue) massD0bar[0]=mass1;
 250     isTrue=kFALSE;
 251     UInt_t pdg2[4]={211,211,211,321};
 252     Double_t mass2=InvMass(4,pdg2);
 253     if(TMath::Abs(mass2-mPDG)<cutMass) {isTrue=kTRUE;isGood=kTRUE;}
 254     if(isTrue) massD0[1]=mass2;
 255     isTrue=kFALSE;
 256   }
 257   Double_t minv23=InvMassRho(2,3);
 258   if(TMath::Abs(minv23-mPDGRho)<cutRho) isRho=kTRUE;
 259   if(isRho){
 260     UInt_t pdg1[4]={321,211,211,211};
 261     Double_t mass1=InvMass(4,pdg1);
 262     if(TMath::Abs(mass1-mPDG)<cutMass) {isTrue=kTRUE;isGood=kTRUE;}
 263     if(isTrue) massD0bar[0]=mass1;
 264     isTrue=kFALSE;
 265     UInt_t pdg2[4]={211,321,211,211};
 266     Double_t mass2=InvMass(4,pdg2);
 267     if(TMath::Abs(mass2-mPDG)<cutMass) {isTrue=kTRUE;isGood=kTRUE;}
 268     if(isTrue) massD0[0]=mass2;
 269     isTrue=kFALSE;
 270   }
 271   return isGood;
 272 }