1 /**************************************************************************
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4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
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12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
18 /////////////////////////////////////////////////////////////
20 // Class for AOD reconstructed heavy-flavour cascades
22 // Author: X-M. Zhang, zhangxm@iopp.ccnu.edu.cn
23 /////////////////////////////////////////////////////////////
26 #include <TDatabasePDG.h>
27 #include <TClonesArray.h>
28 #include "AliAODMCParticle.h"
29 #include "AliAODRecoDecay.h"
30 #include "AliAODVertex.h"
31 #include "AliAODRecoDecayHF2Prong.h"
32 #include "AliAODRecoCascadeHF.h"
34 ClassImp(AliAODRecoCascadeHF)
35 //-----------------------------------------------------------------------------
37 AliAODRecoCascadeHF::AliAODRecoCascadeHF() :
38 AliAODRecoDecayHF2Prong()
41 // Default Constructor
44 //-----------------------------------------------------------------------------
45 AliAODRecoCascadeHF::AliAODRecoCascadeHF(AliAODVertex *vtx2, Short_t charge,
46 Double_t *px, Double_t *py, Double_t *pz,
47 Double_t *d0, Double_t *d0err, Double_t dca) :
48 AliAODRecoDecayHF2Prong(vtx2, px, py, pz, d0, d0err, dca)
51 // Constructor with AliAODVertex for decay vertex
55 //-----------------------------------------------------------------------------
56 AliAODRecoCascadeHF::AliAODRecoCascadeHF(AliAODVertex *vtx2, Short_t charge,
57 Double_t *d0, Double_t *d0err, Double_t dca) :
58 AliAODRecoDecayHF2Prong(vtx2, d0, d0err, dca)
61 // Constructor with decay vertex and without prongs momenta
65 //-----------------------------------------------------------------------------
66 AliAODRecoCascadeHF::AliAODRecoCascadeHF(const AliAODRecoCascadeHF &source) :
67 AliAODRecoDecayHF2Prong(source)
73 //-----------------------------------------------------------------------------
74 AliAODRecoCascadeHF &AliAODRecoCascadeHF::operator=(const AliAODRecoCascadeHF &source)
77 // assignment operator
79 if(&source == this) return *this;
81 AliAODRecoDecayHF2Prong::operator=(source);
85 //-----------------------------------------------------------------------------
86 AliAODRecoCascadeHF::~AliAODRecoCascadeHF()
92 //-----------------------------------------------------------------------------
93 Double_t AliAODRecoCascadeHF::InvMassDstarKpipi() const
96 // 3 prong invariant mass of the D0 daughters and the soft pion
100 e[0]=Get2Prong()->EProng(0,211);
101 e[1]=Get2Prong()->EProng(1,321);
103 e[0]=Get2Prong()->EProng(0,321);
104 e[1]=Get2Prong()->EProng(1,211);
108 Double_t esum = e[0]+e[1]+e[2];
109 Double_t minv = TMath::Sqrt(esum*esum-P()*P());
113 //----------------------------------------------------------------------------
114 Int_t AliAODRecoCascadeHF::MatchToMC(Int_t pdgabs,Int_t pdgabs2prong,
115 Int_t *pdgDg,Int_t *pdgDg2prong,
116 TClonesArray *mcArray, Bool_t isV0) const
119 // Check if this candidate is matched to a MC signal
121 // If yes, return label (>=0) of the AliAODMCParticle
124 Int_t ndg=GetNDaughters();
126 AliError("No daughters available");
130 Int_t lab2Prong = -1;
133 AliAODRecoDecayHF2Prong *the2Prong = Get2Prong();
134 lab2Prong = the2Prong->MatchToMC(pdgabs2prong,mcArray,2,pdgDg2prong);
136 AliAODv0 *theV0 = Getv0();
137 lab2Prong = theV0->MatchToMC(pdgabs2prong,mcArray,2,pdgDg2prong);
140 if(lab2Prong<0) return -1;
141 if (isV0) AliDebug(1,Form(" LabelV0=%d (%d -> %d %d)",lab2Prong,pdgabs2prong,pdgDg2prong[0],pdgDg2prong[1]));
143 Int_t dgLabels[10]={0,0,0,0,0,0,0,0,0,0};
145 // loop on daughters and write labels
146 for(Int_t i=0; i<ndg; i++) {
147 AliVTrack *trk = (AliVTrack*)GetDaughter(i);
148 Int_t lab = trk->GetLabel();
149 if(lab==-1) { // this daughter is the 2prong
151 } else if(lab<-1) continue;
155 Int_t finalLabel = AliAODRecoDecay::MatchToMC(pdgabs,mcArray,dgLabels,2,2,pdgDg);
156 if ( isV0 && (dgLabels[0]!=-1 || dgLabels[1]!=-1) ) {
157 if ( (pdgDg[0]==2212 && pdgDg[1]==310) ||
158 (pdgDg[0]==211 && pdgDg[1]==3122) ) {
159 AliDebug(1,Form(" LabelLc=%d (%d) -> LabelBachelor=%d (%d) LabelV0=%d (%d)",
161 dgLabels[0],pdgDg[0],dgLabels[1],pdgDg[1]));
162 } else if ( (pdgDg[1]==2212 && pdgDg[0]==310) ||
163 (pdgDg[1]==211 && pdgDg[0]==3122) ) {
164 AliDebug(1,Form(" LabelLc=%d (%d) -> LabelBachelor=%d (%d) LabelV0=%d (%d)",
166 dgLabels[1],pdgDg[1],dgLabels[0],pdgDg[0]));
173 //-----------------------------------------------------------------------------
174 Bool_t AliAODRecoCascadeHF::SelectDstar(const Double_t *cutsDstar,
175 const Double_t *cutsD0,
179 // cutsDstar[0] = inv. mass half width of D* [GeV]
180 // cutsDstar[1] = half width of (M_Kpipi-M_D0) [GeV]
181 // cutsDstar[2] = PtMin of pi_s [GeV/c]
182 // cutsDstar[3] = PtMax of pi_s [GeV/c]
183 // cutsDstar[4] = theta, angle between the pi_s and decay plane of the D0 [rad]
185 // cutsD0[0] = inv. mass half width [GeV]
186 // cutsD0[1] = dca [cm]
187 // cutsD0[2] = cosThetaStar
188 // cutsD0[3] = pTK [GeV/c]
189 // cutsD0[4] = pTPi [GeV/c]
190 // cutsD0[5] = d0K [cm] upper limit!
191 // cutsD0[6] = d0Pi [cm] upper limit!
192 // cutsD0[7] = d0d0 [cm^2]
193 // cutsD0[8] = cosThetaPoint
196 // check that the D0 passes the cuts
197 // (if we have a D*+, it has to pass as D0,
198 // if we have a D*-, it has to pass as D0bar)
201 Int_t okD0=0,okD0bar=0;
202 Get2Prong()->SelectD0(cutsD0,okD0,okD0bar);
203 if((Charge()==+1 && !okD0) || (Charge()==-1 && !okD0bar)) return kFALSE;
206 if( (PtProng(0)<cutsDstar[2]) || (PtProng(0)>cutsDstar[3]) ) return kFALSE;
208 Double_t mDstar = TDatabasePDG::Instance()->GetParticle(413)->Mass();
209 Double_t invmDstar = InvMassDstarKpipi();
210 if(TMath::Abs(mDstar-invmDstar)>cutsDstar[0]) return kFALSE;
212 Double_t mD0 = TDatabasePDG::Instance()->GetParticle(421)->Mass();
213 if(TMath::Abs((mDstar-mD0)-DeltaInvMass())>cutsDstar[1]) return kFALSE;
215 Double_t theta = AngleD0dkpPisoft();
216 if(theta>cutsDstar[4]) return kFALSE;
220 //-----------------------------------------------------------------------------
221 Bool_t AliAODRecoCascadeHF::SelectLctoV0(const Double_t *cutsLctoV0,
222 Bool_t okLck0sp, Bool_t okLcLpi) const
224 // cuts on Lambdac candidates to V0+bachelor
225 // (to be passed to AliAODRecoDecayHF3Prong::SelectLctoV0())
226 // 0 = inv. mass half width in K0s hypothesis [GeV]
227 // 1 = inv. mass half width in Lambda hypothesis [GeV]
228 // 2 = inv. mass V0 in K0s hypothesis half width [GeV]
229 // 3 = inv. mass V0 in Lambda hypothesis half width [GeV]
230 // 4 = pT min Bachelor track [GeV/c]
231 // 5 = pT min V0-Positive track [GeV/c]
232 // 6 = pT min V0-Negative track [GeV/c]
233 // 7 = dca cut on the V0 (cm)
234 // 8 = dca cut on the cascade (cm)
236 // if ( !Getv0() || !Getv0PositiveTrack() || !Getv0NegativeTrack() )
237 // { AliInfo(Form("Not adapted for ESDv0s, return true...")); return false; }
239 Double_t mLck0sp,mLcLpi;
240 okLck0sp=1; okLcLpi=1;
242 Double_t mLcPDG = TDatabasePDG::Instance()->GetParticle(4122)->Mass();
243 Double_t mk0sPDG = TDatabasePDG::Instance()->GetParticle(310)->Mass();
244 Double_t mLPDG = TDatabasePDG::Instance()->GetParticle(3122)->Mass();
247 double mk0s = Getv0()->MassK0Short();
248 mLck0sp = InvMassLctoK0sP();
251 double mlambda = Getv0()->MassLambda();
252 double malambda = Getv0()->MassAntiLambda();
253 mLcLpi = InvMassLctoLambdaPi();
256 // with k0s p hypothesis
257 if(TMath::Abs(mLck0sp-mLcPDG)>cutsLctoV0[0]) okLck0sp = 0;
258 // with Lambda pi hypothesis
259 if(TMath::Abs(mLcLpi-mLcPDG)>cutsLctoV0[1]) okLcLpi = 0;
261 // cuts on the v0 mass
262 if(TMath::Abs(mk0s-mk0sPDG)>cutsLctoV0[2]) okLck0sp = 0;
263 if( TMath::Abs(mlambda-mLPDG)>cutsLctoV0[3] &&
264 TMath::Abs(malambda-mLPDG)>cutsLctoV0[3] ) okLcLpi = 0;
266 if(!okLck0sp && !okLcLpi) return 0;
268 // cuts on the minimum pt of the tracks
269 if(TMath::Abs(GetBachelor()->Pt()) < cutsLctoV0[4]) return 0;
270 if(TMath::Abs(Getv0PositiveTrack()->Pt()) < cutsLctoV0[5]) return 0;
271 if(TMath::Abs(Getv0NegativeTrack()->Pt()) < cutsLctoV0[6]) return 0;
274 if(TMath::Abs(Getv0()->DcaV0Daughters()) > cutsLctoV0[7]) return 0;
276 // cut on the cascade dca
277 if( TMath::Abs(GetDCA(0))>cutsLctoV0[8] ||
278 TMath::Abs(Getv0()->DcaPosToPrimVertex())>cutsLctoV0[8] ||
279 TMath::Abs(Getv0()->DcaNegToPrimVertex())>cutsLctoV0[8] ) return 0;
284 //-----------------------------------------------------------------------------
285 Double_t AliAODRecoCascadeHF::AngleD0dkpPisoft() const {
287 // Angle of soft pion to D0 decay plane
290 TVector3 p3Trk0(Get2Prong()->PxProng(0),Get2Prong()->PyProng(0),Get2Prong()->PzProng(0)); // from D0
291 TVector3 p3Trk1(Get2Prong()->PxProng(1),Get2Prong()->PyProng(1),Get2Prong()->PzProng(1)); // from D0
292 TVector3 p3Trk2(PxProng(0),PyProng(0),PzProng(0)); // pi_s
294 TVector3 perp = p3Trk0.Cross(p3Trk1);
295 Double_t theta = p3Trk2.Angle(perp);
296 if(theta>(TMath::Pi()-theta)) theta = TMath::Pi() - theta;
297 theta = TMath::Pi()/2. - theta;
301 //-----------------------------------------------------------------------------
302 Bool_t AliAODRecoCascadeHF::TrigonometricalCut() const {
304 // Trigonometrical constraint
306 TVector3 p3Trk0(Get2Prong()->PxProng(0),Get2Prong()->PyProng(0),Get2Prong()->PzProng(0)); // from D0
307 TVector3 p3Trk1(Get2Prong()->PxProng(1),Get2Prong()->PyProng(1),Get2Prong()->PzProng(1)); // from D0
308 TVector3 p3Trk2(PxProng(0),PyProng(0),PzProng(0)); // pi_s
310 Double_t alpha = p3Trk0.Angle(p3Trk2);
311 Double_t beta = p3Trk1.Angle(p3Trk2);
313 Double_t cosphi01 = TMath::Cos(alpha) / TMath::Cos(AngleD0dkpPisoft());
314 Double_t cosphi02 = TMath::Cos(beta) / TMath::Cos(AngleD0dkpPisoft());
316 Double_t phi01 = TMath::ACos(cosphi01);
317 Double_t phi02 = TMath::ACos(cosphi02);
318 Double_t phi00 = p3Trk0.Angle(p3Trk1);
320 if((phi01>phi00) || (phi02>phi00)) return kFALSE;
324 //-----------------------------------------------------------------------------
325 Double_t AliAODRecoCascadeHF::DecayLengthV0() const
328 // Returns V0 decay length wrt primary vertex
331 AliAODv0 *v0 = (AliAODv0*)Getv0();
335 AliAODVertex *vtxPrimary = GetPrimaryVtx();
336 Double_t posVtx[3] = {0.,0.,0.};
337 vtxPrimary->GetXYZ(posVtx);
338 return v0->DecayLengthV0(posVtx);