1 /**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
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 *
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 **************************************************************************/
18 //-------------------------------------------------------------------------
19 // Implementation of the ESD V0 vertex class
20 // This class is part of the Event Data Summary
21 // set of classes and contains information about
22 // V0 kind vertexes generated by a neutral particle
23 // Origin: Iouri Belikov, IReS, Strasbourg, Jouri.Belikov@cern.ch
24 // Modified by: Marian Ivanov, CERN, Marian.Ivanov@cern.ch
25 // and Boris Hippolyte,IPHC, hippolyt@in2p3.fr
26 //-------------------------------------------------------------------------
28 #include <Riostream.h>
30 #include <TDatabasePDG.h>
32 #include <TParticlePDG.h>
37 #include "AliExternalTrackParam.h"
41 const AliESDV0Params AliESDv0::fgkParams;
43 AliESDv0::AliESDv0() :
47 fEffMass(TDatabasePDG::Instance()->GetParticle(kK0Short)->Mass()),
65 //--------------------------------------------------------------------
66 // Default constructor (K0s)
67 //--------------------------------------------------------------------
69 for (Int_t i=0; i<3; i++) {
75 for (Int_t i=0; i<6; i++) {
79 for (Int_t i=0;i<6;i++){fClusters[0][i]=0; fClusters[1][i]=0;}
80 fNormDCAPrim[0]=fNormDCAPrim[1]=0;
81 for (Int_t i=0;i<3;i++){fAngle[i]=0;}
82 for (Int_t i=0;i<4;i++){fCausality[i]=0;}
85 AliESDv0::AliESDv0(const AliESDv0& v0) :
89 fEffMass(v0.fEffMass),
90 fDcaV0Daughters(v0.fDcaV0Daughters),
93 fDistSigma(v0.fDistSigma),
94 fChi2Before(v0.fChi2Before),
95 fChi2After(v0.fChi2After),
96 fPointAngleFi(v0.fPointAngleFi),
97 fPointAngleTh(v0.fPointAngleTh),
98 fPointAngle(v0.fPointAngle),
99 fPdgCode(v0.fPdgCode),
103 fNBefore(v0.fNBefore),
105 fOnFlyStatus(v0.fOnFlyStatus)
107 //--------------------------------------------------------------------
108 // The copy constructor
109 //--------------------------------------------------------------------
111 for (int i=0; i<3; i++) {
112 fPos[i] = v0.fPos[i];
113 fNmom[i] = v0.fNmom[i];
114 fPmom[i] = v0.fPmom[i];
116 for (int i=0; i<6; i++) {
117 fPosCov[i] = v0.fPosCov[i];
120 for (Int_t i=0; i<2; i++) {
121 fNormDCAPrim[i]=v0.fNormDCAPrim[i];
123 for (Int_t i=0;i<6;i++){
124 fClusters[0][i]=v0.fClusters[0][i];
125 fClusters[1][i]=v0.fClusters[1][i];
127 for (Int_t i=0;i<3;i++){
128 fAngle[i]=v0.fAngle[i];
130 for (Int_t i=0;i<4;i++){fCausality[i]=v0.fCausality[i];}
134 AliESDv0::AliESDv0(const AliExternalTrackParam &t1, Int_t i1,
135 const AliExternalTrackParam &t2, Int_t i2) :
139 fEffMass(TDatabasePDG::Instance()->GetParticle(kK0Short)->Mass()),
157 //--------------------------------------------------------------------
158 // Main constructor (K0s)
159 //--------------------------------------------------------------------
161 for (Int_t i=0; i<6; i++) {
165 //Trivial estimation of the vertex parameters
166 Double_t alpha=t1.GetAlpha(), cs=TMath::Cos(alpha), sn=TMath::Sin(alpha);
169 Double_t px1=tmp[0], py1=tmp[1], pz1=tmp[2];
171 Double_t x1=tmp[0], y1=tmp[1], z1=tmp[2];
172 const Double_t ss=0.0005*0.0005;//a kind of a residual misalignment precision
173 Double_t sx1=sn*sn*t1.GetSigmaY2()+ss, sy1=cs*cs*t1.GetSigmaY2()+ss;
176 alpha=t2.GetAlpha(); cs=TMath::Cos(alpha); sn=TMath::Sin(alpha);
178 Double_t px2=tmp[0], py2=tmp[1], pz2=tmp[2];
180 Double_t x2=tmp[0], y2=tmp[1], z2=tmp[2];
181 Double_t sx2=sn*sn*t2.GetSigmaY2()+ss, sy2=cs*cs*t2.GetSigmaY2()+ss;
183 Double_t sz1=t1.GetSigmaZ2(), sz2=t2.GetSigmaZ2();
184 Double_t wx1=sx2/(sx1+sx2), wx2=1.- wx1;
185 Double_t wy1=sy2/(sy1+sy2), wy2=1.- wy1;
186 Double_t wz1=sz2/(sz1+sz2), wz2=1.- wz1;
187 fPos[0]=wx1*x1 + wx2*x2; fPos[1]=wy1*y1 + wy2*y2; fPos[2]=wz1*z1 + wz2*z2;
189 //fPos[0]=0.5*(x1+x2); fPos[1]=0.5*(y1+y2); fPos[2]=0.5*(z1+z2);
190 fNmom[0]=px1; fNmom[1]=py1; fNmom[2]=pz1;
191 fPmom[0]=px2; fPmom[1]=py2; fPmom[2]=pz2;
193 for (Int_t i=0;i<6;i++){fClusters[0][i]=0; fClusters[1][i]=0;}
194 fNormDCAPrim[0]=fNormDCAPrim[1]=0;
195 for (Int_t i=0;i<3;i++){fAngle[i]=0;}
196 for (Int_t i=0;i<4;i++){fCausality[i]=0;}
199 AliESDv0& AliESDv0::operator=(const AliESDv0 &v0)
201 //--------------------------------------------------------------------
202 // The assignment operator
203 //--------------------------------------------------------------------
205 if(this==&v0)return *this;
206 AliVParticle::operator=(v0);
207 fParamN = v0.fParamN;
208 fParamP = v0.fParamP;
209 fEffMass = v0.fEffMass;
210 fDcaV0Daughters = v0.fDcaV0Daughters;
211 fChi2V0 = v0.fChi2V0;
213 fDistSigma = v0.fDistSigma;
214 fChi2Before = v0.fChi2Before;
215 fChi2After = v0.fChi2After;
216 fPointAngleFi = v0.fPointAngleFi;
217 fPointAngleTh = v0.fPointAngleTh;
218 fPointAngle = v0.fPointAngle;
219 fPdgCode = v0.fPdgCode;
222 fStatus = v0.fStatus;
223 fNBefore = v0.fNBefore;
224 fNAfter = v0.fNAfter;
225 fOnFlyStatus = v0.fOnFlyStatus;
227 for (int i=0; i<3; i++) {
228 fPos[i] = v0.fPos[i];
229 fNmom[i] = v0.fNmom[i];
230 fPmom[i] = v0.fPmom[i];
232 for (int i=0; i<6; i++) {
233 fPosCov[i] = v0.fPosCov[i];
235 for (Int_t i=0; i<2; i++) {
236 fNormDCAPrim[i]=v0.fNormDCAPrim[i];
238 for (Int_t i=0;i<6;i++){
239 fClusters[0][i]=v0.fClusters[0][i];
240 fClusters[1][i]=v0.fClusters[1][i];
242 for (Int_t i=0;i<3;i++){
243 fAngle[i]=v0.fAngle[i];
245 for (Int_t i=0;i<4;i++){fCausality[i]=v0.fCausality[i];}
250 void AliESDv0::Copy(TObject& obj) const {
252 // this overwrites the virtual TOBject::Copy()
253 // to allow run time copying without casting
256 if(this==&obj)return;
257 AliESDv0 *robj = dynamic_cast<AliESDv0*>(&obj);
258 if(!robj)return; // not an aliesesv0
262 AliESDv0::~AliESDv0(){
263 //--------------------------------------------------------------------
265 //--------------------------------------------------------------------
268 // Start with AliVParticle functions
269 Double_t AliESDv0::E() const {
270 //--------------------------------------------------------------------
271 // This gives the energy assuming the ChangeMassHypothesis was called
272 //--------------------------------------------------------------------
276 Double_t AliESDv0::Y() const {
277 //--------------------------------------------------------------------
278 // This gives the energy assuming the ChangeMassHypothesis was called
279 //--------------------------------------------------------------------
283 // Then extend AliVParticle functions
284 Double_t AliESDv0::E(Int_t pdg) const {
285 //--------------------------------------------------------------------
286 // This gives the energy with the particle hypothesis as argument
287 //--------------------------------------------------------------------
288 Double_t mass = TDatabasePDG::Instance()->GetParticle(pdg)->Mass();
289 return TMath::Sqrt(mass*mass+P()*P());
292 Double_t AliESDv0::Y(Int_t pdg) const {
293 //--------------------------------------------------------------------
294 // This gives the rapidity with the particle hypothesis as argument
295 //--------------------------------------------------------------------
296 return 0.5*TMath::Log((E(pdg)+Pz())/(E(pdg)-Pz()+1.e-13));
299 // Now the functions for analysis consistency
300 Double_t AliESDv0::RapK0Short() const {
301 //--------------------------------------------------------------------
302 // This gives the pseudorapidity assuming a K0s particle
303 //--------------------------------------------------------------------
307 Double_t AliESDv0::RapLambda() const {
308 //--------------------------------------------------------------------
309 // This gives the pseudorapidity assuming a (Anti) Lambda particle
310 //--------------------------------------------------------------------
314 Double_t AliESDv0::AlphaV0() const {
315 //--------------------------------------------------------------------
316 // This gives the Armenteros-Podolanski alpha
317 //--------------------------------------------------------------------
318 TVector3 momNeg(fNmom[0],fNmom[1],fNmom[2]);
319 TVector3 momPos(fPmom[0],fPmom[1],fPmom[2]);
320 TVector3 momTot(Px(),Py(),Pz());
322 Double_t QlNeg = momNeg.Dot(momTot)/momTot.Mag();
323 Double_t QlPos = momNeg.Dot(momTot)/momTot.Mag();
325 return 1.-2./(1.+QlNeg/QlPos);
328 Double_t AliESDv0::PtArmV0() const {
329 //--------------------------------------------------------------------
330 // This gives the Armenteros-Podolanski ptarm
331 //--------------------------------------------------------------------
332 TVector3 momNeg(fNmom[0],fNmom[1],fNmom[2]);
333 TVector3 momTot(Px(),Py(),Pz());
335 return momNeg.Perp(momTot);
338 // Eventually the older functions
339 Double_t AliESDv0::ChangeMassHypothesis(Int_t code) {
340 //--------------------------------------------------------------------
341 // This function changes the mass hypothesis for this V0
342 // and returns the "kinematical quality" of this hypothesis
343 //--------------------------------------------------------------------
345 Double_t piMass=TDatabasePDG::Instance()->GetParticle(kPiPlus)->Mass();
347 Double_t prMass=TDatabasePDG::Instance()->GetParticle(kProton)->Mass();
349 Double_t k0Mass=TDatabasePDG::Instance()->GetParticle(kK0Short)->Mass();
351 Double_t l0Mass=TDatabasePDG::Instance()->GetParticle(kLambda0)->Mass();
353 Double_t nmass=piMass, pmass=piMass, mass=k0Mass, ps=0.206;
359 nmass=piMass; pmass=prMass; mass=l0Mass; ps=0.101; break;
361 pmass=piMass; nmass=prMass; mass=l0Mass; ps=0.101; break;
365 AliError("invalide PDG code ! Assuming K0s...");
370 Double_t pxn=fNmom[0], pyn=fNmom[1], pzn=fNmom[2];
371 Double_t pxp=fPmom[0], pyp=fPmom[1], pzp=fPmom[2];
373 Double_t en=TMath::Sqrt(nmass*nmass + pxn*pxn + pyn*pyn + pzn*pzn);
374 Double_t ep=TMath::Sqrt(pmass*pmass + pxp*pxp + pyp*pyp + pzp*pzp);
375 Double_t pxl=pxn+pxp, pyl=pyn+pyp, pzl=pzn+pzp;
376 Double_t pl=TMath::Sqrt(pxl*pxl + pyl*pyl + pzl*pzl);
378 fEffMass=TMath::Sqrt((en+ep)*(en+ep)-pl*pl);
380 Double_t beta=pl/(en+ep);
381 Double_t pln=(pxn*pxl + pyn*pyl + pzn*pzl)/pl;
382 Double_t plp=(pxp*pxl + pyp*pyl + pzp*pzl)/pl;
384 Double_t pt2=pxp*pxp + pyp*pyp + pzp*pzp - plp*plp;
386 Double_t a=(plp-pln)/(plp+pln);
387 a -= (pmass*pmass-nmass*nmass)/(mass*mass);
388 a = 0.25*beta*beta*mass*mass*a*a + pt2;
394 void AliESDv0::GetPxPyPz(Double_t &px, Double_t &py, Double_t &pz) const {
395 //--------------------------------------------------------------------
396 // This function returns V0's momentum (global)
397 //--------------------------------------------------------------------
398 px=fNmom[0]+fPmom[0];
399 py=fNmom[1]+fPmom[1];
400 pz=fNmom[2]+fPmom[2];
403 void AliESDv0::GetXYZ(Double_t &x, Double_t &y, Double_t &z) const {
404 //--------------------------------------------------------------------
405 // This function returns V0's position (global)
406 //--------------------------------------------------------------------
412 Float_t AliESDv0::GetD(Double_t x0, Double_t y0, Double_t z0) const {
413 //--------------------------------------------------------------------
414 // This function returns V0's impact parameter
415 //--------------------------------------------------------------------
416 Double_t x=fPos[0],y=fPos[1],z=fPos[2];
417 Double_t px=fNmom[0]+fPmom[0];
418 Double_t py=fNmom[1]+fPmom[1];
419 Double_t pz=fNmom[2]+fPmom[2];
421 Double_t dx=(y0-y)*pz - (z0-z)*py;
422 Double_t dy=(x0-x)*pz - (z0-z)*px;
423 Double_t dz=(x0-x)*py - (y0-y)*px;
424 Double_t d=TMath::Sqrt((dx*dx+dy*dy+dz*dz)/(px*px+py*py+pz*pz));
429 Float_t AliESDv0::GetV0CosineOfPointingAngle(Double_t& refPointX, Double_t& refPointY, Double_t& refPointZ) const {
430 // calculates the pointing angle of the V0 wrt a reference point
432 Double_t momV0[3]; //momentum of the V0
433 GetPxPyPz(momV0[0],momV0[1],momV0[2]);
435 Double_t deltaPos[3]; //vector between the reference point and the V0 vertex
436 deltaPos[0] = fPos[0] - refPointX;
437 deltaPos[1] = fPos[1] - refPointY;
438 deltaPos[2] = fPos[2] - refPointZ;
440 Double_t momV02 = momV0[0]*momV0[0] + momV0[1]*momV0[1] + momV0[2]*momV0[2];
441 Double_t deltaPos2 = deltaPos[0]*deltaPos[0] + deltaPos[1]*deltaPos[1] + deltaPos[2]*deltaPos[2];
443 Double_t cosinePointingAngle = (deltaPos[0]*momV0[0] +
444 deltaPos[1]*momV0[1] +
445 deltaPos[2]*momV0[2] ) /
446 TMath::Sqrt(momV02 * deltaPos2);
448 return cosinePointingAngle;
452 // **** The following functions need to be revised
454 void AliESDv0::GetPosCov(Double_t cov[6]) const {
456 for (Int_t i=0; i<6; ++i) cov[i] = fPosCov[i];
460 Double_t AliESDv0::GetSigmaY(){
462 // return sigmay in y at vertex position using covariance matrix
464 const Double_t * cp = fParamP.GetCovariance();
465 const Double_t * cm = fParamN.GetCovariance();
466 Double_t sigmay = cp[0]+cm[0]+ cp[5]*(fParamP.GetX()-fRr)*(fParamP.GetX()-fRr)+ cm[5]*(fParamN.GetX()-fRr)*(fParamN.GetX()-fRr);
467 return (sigmay>0) ? TMath::Sqrt(sigmay):100;
470 Double_t AliESDv0::GetSigmaZ(){
472 // return sigmay in y at vertex position using covariance matrix
474 const Double_t * cp = fParamP.GetCovariance();
475 const Double_t * cm = fParamN.GetCovariance();
476 Double_t sigmaz = cp[2]+cm[2]+ cp[9]*(fParamP.GetX()-fRr)*(fParamP.GetX()-fRr)+ cm[9]*(fParamN.GetX()-fRr)*(fParamN.GetX()-fRr);
477 return (sigmaz>0) ? TMath::Sqrt(sigmaz):100;
480 Double_t AliESDv0::GetSigmaD0(){
482 // Sigma parameterization using covariance matrix
484 // sigma of distance between two tracks in vertex position
485 // sigma of DCA is proportianal to sigmaD0
486 // factor 2 difference is explained by the fact that the DCA is calculated at the position
487 // where the tracks as closest together ( not exact position of the vertex)
489 const Double_t * cp = fParamP.GetCovariance();
490 const Double_t * cm = fParamN.GetCovariance();
491 Double_t sigmaD0 = cp[0]+cm[0]+cp[2]+cm[2]+fgkParams.fPSigmaOffsetD0*fgkParams.fPSigmaOffsetD0;
492 sigmaD0 += ((fParamP.GetX()-fRr)*(fParamP.GetX()-fRr))*(cp[5]+cp[9]);
493 sigmaD0 += ((fParamN.GetX()-fRr)*(fParamN.GetX()-fRr))*(cm[5]+cm[9]);
494 return (sigmaD0>0)? TMath::Sqrt(sigmaD0):100;
498 Double_t AliESDv0::GetSigmaAP0(){
500 //Sigma parameterization using covariance matrices
502 Double_t prec = TMath::Sqrt((fNmom[0]+fPmom[0])*(fNmom[0]+fPmom[0])
503 +(fNmom[1]+fPmom[1])*(fNmom[1]+fPmom[1])
504 +(fNmom[2]+fPmom[2])*(fNmom[2]+fPmom[2]));
505 Double_t normp = TMath::Sqrt(fPmom[0]*fPmom[0]+fPmom[1]*fPmom[1]+fPmom[2]*fPmom[2])/prec; // fraction of the momenta
506 Double_t normm = TMath::Sqrt(fNmom[0]*fNmom[0]+fNmom[1]*fNmom[1]+fNmom[2]*fNmom[2])/prec;
507 const Double_t * cp = fParamP.GetCovariance();
508 const Double_t * cm = fParamN.GetCovariance();
509 Double_t sigmaAP0 = fgkParams.fPSigmaOffsetAP0*fgkParams.fPSigmaOffsetAP0; // minimal part
510 sigmaAP0 += (cp[5]+cp[9])*(normp*normp)+(cm[5]+cm[9])*(normm*normm); // angular resolution part
511 Double_t sigmaAP1 = GetSigmaD0()/(TMath::Abs(fRr)+0.01); // vertex position part
512 sigmaAP0 += 0.5*sigmaAP1*sigmaAP1;
513 return (sigmaAP0>0)? TMath::Sqrt(sigmaAP0):100;
516 Double_t AliESDv0::GetEffectiveSigmaD0(){
518 // minimax - effective Sigma parameterization
519 // p12 effective curvature and v0 radius postion used as parameters
521 Double_t p12 = TMath::Sqrt(fParamP.GetParameter()[4]*fParamP.GetParameter()[4]+
522 fParamN.GetParameter()[4]*fParamN.GetParameter()[4]);
523 Double_t sigmaED0= TMath::Max(TMath::Sqrt(fRr)-fgkParams.fPSigmaRminDE,0.0)*fgkParams.fPSigmaCoefDE*p12*p12;
526 sigmaED0 = TMath::Sqrt(sigmaED0+fgkParams.fPSigmaOffsetDE*fgkParams.fPSigmaOffsetDE);
527 return (sigmaED0<fgkParams.fPSigmaMaxDE) ? sigmaED0: fgkParams.fPSigmaMaxDE;
531 Double_t AliESDv0::GetEffectiveSigmaAP0(){
533 // effective Sigma parameterization of point angle resolution
535 Double_t p12 = TMath::Sqrt(fParamP.GetParameter()[4]*fParamP.GetParameter()[4]+
536 fParamN.GetParameter()[4]*fParamN.GetParameter()[4]);
537 Double_t sigmaAPE= fgkParams.fPSigmaBase0APE;
538 sigmaAPE+= fgkParams.fPSigmaR0APE/(fgkParams.fPSigmaR1APE+fRr);
539 sigmaAPE*= (fgkParams.fPSigmaP0APE+fgkParams.fPSigmaP1APE*p12);
540 sigmaAPE = TMath::Min(sigmaAPE,fgkParams.fPSigmaMaxAPE);
545 Double_t AliESDv0::GetMinimaxSigmaAP0(){
547 // calculate mini-max effective sigma of point angle resolution
549 //compv0->fTree->SetAlias("SigmaAP2","max(min((SigmaAP0+SigmaAPE0)*0.5,1.5*SigmaAPE0),0.5*SigmaAPE0+0.003)");
550 Double_t effectiveSigma = GetEffectiveSigmaAP0();
551 Double_t sigmaMMAP = 0.5*(GetSigmaAP0()+effectiveSigma);
552 sigmaMMAP = TMath::Min(sigmaMMAP, fgkParams.fPMaxFractionAP0*effectiveSigma);
553 sigmaMMAP = TMath::Max(sigmaMMAP, fgkParams.fPMinFractionAP0*effectiveSigma+fgkParams.fPMinAP0);
556 Double_t AliESDv0::GetMinimaxSigmaD0(){
558 // calculate mini-max sigma of dca resolution
560 //compv0->fTree->SetAlias("SigmaD2","max(min((SigmaD0+SigmaDE0)*0.5,1.5*SigmaDE0),0.5*SigmaDE0)");
561 Double_t effectiveSigma = GetEffectiveSigmaD0();
562 Double_t sigmaMMD0 = 0.5*(GetSigmaD0()+effectiveSigma);
563 sigmaMMD0 = TMath::Min(sigmaMMD0, fgkParams.fPMaxFractionD0*effectiveSigma);
564 sigmaMMD0 = TMath::Max(sigmaMMD0, fgkParams.fPMinFractionD0*effectiveSigma+fgkParams.fPMinD0);
569 Double_t AliESDv0::GetLikelihoodAP(Int_t mode0, Int_t mode1){
571 // get likelihood for point angle
573 Double_t sigmaAP = 0.007; //default sigma
576 sigmaAP = GetSigmaAP0(); // mode 0 - covariance matrix estimates used
579 sigmaAP = GetEffectiveSigmaAP0(); // mode 1 - effective sigma used
582 sigmaAP = GetMinimaxSigmaAP0(); // mode 2 - minimax sigma
585 Double_t apNorm = TMath::Min(TMath::ACos(fPointAngle)/sigmaAP,50.);
586 //normalized point angle, restricted - because of overflow problems in Exp
587 Double_t likelihood = 0;
590 likelihood = TMath::Exp(-0.5*apNorm*apNorm);
594 likelihood = (TMath::Exp(-0.5*apNorm*apNorm)+0.5* TMath::Exp(-0.25*apNorm*apNorm))/1.5;
598 likelihood = (TMath::Exp(-0.5*apNorm*apNorm)+0.5* TMath::Exp(-0.25*apNorm*apNorm)+0.25*TMath::Exp(-0.125*apNorm*apNorm))/1.75;
605 Double_t AliESDv0::GetLikelihoodD(Int_t mode0, Int_t mode1){
607 // get likelihood for DCA
609 Double_t sigmaD = 0.03; //default sigma
612 sigmaD = GetSigmaD0(); // mode 0 - covariance matrix estimates used
615 sigmaD = GetEffectiveSigmaD0(); // mode 1 - effective sigma used
618 sigmaD = GetMinimaxSigmaD0(); // mode 2 - minimax sigma
622 //Bo: Double_t dNorm = TMath::Min(fDist2/sigmaD,50.);
623 Double_t dNorm = TMath::Min(fDcaV0Daughters/sigmaD,50.);//Bo:
624 //normalized point angle, restricted - because of overflow problems in Exp
625 Double_t likelihood = 0;
628 likelihood = TMath::Exp(-2.*dNorm);
632 likelihood = (TMath::Exp(-2.*dNorm)+0.5* TMath::Exp(-dNorm))/1.5;
636 likelihood = (TMath::Exp(-2.*dNorm)+0.5* TMath::Exp(-dNorm)+0.25*TMath::Exp(-0.5*dNorm))/1.75;
644 Double_t AliESDv0::GetLikelihoodC(Int_t mode0, Int_t /*mode1*/){
646 // get likelihood for Causality
647 // !!! Causality variables defined in AliITStrackerMI !!!
648 // when more information was available
650 Double_t likelihood = 0.5;
651 Double_t minCausal = TMath::Min(fCausality[0],fCausality[1]);
652 Double_t maxCausal = TMath::Max(fCausality[0],fCausality[1]);
653 // minCausal = TMath::Max(minCausal,0.5*maxCausal);
654 //compv0->fTree->SetAlias("LCausal","(1.05-(2*(0.8-exp(-max(RC.fV0rec.fCausality[0],RC.fV0rec.fCausality[1])))+2*(0.8-exp(-min(RC.fV0rec.fCausality[0],RC.fV0rec.fCausality[1]))))/2)**4");
659 likelihood = TMath::Power((1.05-2*(0.8-TMath::Exp(-maxCausal))),4.);
662 likelihood = TMath::Power(1.05-(2*(0.8-TMath::Exp(-maxCausal))+(2*(0.8-TMath::Exp(-minCausal))))*0.5,4.);
669 void AliESDv0::SetCausality(Float_t pb0, Float_t pb1, Float_t pa0, Float_t pa1)
674 fCausality[0] = pb0; // probability - track 0 exist before vertex
675 fCausality[1] = pb1; // probability - track 1 exist before vertex
676 fCausality[2] = pa0; // probability - track 0 exist close after vertex
677 fCausality[3] = pa1; // probability - track 1 exist close after vertex
679 void AliESDv0::SetClusters(Int_t *clp, Int_t *clm)
682 // Set its clusters indexes
684 for (Int_t i=0;i<6;i++) fClusters[0][i] = clp[i];
685 for (Int_t i=0;i<6;i++) fClusters[1][i] = clm[i];
688 Float_t AliESDv0::GetEffMass(UInt_t p1, UInt_t p2){
690 // calculate effective mass
692 const Float_t kpmass[5] = {5.10000000000000037e-04,1.05660000000000004e-01,1.39570000000000000e-01,
693 4.93599999999999983e-01, 9.38270000000000048e-01};
696 Float_t mass1 = kpmass[p1];
697 Float_t mass2 = kpmass[p2];
698 Double_t *m1 = fPmom;
699 Double_t *m2 = fNmom;
701 //if (fRP[p1]+fRM[p2]<fRP[p2]+fRM[p1]){
706 Float_t e1 = TMath::Sqrt(mass1*mass1+
710 Float_t e2 = TMath::Sqrt(mass2*mass2+
715 (m2[0]+m1[0])*(m2[0]+m1[0])+
716 (m2[1]+m1[1])*(m2[1]+m1[1])+
717 (m2[2]+m1[2])*(m2[2]+m1[2]);
719 mass = TMath::Sqrt((e1+e2)*(e1+e2)-mass);