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 *
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12 * about the suitability of this software for any purpose. It is *
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14 **************************************************************************/
18 //-------------------------------------------------------------------------
20 // Implementation of the ESD V0MI vertex class
21 // This class is part of the Event Data Summary
22 // set of classes and contains information about
23 // V0 kind vertexes generated by a neutral particle
24 // Numerical part - AliHelix functionality used
26 // Likelihoods for Point angle, DCA and Causality defined => can be used as cut parameters
29 // Quality information can be used as additional cut variables
31 // Origin: Marian Ivanov marian.ivanov@cern.ch
32 //-------------------------------------------------------------------------
34 #include <Riostream.h>
37 #include "AliESDV0MI.h"
43 AliESDV0MIParams AliESDV0MI::fgkParams;
46 AliESDV0MI::AliESDV0MI() :
69 for (Int_t i=0;i<5;i++){
73 fIndex[0]=fIndex[1]=-1;
74 for (Int_t i=0;i<6;i++){fClusters[0][i]=0; fClusters[1][i]=0;}
75 fNormDCAPrim[0]=fNormDCAPrim[1]=0;
76 for (Int_t i=0;i<3;i++){fPP[i]=fPM[i]=fXr[i]=fAngle[i]=0;}
77 for (Int_t i=0;i<3;i++){fOrder[i]=0;}
78 for (Int_t i=0;i<4;i++){fCausality[i]=0;}
81 Double_t AliESDV0MI::GetSigmaY(){
83 // return sigmay in y at vertex position using covariance matrix
85 const Double_t * cp = fParamP.GetCovariance();
86 const Double_t * cm = fParamM.GetCovariance();
87 Double_t sigmay = cp[0]+cm[0]+ cp[5]*(fParamP.X()-fRr)*(fParamP.X()-fRr)+ cm[5]*(fParamM.X()-fRr)*(fParamM.X()-fRr);
88 return (sigmay>0) ? TMath::Sqrt(sigmay):100;
91 Double_t AliESDV0MI::GetSigmaZ(){
93 // return sigmay in y at vertex position using covariance matrix
95 const Double_t * cp = fParamP.GetCovariance();
96 const Double_t * cm = fParamM.GetCovariance();
97 Double_t sigmaz = cp[2]+cm[2]+ cp[9]*(fParamP.X()-fRr)*(fParamP.X()-fRr)+ cm[9]*(fParamM.X()-fRr)*(fParamM.X()-fRr);
98 return (sigmaz>0) ? TMath::Sqrt(sigmaz):100;
101 Double_t AliESDV0MI::GetSigmaD0(){
103 // Sigma parameterization using covariance matrix
105 // sigma of distance between two tracks in vertex position
106 // sigma of DCA is proportianal to sigmaD0
107 // factor 2 difference is explained by the fact that the DCA is calculated at the position
108 // where the tracks as closest together ( not exact position of the vertex)
110 const Double_t * cp = fParamP.GetCovariance();
111 const Double_t * cm = fParamM.GetCovariance();
112 Double_t sigmaD0 = cp[0]+cm[0]+cp[2]+cm[2]+fgkParams.fPSigmaOffsetD0*fgkParams.fPSigmaOffsetD0;
113 sigmaD0 += ((fParamP.X()-fRr)*(fParamP.X()-fRr))*(cp[5]+cp[9]);
114 sigmaD0 += ((fParamM.X()-fRr)*(fParamM.X()-fRr))*(cm[5]+cm[9]);
115 return (sigmaD0>0)? TMath::Sqrt(sigmaD0):100;
119 Double_t AliESDV0MI::GetSigmaAP0(){
121 //Sigma parameterization using covariance matrices
123 Double_t prec = TMath::Sqrt((fPM[0]+fPP[0])*(fPM[0]+fPP[0])
124 +(fPM[1]+fPP[1])*(fPM[1]+fPP[1])
125 +(fPM[2]+fPP[2])*(fPM[2]+fPP[2]));
126 Double_t normp = TMath::Sqrt(fPP[0]*fPP[0]+fPP[1]*fPP[1]+fPP[2]*fPP[2])/prec; // fraction of the momenta
127 Double_t normm = TMath::Sqrt(fPM[0]*fPM[0]+fPM[1]*fPM[1]+fPM[2]*fPM[2])/prec;
128 const Double_t * cp = fParamP.GetCovariance();
129 const Double_t * cm = fParamM.GetCovariance();
130 Double_t sigmaAP0 = fgkParams.fPSigmaOffsetAP0*fgkParams.fPSigmaOffsetAP0; // minimal part
131 sigmaAP0 += (cp[5]+cp[9])*(normp*normp)+(cm[5]+cm[9])*(normm*normm); // angular resolution part
132 Double_t sigmaAP1 = GetSigmaD0()/(TMath::Abs(fRr)+0.01); // vertex position part
133 sigmaAP0 += 0.5*sigmaAP1*sigmaAP1;
134 return (sigmaAP0>0)? TMath::Sqrt(sigmaAP0):100;
137 Double_t AliESDV0MI::GetEffectiveSigmaD0(){
139 // minimax - effective Sigma parameterization
140 // p12 effective curvature and v0 radius postion used as parameters
142 Double_t p12 = TMath::Sqrt(fParamP.GetParameter()[4]*fParamP.GetParameter()[4]+
143 fParamM.GetParameter()[4]*fParamM.GetParameter()[4]);
144 Double_t sigmaED0= TMath::Max(TMath::Sqrt(fRr)-fgkParams.fPSigmaRminDE,0.0)*fgkParams.fPSigmaCoefDE*p12*p12;
147 sigmaED0 = TMath::Sqrt(sigmaED0+fgkParams.fPSigmaOffsetDE*fgkParams.fPSigmaOffsetDE);
148 return (sigmaED0<fgkParams.fPSigmaMaxDE) ? sigmaED0: fgkParams.fPSigmaMaxDE;
152 Double_t AliESDV0MI::GetEffectiveSigmaAP0(){
154 // effective Sigma parameterization of point angle resolution
156 Double_t p12 = TMath::Sqrt(fParamP.GetParameter()[4]*fParamP.GetParameter()[4]+
157 fParamM.GetParameter()[4]*fParamM.GetParameter()[4]);
158 Double_t sigmaAPE= fgkParams.fPSigmaBase0APE;
159 sigmaAPE+= fgkParams.fPSigmaR0APE/(fgkParams.fPSigmaR1APE+fRr);
160 sigmaAPE*= (fgkParams.fPSigmaP0APE+fgkParams.fPSigmaP1APE*p12);
161 sigmaAPE = TMath::Min(sigmaAPE,fgkParams.fPSigmaMaxAPE);
166 Double_t AliESDV0MI::GetMinimaxSigmaAP0(){
168 // calculate mini-max effective sigma of point angle resolution
170 //compv0->fTree->SetAlias("SigmaAP2","max(min((SigmaAP0+SigmaAPE0)*0.5,1.5*SigmaAPE0),0.5*SigmaAPE0+0.003)");
171 Double_t effectiveSigma = GetEffectiveSigmaAP0();
172 Double_t sigmaMMAP = 0.5*(GetSigmaAP0()+effectiveSigma);
173 sigmaMMAP = TMath::Min(sigmaMMAP, fgkParams.fPMaxFractionAP0*effectiveSigma);
174 sigmaMMAP = TMath::Max(sigmaMMAP, fgkParams.fPMinFractionAP0*effectiveSigma+fgkParams.fPMinAP0);
177 Double_t AliESDV0MI::GetMinimaxSigmaD0(){
179 // calculate mini-max sigma of dca resolution
181 //compv0->fTree->SetAlias("SigmaD2","max(min((SigmaD0+SigmaDE0)*0.5,1.5*SigmaDE0),0.5*SigmaDE0)");
182 Double_t effectiveSigma = GetEffectiveSigmaD0();
183 Double_t sigmaMMD0 = 0.5*(GetSigmaD0()+effectiveSigma);
184 sigmaMMD0 = TMath::Min(sigmaMMD0, fgkParams.fPMaxFractionD0*effectiveSigma);
185 sigmaMMD0 = TMath::Max(sigmaMMD0, fgkParams.fPMinFractionD0*effectiveSigma+fgkParams.fPMinD0);
190 Double_t AliESDV0MI::GetLikelihoodAP(Int_t mode0, Int_t mode1){
192 // get likelihood for point angle
194 Double_t sigmaAP = 0.007; //default sigma
197 sigmaAP = GetSigmaAP0(); // mode 0 - covariance matrix estimates used
200 sigmaAP = GetEffectiveSigmaAP0(); // mode 1 - effective sigma used
203 sigmaAP = GetMinimaxSigmaAP0(); // mode 2 - minimax sigma
206 Double_t apNorm = TMath::Min(TMath::ACos(fPointAngle)/sigmaAP,50.);
207 //normalized point angle, restricted - because of overflow problems in Exp
208 Double_t likelihood = 0;
211 likelihood = TMath::Exp(-0.5*apNorm*apNorm);
215 likelihood = (TMath::Exp(-0.5*apNorm*apNorm)+0.5* TMath::Exp(-0.25*apNorm*apNorm))/1.5;
219 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;
226 Double_t AliESDV0MI::GetLikelihoodD(Int_t mode0, Int_t mode1){
228 // get likelihood for DCA
230 Double_t sigmaD = 0.03; //default sigma
233 sigmaD = GetSigmaD0(); // mode 0 - covariance matrix estimates used
236 sigmaD = GetEffectiveSigmaD0(); // mode 1 - effective sigma used
239 sigmaD = GetMinimaxSigmaD0(); // mode 2 - minimax sigma
242 Double_t dNorm = TMath::Min(fDist2/sigmaD,50.);
243 //normalized point angle, restricted - because of overflow problems in Exp
244 Double_t likelihood = 0;
247 likelihood = TMath::Exp(-2.*dNorm);
251 likelihood = (TMath::Exp(-2.*dNorm)+0.5* TMath::Exp(-dNorm))/1.5;
255 likelihood = (TMath::Exp(-2.*dNorm)+0.5* TMath::Exp(-dNorm)+0.25*TMath::Exp(-0.5*dNorm))/1.75;
263 Double_t AliESDV0MI::GetLikelihoodC(Int_t mode0, Int_t /*mode1*/){
265 // get likelihood for Causality
266 // !!! Causality variables defined in AliITStrackerMI !!!
267 // when more information was available
269 Double_t likelihood = 0.5;
270 Double_t minCausal = TMath::Min(fCausality[0],fCausality[1]);
271 Double_t maxCausal = TMath::Max(fCausality[0],fCausality[1]);
272 // minCausal = TMath::Max(minCausal,0.5*maxCausal);
273 //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");
278 likelihood = TMath::Power((1.05-2*(0.8-TMath::Exp(-maxCausal))),4.);
281 likelihood = TMath::Power(1.05-(2*(0.8-TMath::Exp(-maxCausal))+(2*(0.8-TMath::Exp(-minCausal))))*0.5,4.);
288 void AliESDV0MI::SetCausality(Float_t pb0, Float_t pb1, Float_t pa0, Float_t pa1)
293 fCausality[0] = pb0; // probability - track 0 exist before vertex
294 fCausality[1] = pb1; // probability - track 1 exist before vertex
295 fCausality[2] = pa0; // probability - track 0 exist close after vertex
296 fCausality[3] = pa1; // probability - track 1 exist close after vertex
298 void AliESDV0MI::SetClusters(Int_t *clp, Int_t *clm)
301 // Set its clusters indexes
303 for (Int_t i=0;i<6;i++) fClusters[0][i] = clp[i];
304 for (Int_t i=0;i<6;i++) fClusters[1][i] = clm[i];
308 void AliESDV0MI::SetP(const AliExternalTrackParam & paramp) {
315 void AliESDV0MI::SetM(const AliExternalTrackParam & paramm){
322 void AliESDV0MI::SetRp(const Double_t *rp){
326 for (Int_t i=0;i<5;i++) fRP[i]=rp[i];
329 void AliESDV0MI::SetRm(const Double_t *rm){
333 for (Int_t i=0;i<5;i++) fRM[i]=rm[i];
337 void AliESDV0MI::UpdatePID(Double_t pidp[5], Double_t pidm[5])
345 for (Int_t i=0;i<5;i++){
351 for (Int_t i=0;i<5;i++){
357 Float_t AliESDV0MI::GetProb(UInt_t p1, UInt_t p2){
362 return TMath::Max(fRP[p1]+fRM[p2], fRP[p2]+fRM[p1]);
365 Float_t AliESDV0MI::GetEffMass(UInt_t p1, UInt_t p2){
367 // calculate effective mass
369 const Float_t kpmass[5] = {5.10000000000000037e-04,1.05660000000000004e-01,1.39570000000000000e-01,
370 4.93599999999999983e-01, 9.38270000000000048e-01};
373 Float_t mass1 = kpmass[p1];
374 Float_t mass2 = kpmass[p2];
378 //if (fRP[p1]+fRM[p2]<fRP[p2]+fRM[p1]){
383 Float_t e1 = TMath::Sqrt(mass1*mass1+
387 Float_t e2 = TMath::Sqrt(mass2*mass2+
392 (m2[0]+m1[0])*(m2[0]+m1[0])+
393 (m2[1]+m1[1])*(m2[1]+m1[1])+
394 (m2[2]+m1[2])*(m2[2]+m1[2]);
396 mass = TMath::Sqrt((e1+e2)*(e1+e2)-mass);
400 void AliESDV0MI::Update(Float_t vertex[3])
405 // Float_t distance1,distance2;
408 AliHelix phelix(fParamP);
409 AliHelix mhelix(fParamM);
411 //find intersection linear
413 Double_t phase[2][2],radius[2];
414 Int_t points = phelix.GetRPHIintersections(mhelix, phase, radius,200);
415 Double_t delta1=10000,delta2=10000;
417 if (points<=0) return;
419 phelix.LinearDCA(mhelix,phase[0][0],phase[0][1],radius[0],delta1);
420 phelix.LinearDCA(mhelix,phase[0][0],phase[0][1],radius[0],delta1);
421 phelix.LinearDCA(mhelix,phase[0][0],phase[0][1],radius[0],delta1);
424 phelix.LinearDCA(mhelix,phase[1][0],phase[1][1],radius[1],delta2);
425 phelix.LinearDCA(mhelix,phase[1][0],phase[1][1],radius[1],delta2);
426 phelix.LinearDCA(mhelix,phase[1][0],phase[1][1],radius[1],delta2);
428 distance1 = TMath::Min(delta1,delta2);
431 //find intersection parabolic
433 points = phelix.GetRPHIintersections(mhelix, phase, radius);
434 delta1=10000,delta2=10000;
435 Double_t d1=1000.,d2=10000.;
436 Double_t err[3],angles[3];
437 if (points<=0) return;
439 phelix.ParabolicDCA(mhelix,phase[0][0],phase[0][1],radius[0],delta1);
440 phelix.ParabolicDCA(mhelix,phase[0][0],phase[0][1],radius[0],delta1);
441 if (TMath::Abs(fParamP.X()-TMath::Sqrt(radius[0])<3) && TMath::Abs(fParamM.X()-TMath::Sqrt(radius[0])<3)){
442 // if we are close to vertex use error parama
444 err[1] = fParamP.GetCovariance()[0]+fParamM.GetCovariance()[0]+0.05*0.05
445 +0.3*(fParamP.GetCovariance()[2]+fParamM.GetCovariance()[2]);
446 err[2] = fParamP.GetCovariance()[2]+fParamM.GetCovariance()[2]+0.05*0.05
447 +0.3*(fParamP.GetCovariance()[0]+fParamM.GetCovariance()[0]);
449 phelix.GetAngle(phase[0][0],mhelix,phase[0][1],angles);
450 Double_t tfi = TMath::Abs(TMath::Tan(angles[0]));
451 Double_t tlam = TMath::Abs(TMath::Tan(angles[1]));
452 err[0] = err[1]/((0.2+tfi)*(0.2+tfi))+err[2]/((0.2+tlam)*(0.2+tlam));
453 err[0] = ((err[1]*err[2]/((0.2+tfi)*(0.2+tfi)*(0.2+tlam)*(0.2+tlam))))/err[0];
454 phelix.ParabolicDCA2(mhelix,phase[0][0],phase[0][1],radius[0],delta1,err);
456 Double_t xd[3],xm[3];
457 phelix.Evaluate(phase[0][0],xd);
458 mhelix.Evaluate(phase[0][1],xm);
459 d1 = (xd[0]-xm[0])*(xd[0]-xm[0])+(xd[1]-xm[1])*(xd[1]-xm[1])+(xd[2]-xm[2])*(xd[2]-xm[2]);
462 phelix.ParabolicDCA(mhelix,phase[1][0],phase[1][1],radius[1],delta2);
463 phelix.ParabolicDCA(mhelix,phase[1][0],phase[1][1],radius[1],delta2);
464 if (TMath::Abs(fParamP.X()-TMath::Sqrt(radius[1])<3) && TMath::Abs(fParamM.X()-TMath::Sqrt(radius[1])<3)){
465 // if we are close to vertex use error paramatrization
467 err[1] = fParamP.GetCovariance()[0]+fParamM.GetCovariance()[0]+0.05*0.05
468 +0.3*(fParamP.GetCovariance()[2]+fParamM.GetCovariance()[2]);
469 err[2] = fParamP.GetCovariance()[2]+fParamM.GetCovariance()[2]+0.05*0.05
470 +0.3*(fParamP.GetCovariance()[0]+fParamM.GetCovariance()[0]);
472 phelix.GetAngle(phase[1][0],mhelix,phase[1][1],angles);
473 Double_t tfi = TMath::Abs(TMath::Tan(angles[0]));
474 Double_t tlam = TMath::Abs(TMath::Tan(angles[1]));
475 err[0] = err[1]/((0.2+tfi)*(0.2+tfi))+err[2]/((0.2+tlam)*(0.2+tlam));
476 err[0] = ((err[1]*err[2]/((0.2+tfi)*(0.2+tfi)*(0.2+tlam)*(0.2+tlam))))/err[0];
477 phelix.ParabolicDCA2(mhelix,phase[1][0],phase[1][1],radius[1],delta2,err);
479 Double_t xd[3],xm[3];
480 phelix.Evaluate(phase[1][0],xd);
481 mhelix.Evaluate(phase[1][1],xm);
482 d2 = (xd[0]-xm[0])*(xd[0]-xm[0])+(xd[1]-xm[1])*(xd[1]-xm[1])+(xd[2]-xm[2])*(xd[2]-xm[2]);
485 distance2 = TMath::Min(delta1,delta2);
488 Double_t xd[3],xm[3];
489 phelix.Evaluate(phase[0][0],xd);
490 mhelix.Evaluate(phase[0][1], xm);
491 fXr[0] = 0.5*(xd[0]+xm[0]);
492 fXr[1] = 0.5*(xd[1]+xm[1]);
493 fXr[2] = 0.5*(xd[2]+xm[2]);
495 Float_t wy = fParamP.GetCovariance()[0]/(fParamP.GetCovariance()[0]+fParamM.GetCovariance()[0]);
496 Float_t wz = fParamP.GetCovariance()[2]/(fParamP.GetCovariance()[2]+fParamM.GetCovariance()[2]);
497 fXr[0] = 0.5*( (1.-wy)*xd[0]+ wy*xm[0] + (1.-wz)*xd[0]+ wz*xm[0] );
498 fXr[1] = (1.-wy)*xd[1]+ wy*xm[1];
499 fXr[2] = (1.-wz)*xd[2]+ wz*xm[2];
501 phelix.GetMomentum(phase[0][0],fPP);
502 mhelix.GetMomentum(phase[0][1],fPM);
503 phelix.GetAngle(phase[0][0],mhelix,phase[0][1],fAngle);
504 fRr = TMath::Sqrt(fXr[0]*fXr[0]+fXr[1]*fXr[1]);
507 Double_t xd[3],xm[3];
508 phelix.Evaluate(phase[1][0],xd);
509 mhelix.Evaluate(phase[1][1], xm);
510 fXr[0] = 0.5*(xd[0]+xm[0]);
511 fXr[1] = 0.5*(xd[1]+xm[1]);
512 fXr[2] = 0.5*(xd[2]+xm[2]);
513 Float_t wy = fParamP.GetCovariance()[0]/(fParamP.GetCovariance()[0]+fParamM.GetCovariance()[0]);
514 Float_t wz = fParamP.GetCovariance()[2]/(fParamP.GetCovariance()[2]+fParamM.GetCovariance()[2]);
515 fXr[0] = 0.5*( (1.-wy)*xd[0]+ wy*xm[0] + (1.-wz)*xd[0]+ wz*xm[0] );
516 fXr[1] = (1.-wy)*xd[1]+ wy*xm[1];
517 fXr[2] = (1.-wz)*xd[2]+ wz*xm[2];
519 phelix.GetMomentum(phase[1][0], fPP);
520 mhelix.GetMomentum(phase[1][1], fPM);
521 phelix.GetAngle(phase[1][0],mhelix,phase[1][1],fAngle);
522 fRr = TMath::Sqrt(fXr[0]*fXr[0]+fXr[1]*fXr[1]);
524 fDist1 = TMath::Sqrt(TMath::Min(d1,d2));
525 fDist2 = TMath::Sqrt(distance2);
528 Double_t v[3] = {fXr[0]-vertex[0],fXr[1]-vertex[1],fXr[2]-vertex[2]};
529 Double_t p[3] = {fPP[0]+fPM[0], fPP[1]+fPM[1],fPP[2]+fPM[2]};
530 Double_t vnorm2 = v[0]*v[0]+v[1]*v[1];
531 if (TMath::Abs(v[2])>100000) return;
532 Double_t vnorm3 = TMath::Sqrt(TMath::Abs(v[2]*v[2]+vnorm2));
533 vnorm2 = TMath::Sqrt(vnorm2);
534 Double_t pnorm2 = p[0]*p[0]+p[1]*p[1];
535 Double_t pnorm3 = TMath::Sqrt(p[2]*p[2]+pnorm2);
536 pnorm2 = TMath::Sqrt(pnorm2);
537 fPointAngleFi = (v[0]*p[0]+v[1]*p[1])/(vnorm2*pnorm2);
538 fPointAngleTh = (v[2]*p[2]+vnorm2*pnorm2)/(vnorm3*pnorm3);
539 fPointAngle = (v[0]*p[0]+v[1]*p[1]+v[2]*p[2])/(vnorm3*pnorm3);