// position of the cascade decay
fPos[0]=0.5*(x1+xm); fPos[1]=0.5*(y1+ym); fPos[2]=0.5*(z1+zm);
-
-
- // momenta of the bachelor and the V0
-
- fBachMom[0]=px1; fBachMom[1]=py1; fBachMom[2]=pz1;
- fV0mom[0]=px2; fV0mom[1]=py2; fV0mom[2]=pz2;
-
+
+
// invariant mass of the cascade (default is Ximinus)
Double_t e1=TMath::Sqrt(0.13957*0.13957 + px1*px1 + py1*py1 + pz1*pz1);
fEffMass=TMath::Sqrt((e1+e2)*(e1+e2)-
(px1+px2)*(px1+px2)-(py1+py2)*(py1+py2)-(pz1+pz2)*(pz1+pz2));
+
+ // momenta of the bachelor and the V0
+
+ fBachMom[0]=px1; fBachMom[1]=py1; fBachMom[2]=pz1;
+ v.GetNPxPyPz(px2,py2,pz2);
+ fV0mom[0][0]=px2; fV0mom[0][1]=py2; fV0mom[0][2]=pz2;
+ v.GetPPxPyPz(px2,py2,pz2);
+ fV0mom[1][0]=px2; fV0mom[1][1]=py2; fV0mom[1][2]=pz2;
+
+
fChi2=7.;
}
-void AliCascadeVertex::ChangeMassHypothesis(Int_t code) {
+/*
+Double_t AliCascadeVertex::ChangeMassHypothesis(Double_t &v0q, Int_t code) {
//--------------------------------------------------------------------
// This function changes the mass hypothesis for this cascade
+ // and returns the "kinematical quality" of this hypothesis
+ // together with the "quality" of associated V0 (argument v0q)
//--------------------------------------------------------------------
-
- // HOW TO DISTINGUISH BETWEEN A XIMINUS AND A XIPLUS ??????????
- // SAME QUESTION FOR (ANTI-)OMEGA'S (here) ... AND FOR (ANTI-)LAMBDAS (in AliV0vertex) ??
- // -> NEED ADDITIONAL CONDITION ON BACHELOR AND V0 PDGCODE !!!! BUT in the ANALYSIS MACROS !!!
-
- Double_t massBach, massV0;
+ Double_t nmass=0.13957, pmass=0.93827, des0=0.9437-0.1723;
+ Double_t bmass=0.13957, mass =1.3213, des =1.1243-0.1970;
- switch (code) {
+ fPdgCode=code;
+ switch (code) {
+ case 213:
+ bmass=0.93827;
+ break;
case kXiMinus:
- massBach=0.13957; massV0=1.11568; break;
+ break;
case kXiPlusBar:
- massBach=0.13957; massV0=1.11568; break;
+ nmass=0.93827; pmass=0.13957; des0=-des0;
+ des=-des;
+ break;
case kOmegaMinus:
- massBach=0.49368; massV0=1.11568; break;
+ bmass=0.49368; mass=1.67245; des=1.1355-0.5369;
+ break;
case kOmegaPlusBar:
- massBach=0.49368; massV0=1.11568; break;
-
+ nmass=0.93827; pmass=0.13957; des0=-des0;
+ bmass=0.49368; mass=1.67245; des=0.5369-1.1355;
+ break;
default:
- cerr<<"AliCascadeVertex::ChangeMassHypothesis: ";
- cerr<<"invalide PDG code ! Assuming XiMinus's...\n";
- massBach=0.13957; massV0=1.11568; break;
+ cerr<<"AliCascadeVertex::ChangeMassHypothesis: ";
+ cerr<<"Invalide PDG code ! Assuming XiMinus's...\n";
+ fPdgCode=kXiMinus;
+ break;
}
- Double_t px1=fBachMom[0], py1=fBachMom[1], pz1=fBachMom[2];
- Double_t px2=fV0mom[0], py2=fV0mom[1], pz2=fV0mom[2];
+ Double_t pxn=fV0mom[0][0], pyn=fV0mom[0][1], pzn=fV0mom[0][2];
+ Double_t pxp=fV0mom[1][0], pyp=fV0mom[1][1], pzp=fV0mom[1][2];
+ Double_t en=TMath::Sqrt(nmass*nmass + pxn*pxn + pyn*pyn + pzn*pzn);
+ Double_t ep=TMath::Sqrt(pmass*pmass + pxp*pxp + pyp*pyp + pzp*pzp);
+ Double_t px0=pxn+pxp, py0=pyn+pyp, pz0=pzn+pzp;
+ Double_t p0=TMath::Sqrt(px0*px0 + py0*py0 + pz0*pz0);
- Double_t e1=TMath::Sqrt(massBach*massBach + px1*px1 + py1*py1 + pz1*pz1);
- Double_t e2=TMath::Sqrt(massV0*massV0 + px2*px2 + py2*py2 + pz2*pz2);
- fEffMass=TMath::Sqrt((e1+e2)*(e1+e2)-
- (px1+px2)*(px1+px2)-(py1+py2)*(py1+py2)-(pz1+pz2)*(pz1+pz2));
+ Double_t gamma0=(en+ep)/1.11568, betagamma0=p0/1.11568;
+ Double_t pln=(pxn*px0 + pyn*py0 + pzn*pz0)/p0;
+ Double_t plp=(pxp*px0 + pyp*py0 + pzp*pz0)/p0;
+ Double_t plps=gamma0*plp - betagamma0*ep;
+
+ Double_t diff0=2*gamma0*plps + betagamma0*des0;
+
+
+ v0q=plp-pln-diff0;
+
+
+ Double_t pxb=fBachMom[0], pyb=fBachMom[1], pzb=fBachMom[2];
+
+ Double_t e0=TMath::Sqrt(1.11568*1.11568 + p0*p0);
+ Double_t eb=TMath::Sqrt(bmass*bmass + pxb*pxb + pyb*pyb + pzb*pzb);
+ Double_t pxl=px0+pxb, pyl=py0+pyb, pzl=pz0+pzb;
+ Double_t pl=TMath::Sqrt(pxl*pxl + pyl*pyl + pzl*pzl);
+ fEffMass=TMath::Sqrt((e0+eb)*(e0+eb) - pl*pl);
+
+ Double_t gamma=(e0+eb)/mass, betagamma=pl/mass;
+ Double_t pl0=(px0*pxl + py0*pyl + pz0*pzl)/pl;
+ Double_t plb=(pxb*pxl + pyb*pyl + pzb*pzl)/pl;
+ Double_t pl0s=gamma*pl0 - betagamma*e0;
+
+ Double_t diff=2*gamma*pl0s + betagamma*des;
+
+ return (pl0-plb-diff);
+}
+*/
+
+Double_t AliCascadeVertex::ChangeMassHypothesis(Double_t &v0q, Int_t code) {
+ //--------------------------------------------------------------------
+ // This function changes the mass hypothesis for this cascade
+ // and returns the "kinematical quality" of this hypothesis
+ // together with the "quality" of associated V0 (argument v0q)
+ //--------------------------------------------------------------------
+ Double_t nmass=0.13957, pmass=0.93827, ps0=0.101;
+ Double_t bmass=0.13957, mass =1.3213, ps =0.139;
+
fPdgCode=code;
+
+ switch (code) {
+ case 213:
+ bmass=0.93827;
+ break;
+ case kXiMinus:
+ break;
+ case kXiPlusBar:
+ nmass=0.93827; pmass=0.13957;
+ break;
+ case kOmegaMinus:
+ bmass=0.49368; mass=1.67245; ps=0.211;
+ break;
+ case kOmegaPlusBar:
+ nmass=0.93827; pmass=0.13957;
+ bmass=0.49368; mass=1.67245; ps=0.211;
+ break;
+ default:
+ cerr<<"AliCascadeVertex::ChangeMassHypothesis: ";
+ cerr<<"Invalide PDG code ! Assuming XiMinus's...\n";
+ fPdgCode=kXiMinus;
+ break;
+ }
+
+ Double_t pxn=fV0mom[0][0], pyn=fV0mom[0][1], pzn=fV0mom[0][2];
+ Double_t pxp=fV0mom[1][0], pyp=fV0mom[1][1], pzp=fV0mom[1][2];
+ Double_t px0=pxn+pxp, py0=pyn+pyp, pz0=pzn+pzp;
+ Double_t p0=TMath::Sqrt(px0*px0 + py0*py0 + pz0*pz0);
+
+ Double_t e0=TMath::Sqrt(1.11568*1.11568 + p0*p0);
+ Double_t beta0=p0/e0;
+ Double_t pln=(pxn*px0 + pyn*py0 + pzn*pz0)/p0;
+ Double_t plp=(pxp*px0 + pyp*py0 + pzp*pz0)/p0;
+ Double_t pt2=pxp*pxp + pyp*pyp + pzp*pzp - plp*plp;
+
+ Double_t a=(plp-pln)/(plp+pln);
+ a -= (pmass*pmass-nmass*nmass)/(1.11568*1.11568);
+ a = 0.25*beta0*beta0*1.11568*1.11568*a*a + pt2;
+
+
+ v0q=a - ps0*ps0;
+
+
+ Double_t pxb=fBachMom[0], pyb=fBachMom[1], pzb=fBachMom[2];
+
+ Double_t eb=TMath::Sqrt(bmass*bmass + pxb*pxb + pyb*pyb + pzb*pzb);
+ Double_t pxl=px0+pxb, pyl=py0+pyb, pzl=pz0+pzb;
+ Double_t pl=TMath::Sqrt(pxl*pxl + pyl*pyl + pzl*pzl);
+
+ fEffMass=TMath::Sqrt((e0+eb)*(e0+eb) - pl*pl);
+
+ Double_t beta=pl/(e0+eb);
+ Double_t pl0=(px0*pxl + py0*pyl + pz0*pzl)/pl;
+ Double_t plb=(pxb*pxl + pyb*pyl + pzb*pzl)/pl;
+ pt2=p0*p0 - pl0*pl0;
+
+ a=(pl0-plb)/(pl0+plb);
+ a -= (1.11568*1.11568-bmass*bmass)/(mass*mass);
+ a = 0.25*beta*beta*mass*mass*a*a + pt2;
+
+ return (a - ps*ps);
}
void
//--------------------------------------------------------------------
// This function returns the cascade momentum (global)
//--------------------------------------------------------------------
- px=fV0mom[0]+fBachMom[0];
- py=fV0mom[1]+fBachMom[1];
- pz=fV0mom[2]+fBachMom[2];
+ px=fV0mom[0][0]+fV0mom[1][0]+fBachMom[0];
+ py=fV0mom[0][1]+fV0mom[1][1]+fBachMom[1];
+ pz=fV0mom[0][2]+fV0mom[1][2]+fBachMom[2];
}
void AliCascadeVertex::GetXYZ(Double_t &x, Double_t &y, Double_t &z) const {
//--------------------------------------------------------------------
Double_t x=fPos[0],y=fPos[1],z=fPos[2];
- Double_t px=fV0mom[0]+fBachMom[0];
- Double_t py=fV0mom[1]+fBachMom[1];
- Double_t pz=fV0mom[2]+fBachMom[2];
+ Double_t px=fV0mom[0][0]+fV0mom[1][0]+fBachMom[0];
+ Double_t py=fV0mom[0][1]+fV0mom[1][1]+fBachMom[1];
+ Double_t pz=fV0mom[0][2]+fV0mom[1][2]+fBachMom[2];
Double_t dx=(y0-y)*pz - (z0-z)*py;
Double_t dy=(x0-x)*pz - (z0-z)*px;
return d;
}
+
git://git.uio.no / u / mrichter / AliRoot.git / blobdiff