1 #include "AliHBTPair.h"
2 #include "AliHBTParticle.h"
7 /************************************************************************/
8 AliHBTPair::AliHBTPair(Bool_t rev)
10 //value of rev defines if it is Swaped
11 //if you pass kTRUE swpaped pair will NOT be created
12 //though you wont be able to get the swaped pair from this pair
14 if(!rev) fSwapedPair = new AliHBTPair(kTRUE); //if false create swaped pair
15 else fSwapedPair = 0x0; //if true set the pointer to NULL
18 /************************************************************************/
19 Double_t AliHBTPair::GetInvMass()
23 CalculateInvMassSqr(); //method is inline so we not waste th time for jumping into method
25 if(fInvMassSqr<0) fInvMass = TMath::Sqrt(-fInvMassSqr);
26 else fInvMass = TMath::Sqrt(fInvMassSqr);
28 fInvMassNotCalc = kFALSE;
32 /************************************************************************/
33 Double_t AliHBTPair::GetQSideCMSLC()
35 //return Q Side in Central Of Mass System in Longitudialy Comoving Frame
37 if (fQSideCMSLCNotCalc)
39 fQSideCMSLC = (fPart1->Px()*fPart2->Py()-fPart2->Px()*fPart1->Py())/GetKt();
40 fQSideCMSLCNotCalc = kFALSE;
44 /************************************************************************/
45 Double_t AliHBTPair::GetQOutCMSLC()
51 Double_t k2 = fPxSum*fPxDiff+fPySum*fPyDiff;
52 fQOutCMSLC = 0.5*k2/GetKt();
53 fQOutCMSLCNotCalc = kFALSE;
57 /************************************************************************/
58 Double_t AliHBTPair::GetQLongCMSLC()
60 if (fQLongCMSLCNotCalc)
64 Double_t beta = fPzSum/fESum;
65 Double_t gamma = 1.0/TMath::Sqrt(1.0 - beta*beta);
66 fQLongCMSLC = gamma*( fPzDiff - beta*fEDiff );
67 fQLongCMSLCNotCalc = kFALSE;
71 /************************************************************************/
72 Double_t AliHBTPair::GetKt()
77 fKt = 0.5*TMath::Hypot(fPxSum,fPySum);
82 /************************************************************************/
84 Double_t AliHBTPair::GetKStar()
91 Double_t Ptrans = fPxSum*fPxSum + fPySum*fPySum;
92 Double_t Mtrans = fESum*fESum - fPzSum*fPzSum;
93 Double_t Pinv = TMath::Sqrt(Mtrans - Ptrans);
95 Double_t Q = ( fPart1->GetMass()*fPart1->GetMass() - fPart2->GetMass()*fPart2->GetMass())/Pinv;
99 Q = TMath::Sqrt( Q*Q - fQInvL);
101 fKStarNotCalc = kFALSE;
105 /************************************************************************/
107 Double_t AliHBTPair::GetQInv()
113 if (fQInvL < 0.) fQInv = TMath::Sqrt(-fQInvL);
114 else fQInv = -TMath::Sqrt( fQInvL);
116 fQInvNotCalc = kFALSE;