From 88f467170a5523f3065c1c04d2b571f21f03be99 Mon Sep 17 00:00:00 2001 From: belikov Date: Fri, 24 Jun 2011 14:08:55 +0000 Subject: [PATCH] New BB parameterizations for low momentum electrons. Improved BB parameterization for IT standone pions, kaons, protons. Updated dE/dx resolution value for tracks with only 2 ITS clusters in SDD+SSD (F. Prino and L. Milano). --- STEER/AliITSPIDResponse.cxx | 54 ++++++++++++++++++++++++------------- STEER/AliITSPIDResponse.h | 6 ++++- 2 files changed, 40 insertions(+), 20 deletions(-) diff --git a/STEER/AliITSPIDResponse.cxx b/STEER/AliITSPIDResponse.cxx index e45563c0845..faf8a5f2a75 100644 --- a/STEER/AliITSPIDResponse.cxx +++ b/STEER/AliITSPIDResponse.cxx @@ -42,15 +42,20 @@ AliITSPIDResponse::AliITSPIDResponse(Bool_t isMC): fBBtpcits[2]=0.905; fBBtpcits[3]=1.2; fBBtpcits[4]=6.6; - fBBsa[0]=5.33458E4; - fBBsa[1]=16.5303; - fBBsa[2]=2.60065E-3; - fBBsa[3]=3.59533E-4; - fBBsa[4]=7.51168E-5; + fBBsa[0]=2.73198E7; + fBBsa[1]=6.92389; + fBBsa[2]=1.90088E-6; + fBBsa[3]=1.90088E-6; + fBBsa[4]=3.40644E-7; + fBBsaElectron[0]=4.05799E6; + fBBsaElectron[1]=38.5713; + fBBsaElectron[2]=1.46462E-7; + fBBsaElectron[3]=1.46462E-7; + fBBsaElectron[4]=4.40284E-7; fResolSA[0]=1.; // 0 cluster tracks should not be used - fResolSA[1]=0.25; // rough values for tracks with 1 or 2 - fResolSA[2]=0.2; // clusters (not to be used) - fResolSA[3]=0.116; // value from pp 2010 run (L. Milano, 18-Jan-11) + fResolSA[1]=0.25; // rough values for tracks with 1 + fResolSA[2]=0.131; // value from pp 2010 run (L. Milano, 16-Jun-11) + fResolSA[3]=0.113; // value from pp 2010 run fResolSA[4]=0.104; // value from pp 2010 run for(Int_t i=0; i<5;i++) fResolTPCITS[i]=0.13; }else{ @@ -59,16 +64,21 @@ AliITSPIDResponse::AliITSPIDResponse(Bool_t isMC): fBBtpcits[2]=1.00; fBBtpcits[3]=0.964; fBBtpcits[4]=2.59; - fBBsa[0]=-2.48; - fBBsa[1]=23.13; - fBBsa[2]=1.161; - fBBsa[3]=0.93; - fBBsa[4]=-1.2973; + fBBsa[0]=2.02078E7; + fBBsa[1]=14.0724; + fBBsa[2]=3.84454E-7; + fBBsa[3]=3.84454E-7; + fBBsa[4]=2.43913E-7; + fBBsaElectron[0]=2.26807E6; + fBBsaElectron[1]=99.985; + fBBsaElectron[2]=0.000714841; + fBBsaElectron[3]=0.000259585; + fBBsaElectron[4]=1.39412E-7; fResolSA[0]=1.; // 0 cluster tracks should not be used - fResolSA[1]=0.25; // rough values for tracks with 1 or 2 - fResolSA[2]=0.2; // clusters (not to be used) - fResolSA[3]=0.110; // value from pp 2010 simulations (L. Milano, 18-Jan-11) - fResolSA[4]=0.096; // value from pp 2010 simulations + fResolSA[1]=0.25; // rough values for tracks with 1 + fResolSA[2]=0.126; // value from pp 2010 simulations (L. Milano, 16-Jun-11) + fResolSA[3]=0.109; // value from pp 2010 simulations + fResolSA[4]=0.097; // value from pp 2010 simulations for(Int_t i=0; i<5;i++) fResolTPCITS[i]=0.13; } } @@ -118,7 +128,13 @@ Double_t AliITSPIDResponse::Bethe(Double_t p, Double_t mass, Bool_t isSA) const Double_t gamma=bg/beta; Double_t par[5]; if(isSA){ - for(Int_t ip=0; ip<5;ip++) par[ip]=fBBsa[ip]; + if(mass>0.0005 && mass<0.00052){ + //if is an electron use a specific BB parameterization + //To be used only between 100 and 160 MeV/c + for(Int_t ip=0; ip<5;ip++) par[ip]=fBBsaElectron[ip]; + }else{ + for(Int_t ip=0; ip<5;ip++) par[ip]=fBBsa[ip]; + } }else{ for(Int_t ip=0; ip<5;ip++) par[ip]=fBBtpcits[ip]; } @@ -127,7 +143,7 @@ Double_t AliITSPIDResponse::Bethe(Double_t p, Double_t mass, Bool_t isSA) const eff=(bg-par[3])*(bg-par[3])+par[4]; else eff=(par[2]-par[3])*(par[2]-par[3])+par[4]; - + Double_t bb=0.; if(gamma>=0. && beta>0.){ bb=(par[1]+2.0*TMath::Log(gamma)-beta*beta)*(par[0]/(beta*beta))*eff; diff --git a/STEER/AliITSPIDResponse.h b/STEER/AliITSPIDResponse.h index 556f3f790d7..bd25e84b54f 100644 --- a/STEER/AliITSPIDResponse.h +++ b/STEER/AliITSPIDResponse.h @@ -27,6 +27,9 @@ public: void SetBetheBlochParamsITSsa(Double_t* param){ for(Int_t iPar=0; iPar<5; iPar++) fBBsa[iPar]=param[iPar]; } + void SetElectronBetheBlochParamsITSsa(Double_t* param){ + for(Int_t iPar=0; iPar<5; iPar++) fBBsaElectron[iPar]=param[iPar]; + } Double_t BetheAleph(Double_t p,Double_t mass) const; Double_t Bethe(Double_t p, Double_t mass, Bool_t iSA=kFALSE) const; @@ -49,11 +52,12 @@ private: Double_t fKp4; // ALEPH BB param 4 Double_t fKp5; // ALEPH BB param Double_t fBBsa[5]; // parameters of BB for SA tracks + Double_t fBBsaElectron[5]; // parameters of BB for SA tracks Double_t fBBtpcits[5]; // parameters of BB for TPC+ITS tracks Float_t fResolSA[5]; // resolutions vs. n. of SDD/SSD points Float_t fResolTPCITS[5]; // resolutions vs. n. of SDD/SSD points - ClassDef(AliITSPIDResponse,2) // ITS PID class + ClassDef(AliITSPIDResponse,3) // ITS PID class }; #endif -- 2.43.0