130 likes | 254 Views
YI, Jun-Gyu. K*  K π production in PbPb 160GeV @NA49. Nuclear Physics Lecture III Dec 21, 2006. Heavy Ion Physics Experiment LAB. Contents. about K* K π Procedure Cut conditions dEdx vs logP dEdx vs,each P PID Summary. K*(892)  K π. K*(892) decay modes K π : ~100%
 
                
                E N D
YI, Jun-Gyu K*  Kπ productionin PbPb 160GeV @NA49 Nuclear Physics Lecture III Dec 21, 2006 Heavy Ion Physics Experiment LAB
Contents • about K* Kπ • Procedure • Cut conditions • dEdx vs logP • dEdx vs,each P • PID • Summary YI Jun-Gyu
K*(892)  Kπ • K*(892) decay modes • Kπ : ~100% • K0γ : (2.31±0.20) × 10^-3 % • K±γ: (9.9±0.9) × 10^-4 % • Kππ : < 7 × 10^-4 % • K*(892)± • mass = 891.66 ±0.26 MeV • full width Γ = 50.8 ±0.9 MeV • K*(892)0 • mass = 896.00 ±0.25 MeV • full width Γ = 50.3 ±0.6 MeV YI Jun-Gyu
Procedure • Data Set  01I (“std+-160GeV-central-256TB-01I”) • Set Cut conditions • Event Cut • Track Cut • dE/dx vs. momentum (logP) • dE/dx entry vs. each 1GeV momentums • Fitting Histograms • GetParameters (Constant, Mean, Sigma) • 3 gaussian with 9parameters • Separate K & p with TOF m2 informations • Draw dE/dx vs. m2 • PID • K & p, π, e YI Jun-Gyu
Set Cut conditions • Event Cut • SetVertexX(-1,1) • SetVertexY(-1,1) • SetVertexZ(-582,-580) • Track Cut • SetBx(-4,4) • SetBy(-2,2) • SetP(3,100) YI Jun-Gyu
dE/dx vs. logP • dE/dx vs logP scan each P YI Jun-Gyu
dE/dx vs. logP • dE/dx vs logP – all positive particles scan each P YI Jun-Gyu
0~1 29~30 dE/dx vs. each P YI Jun-Gyu
Fitting Histogram //Macros g1  newTF1(“m1”,”gaus”,min,max); g2  newTF1(“m1”,”gaus”,min,max); g3  newTF1(“m1”,”gaus”,min,max); dEdx_P#  Fit(g1,”R”); dEdx_P#  Fit(g2,”R+”); dEdx_P#  Fit(g3,”R+”); m1GetParamaters(&Par[0]); m2GetParamaters(&Par[0]); m3GetParamaters(&Par[0]); YI Jun-Gyu
Get Parameters //Macros g1  newTF1(“m1”,”gaus”,min,max); g2  newTF1(“m1”,”gaus”,min,max); g3  newTF1(“m1”,”gaus”,min,max); dEdx_P#  Fit(g1,”R”); dEdx_P#  Fit(g2,”R+”); dEdx_P#  Fit(g3,”R+”); m1GetParamaters(&Par[0]); m2GetParamaters(&Par[0]); m3GetParamaters(&Par[0]); YI Jun-Gyu
PID • Separate e,π, p and K • mass^2 informations from TOF • Not yet… YI Jun-Gyu
Summary • Get selected Events from “01I” data set • Get cut parameters from fitting histograms • TO DO • dE/dx vs.m^2  PID • fit Bethe-Bloch • Event MIX for B.G • Goal : mass_inv. spectrum YI Jun-Gyu