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Checks of the R04 Data Quality. Jin Yi. outline. Survey of R04 Data quality check of R04 Conclusion. BES Annual Meeting JieXiu, Shanxi. May 25, 2004. Survey of R04. The main goals of 2004 data taking are precise R measurement and QCD studying. Data taking time is about 64 days.
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Checks of the R04 Data Quality Jin Yi outline • Survey of R04 • Data quality check of R04 • Conclusion BES Annual Meeting JieXiu, Shanxi May 25, 2004
Survey of R04 • The main goals of 2004 data taking are precise R measurement and QCD studying. • Data taking time is about 64 days. • Data were taken at 3.07, 2.60, 2.20GeV.
Online data stat. VS. offline data stat. 3.07 2.60 2.20 (Hadron Run: 238) (Hadron Run: 361) (Hadron Run: 94) Online Nh = 103563 Nb = 360350 N = 12178 L on = 2788 nb-1 Online Nh = 91255 Nb = 276828 N = 7621 L on = 1305 nb-1 Online Nh = 21634 Nb = 21000 N = 1125 L on = 65 nb-1 VS. VS. VS. Offline Nh =1532 Nb =71641 N =1392 L off = 64 nb-1 Offline Nh = 34934 Nb =1505506 N =15645 L off = 2364 nb-1 Offline Nh = 24900 Nb = 1181177 N = 13318 L off = 1232 nb-1 Note: the data sample for 2.20 is small, so the data quality checks are mostly of 3.07 and 2.60. 5. Data quality checks for reliable physical analysis have been done.
Data Quality Check Contents • BES Global Stability • Subdetector Information • MDC • TOF • BSC • PID • Inclusive decay channels
BES Stability Bhabha events: • momentum-p VS.IIRUN • deposited energy-ESUM VS.IIRUN • dE/dx pulse height-PHMP8 VS.IIRUN • modified dE/dx pulse height-PHMP11VS.IIRUN
3.07 2.60 2.20
Brief Summary for Stability • The distributions of momentum and energy of Bhabha events are fairly flat. • Besides small fluctuations, the distribution of PHMP8 is flat too, and after offline modified, PHMP11 distribution is much flatter. • These figures indicate that MDC and BSC are in good status during data taking.
MDC Information • Track fit quality—MFIT • Vertex resolution • Momentum resolution • dE/dx resolution • θ, Φ distribution
MFIT-3.07 MFIT=2 MFIT=-19 Distribution of vertex of hadronic events on r-Φ,r-z. The data with MFIT -19 won’t be used in physical analysis.
MFIT-2.60 MFIT=2 MFIT=-19 Distribution of track vertex of hadron events on r-Φ,r-z
MFIT-2.20 MFIT=2 MFIT=-19 Distribution of track vertex of hadron events on r-Φ,r-z
MFIT=2 for 3.07, 2.60 (a) PHMP11 VS. p for hadronic events (b) beta VS. p for hadronic events
Vertex resolution-3.07, 2.60 Distribution of Bhabha events vertex on r-Φ,r-z
Momentum resolution-3.07, 2.60 α = 1.5% α = 1.6% (a) Distribution of momenta for Bhabha events (b) momenta VS.Φ (c) momenta resolution VS.Φ
dE/dx resolution-3.07, 2.60 Distribution of PHMP11 for Bhabha events
dE/dx resolution-3.07, 2.60, 2.20 Between 50~70o, there is the offset of χse value. It is because that for the leak currents in layer-7 and 9 of MDC, HV is reduced to 80%. Distribution of χse on Φ
θ, Φ Distribution-3.07 Angular-θ, Φ distribution for Bhabha events normal normal
TOF Information-3.07, 2.60 Fight time VS. Φ The fight time resolution for Bhabha events is about 200ps, and the offset is very limited. ΔT(=Tmea-Texp) VS. Φ
BSC Information-3.07, 2.60 α = 24% α = 24% Distribution of deposited energy of Bhabha events (a) Deposited Energy Measurement VS. Φ for 3.07 (b) Deposited Energy Resolution VS. Φ
Electron-TOF Distribution of Tmea-Texp in different momentum range. The offset is very limited. 0<p<0.25 0.25<p<0.4 0.5<p<0.6 0.4<p<0.5 0.6<p<0.8 0.8<p<1.2
Electron-dE/dx Distribution of χse in different momentum range. The offset is only 0.1. 0<p<0.25 0.25<p<0.4 0.5<p<0.6 0.4<p<0.5 0.6<p<0.8 0.8<p<1.2
K Sample K sample is selected from 2(Kπ). The offsets of TOF and dE/dx are about 0. (b) Momentum distribution of K (a) Invariant mass of Kπ Data sample is pure.
π sample π sample is selected from inclusive K0s. The offsets are very limited.
Inclusive decay channels-K0 total The sample of inclusive K0 at different CM energies (3.07, 2.60, 2.20). fit mass value = 497MeV
Inclusive decay channels-K*0 total The sample of inclusive K*0 at different CM energies (3.07, 2.60, 2.20). fit mass value = 892MeV
Inclusive decay channels-Λ(Λ) The sample of inclusive Λ(Λ) of total. fit mass value= 1115.2MeV
Conclusion for data quality check • As a whole, the detector is in good status during data taking. • We have large data sample at 3.07, 2.60 and 2.20GeV. • The data is of high reliability and quality.