1. Survey of R04 Data quality check of R04 Conclusion Checks of the R04 Data Quality outline Jin Yi May 25, 2004BES Annual Meeting JieXiu, Shanxi

2. Survey of R04 1.The main goals of 2004 data taking are precise R measurement and QCD studying. 2.Data taking time is about 64 days. 3.Data were taken at 3.07, 2.60, 2.20GeV.

3. 4.Online data stat. VS. offline data stat. Online N h = 103563 N b = 360350 N  = 12178 L on = 2788 nb -1 Offline N h = 34934 N b =1505506 N  =15645 L off = 2364 nb -1 Online N h = 91255 N b = 276828 N  = 7621 L on = 1305 nb -1 Offline N h = 24900 N b = 1181177 N  = 13318 L off = 1232 nb -1 Online N h = 21634 N b = 21000 N  = 1125 L on = 65 nb -1 Offline N h =1532 N b =71641 N  =1392 L off = 64 nb -1 VS. 3.07 2.60 2.20 ( Hadron R un: 238) ( Hadron R un: 361) ( Hadron R un: 94) 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.

4. Data Quality Check Contents BES Global Stability Subdetector Information  MDC  TOF  BSC PID Inclusive decay channels

5. 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-PHMP11 VS. IIRUN

6. 3.07 2.60 2.20

7. 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.

8. MDC Information Track fit quality—MFIT Vertex resolution Momentum resolution dE/dx resolution θ, Φ distribution

9. MFIT-3.07 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 MFIT=-19

10. MFIT-2.60 Distribution of track vertex of hadron events on r-Φ, r-z MFIT=2 MFIT=-19

11. MFIT-2.20 Distribution of track vertex of hadron events on r-Φ, r-z MFIT=2 MFIT=-19

12. MFIT=2 for 3.07, 2.60 (a) PHMP11 VS. p for hadronic events (b) beta VS. p for hadronic events

13. Vertex resolution-3.07, 2.60 Distribution of Bhabha events vertex on r-Φ, r-z

14. 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

15. dE/dx resolution-3.07, 2.60 Distribution of PHMP11 for Bhabha events

16. dE/dx resolution-3.07, 2.60, 2.20 Between 50~70 o, there is the offset of χ se value. It is because that for the leak currents in layer-7 and 9 of MDC, HV is reduced to 80%. Distribution of χ se on Φ

17. θ, Φ Distribution-3.07 Angular-θ, Φ distribution for Bhabha events normal

18. TOF Information-3.07, 2.60 The fight time resolution for Bhabha events is about 200ps, and the offset is very limited. Fight time VS. Φ ΔT(=T mea - T exp) VS. Φ

19. BSC Information-3.07, 2.60 (a) Deposited Energy Measurement VS. Φ for 3.07 (b) Deposited Energy Resolution VS. Φ α = 24% Distribution of deposited energy of Bhabha events α = 24%

20. Electron-TOF Distribution of T mea -T exp in different momentum range. The offset is very limited. 0.6<p<0.8 0<p<0.250.25<p<0.4 0.4<p<0.5 0.5<p<0.6 0.8<p<1.2

21. Electron-dE/dx Distribution of χ se in different momentum range. The offset is only 0.1. 0<p<0.250.25<p<0.4 0.4<p<0.5 0.5<p<0.6 0.6<p<0.8 0.8<p<1.2

22. K Sample K sample is selected from 2(Kπ). The offsets of TOF and dE/dx are about 0. Data sample is pure. (b) Momentum distribution of K (a) Invariant mass of Kπ

23. π sample π sample is selected from inclusive K 0 s. The offsets are very limited.

24. Inclusive decay channels-K 0 The sample of inclusive K 0 at different CM energies (3.07, 2.60, 2.20). fit mass value = 497MeV total

25. Inclusive decay channels-K *0 The sample of inclusive K *0 at different CM energies (3.07, 2.60, 2.20). total fit mass value = 892MeV

26. Inclusive decay channels-Λ(Λ) The sample of inclusive Λ(Λ) of total. fit mass value= 1115.2MeV

27. 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.