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HERA-B

HERA-B. Bernhard Schmidt DESY - HH. PRC open session, October 30, 2002. Status of “run 2000” analysis. - nearing completion. . . submitted. in press. Some additional theses ongoing. There are no more data left to analyze. Detector status. . . ITR.

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HERA-B

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  1. HERA-B Bernhard Schmidt DESY - HH PRC open session, October 30, 2002

  2. Status of “run 2000” analysis - nearing completion   submitted in press Some additional theses ongoing There are no more data left to analyze

  3. Detector status  

  4. ITR • HV training completed (425 hours operation), stability ok • HVproblems: 4 (160) chambers in-operational (1 cathode, 3 GEM) acceptable level • Hit efficiency: (90 - 95%) & S/N (16-24) looks ok • Alignment : first iterationdone chambers of MS01 layer

  5. ~25% of channels show no signal ! ITR-2 abnormal chamber normal chamber REASON UNCLEAR • New problem observed recently Run 19990 ITR-tracks at exit of PC section Due to high redundancy in ITR: Coverage and efficiency of trackingstill sufficient Worrisome but not fatal

  6. OTR • Fully operational in trigger and for tracking • HV problems level out : mean time between failures at 58 h (since May 2002) • Noise level improved considerably threshold, noise at 1% Channel statistics (-) (+) Cell efficiency >95 %,fine for triggering and tracking

  7. 0  Calibration precision ECAL 1 % • Fully operational and calibrated with  (1%) • Dramatically improved performance compared to 2000( noise, stability, spatial resolution)

  8. J/ee signals ECAL-2 -1 < E/p < 3 • improved PID with ECAL • no BR tag required to see J/

  9. Muon System • Operational, some non-working chambers in MU1, not critical • No new HV problems since May 2002 • Efficiency of pad read out: on average 88±3 % (include. dead channels), no major holes Not perfect, but sufficient for triggering Muon tracks at MU1 position J/y->µµ online

  10. TRIGGER and DAQ status : FLT • FLT routinely used for J/y triggering now • High level of understanding but still some mysteries • single track efficienciesusable(25% µ-ons, 60% for electrons ) • FLT - pair trigger works

  11. trigger schemes star mode • advantage : • much less affected by FLT efficiency (OR inst. AND) • covers ITR for second track (acceptance at xF> 0) • No FLT-pairs, but FLT(1 track + 1 pre-trigger) & SLT(2tracks) achieved J/ rates: 400 J/ per hour and MHz interaction rate (e+µ) ? Dead time, achievable interaction rate ? > 800 J/ per hour Typical : 30 % DT at 3 MHz Seen : 0% DT at 3 MHz -> ? work ongoing beam & DAQ conditions We hope to get ~ 1000 J/ per hour these days.

  12. Status of Commissioning 20 % running in 2002 so far 70 % Many thanks to HERA for giving us beam in hard times

  13. E/p K+K- K*K-+ K0 0 0 Readiness for data taking Carbon target: ~ 7•106 events • Spectrometer performance With RICH PID. Statistics: KS~ 90200  ~ 20000  ~ 9700 Counts Mass (GeV/c2)

  14. Readiness… • Performance and reliability of sub-detectors • Calibration and alignment • Reconstruction algorithms • Data Quality Monitoring • ….. Spectrometer considerably improved since 2002 Track finding efficiency (real data) 2000 : 86.9 ± 2.3 % 2002 : 96.5 ± 2.0 %

  15. Readiness.. J/ mm ’ • J/ trigger (signals, rates) Collection rate: 1000 J/psi per real hour (both channels) almost at hand ee

  16. Physics goals & Run plans The initial goal for 2002 • Measurement of the b cross section • Publishable charmonium physics • Investigation of physics program beyond 2002 2•106 J/ymonths running We Are Ready To Take These Data - complicated situation with HERA & planned new shutdown- we need SERIOUS physics data before shutdown OR collaboration will collapse

  17. 350.000 J/yc - 6.000 y’ - 350 b J/y Physics goal & run plan - present planning • Reduced time scale : 52 days stable running • with existing performance : • lower limit for meaningful charmonium program and B-cross section measurement • Mandatory prerequisite : stable and reliable HERA operation (moderate currents, no aggressive machine experiments..) • Run schedule : 75 % charmonium prod. 25% min.bias, calibration, tests.. ~1/6 of planned data sample

  18. Perspectives and Outlook • HERA-B in better shape than ever • Ready to take serious physics data NOW We need these data

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