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

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

3. Detector status Status (compared to 2000) VDSFully operational (always was) ITRGetting into operation… OTRImproved stability, less noise RICHFully operational as in 2000 ECALSubstantially improved MuonStable, not perfect but working  

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

5. ITR-2 New problem observed recently ~25% of channels show no signal ! normal chamber abnormal chamber REASON UNCLEAR Due to high redundancy in ITR: Coverage and efficiency of tracking still sufficient Run 19990 ITR-tracks at exit of PC section 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 2000RECENT GOOD80.4 %93.3 % NOISY5.1 %1.5 % DEAD14.5 %5.2 % Channel statistics threshold, noise at 1% (-) (+) Cell efficiency >95 %, fine for triggering and tracking

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

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

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/  ->µµ online

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

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

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

13. Readiness for data taking Spectrometer performance Carbon target: ~ 710 6 events K0K0 00 00 E/p Counts Mass (GeV/c 2 )  K + K - With RICH PID. K*  K -  + Statistics: K S ~ 90200  ~ 20000  ~ 9700

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

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

16. Physics goals & Run plans  Measurement of the b cross section  Publishable charmonium physics  Investigation of physics program beyond 2002 The initial goal for 2002 210 6 J/  months running We Are Ready To Take These Data we need SERIOUS physics data before shutdown OR collaboration will collapse - complicated situation with HERA & planned new shutdown-

17. 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.. Physics goal & run plan - present planning 350.000 J/  c - 6.000  ’ - 350 b J/   ~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