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Calorimeter Status. Robert Zitoun Stony Brook D Collaboration Week February 27, 2004. Operation. People. Run by shifters + “on-call experts” Mike Arov Ashish Kumar Silke Nelson Pierre Petroff (new coordinator) Kirti Ranjan Junjie Zhu ICD Andy White Barry Spurlock etc. L1Cal
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Calorimeter Status Robert Zitoun Stony Brook D Collaboration Week February 27, 2004 R. Zitoun, Stony Brook Collaboration Meeting
Operation R. Zitoun, Stony Brook Collaboration Meeting
People • Run by shifters + “on-call experts” Mike Arov Ashish Kumar Silke Nelson Pierre Petroff (new coordinator) Kirti Ranjan Junjie Zhu • ICD Andy White Barry Spurlock etc. • L1Cal Dan Edmunds Philippe Laurens • Dean Schamberger! R. Zitoun, Stony Brook Collaboration Meeting
Improved Hardware Operation • Calorimeter runs smoothly (only 37’ beam time lost since Jan 1st) • No power supply failure • BLS since Nov 24 ● preAmp since Dec 29 • Hardware replaced since Jan 1 • 3 BLS boards ●9 SCA daughter cards • Still problems (see later), but • Days of quick fixing are over • before swapping hardware, more detailed testing needed • replacing hardware in short access often harms more than it heals R. Zitoun, Stony Brook Collaboration Meeting
Improved Pedestal Runs • Upgrades • Settings by hand → Automatic settings (Silke N.) • x8 and x1 → x1 only when hardware change • 10 Hz → 20 Hz (Dean S.) • Download file production ~ 20’ → Only 4-5’ (Ursula B.) • “Random” trigger → Trigger walking through all SCA (uneven SCA population) cells (Dean S.) • Overall 20’ for inexperienced shifter • Last pain: needs SMT control • DB now accessible in framework R. Zitoun, Stony Brook Collaboration Meeting
Improved Calibration Runs • Before shutdown • 3 ramp runs taken and analyzed Feb ’02: “historic” run (non linearity coefficients in reco) Jan ’03 and Feb ’03 • Heavy data taking procedure • Since Dec 03: • Trivial data taking procedure (Silke N.) • Calibration done after each hardware change (~10 times) • Gain monitoring • calib done in “offline” mode (data written to tape, offline analysis) • soon “between store” run: 3 DAC settings (5’); written to DB R. Zitoun, Stony Brook Collaboration Meeting
Tools R. Zitoun, Stony Brook Collaboration Meeting
Pedestal Quality Tools ±1 count ±1 count d(×8 pedestal) d(×8 sigma) ±1 count d(×1 pedestal) d(×1 sigma) • Bad channels automatically killed before download • sparking channels: sometimes killed, sometimes not. Kill them permanently? • Comparison with a reference run • gives quality of the recent pedestal run R. Zitoun, Stony Brook Collaboration Meeting
Data Quality Tool • dq_calo: now supports L1 features (Slava Shary) zero bias jet triggers precision METx,y L1 R. Zitoun, Stony Brook Collaboration Meeting
Pedestal Viewer • Tool by Chris T. et al.: follow up of ped/noise values • Catches long term unwanted behavior • Have to learn it • Add diagnosis features more later R. Zitoun, Stony Brook Collaboration Meeting
Problems R. Zitoun, Stony Brook Collaboration Meeting
Occasional Hot Cells/Towers zero bias <energy> • Problem on BLS. Disappears by itself or at least after next ped run • However, ~2 pb–1 affected • Present policy • Kill only if L3 rate too high (also L1) • Can be corrected offline • Large effort by Slava Shary (at Orsay) on pre-shutdown data • Allows recovering much data. Still need work (<METx,y>) R. Zitoun, Stony Brook Collaboration Meeting
Occasional Warm Zones • Happened in 2 different places in the last month • Corresponds to individual BLS crates • Related to voltage instability (badly crimped 5Volt cable) • Shifts METx by 1 GeV • Florida State students (Fenghua D. and Haryo S.) working on slow control (archiving/recovery and problem detection) R. Zitoun, Stony Brook Collaboration Meeting
ADC noise caught by algorithm Not caught by algorithm • Set(s) of 384 channels have a pedestal shift (positive or negative) for a single event • Increases with (which?) rate • Timing and control problem?FPGA code suspected R. Zitoun, Stony Brook Collaboration Meeting
Gain Switching normal channel ×1 ×8 high ET e– in crate 10 (John G.) problem! ×1 ×8 • < 20 GeV, analog amplification by ×8 • > 20 GeV, digital amplification by ×8 • Sometimes digital ×8 not done • Timing and control problem? • Linked to the checkerboard pattern? R. Zitoun, Stony Brook Collaboration Meeting
Coming Next • New online tools • easy access to archived slow control data • slow control history • early alarms for dying channels: catch temperature rise, voltage drop • Improving present tools towards better/quicker diagnostics • Rewriting one unpacker: • too many archeological strata • too many unpackers • Offline Data Cleaning(next transparencies) • Calibration(next transparencies) R. Zitoun, Stony Brook Collaboration Meeting
Offline Data Cleaning • Now recording zero bias non zero suppressed data (full readout) • Allow computation of in-run pedestals and noise (not an easy task) • Flag off-centered cells/regions • Enter a DB • Correct for pedestal shifts or kill • Promising R. Zitoun, Stony Brook Collaboration Meeting
Calibration • Run I: signal integrated over a long time • Insensitive to precise signal shape: • calibration or physics • electronics parameters • Insensitive to timing • Run II: only ~2/3 of signal integrated • produce calorimeter response non-uniformity • increase constant term (may be not several percents!) • At the moment, just slope correction; no timing correction, no calib-phys difference • Plan to adapt ATLAS method to reduce non uniformity R. Zitoun, Stony Brook Collaboration Meeting
How to Calibrate Calorimeter? measured output known input H H phys cable, traces feed through calib preAmp + cables + shaper + SCA + BLS + ADC predicted known input • Measure individual channel transfer function H with calib data • Predict individual physics template pulse • Channel to channel correction at sampling time • Work started; still a long way. Will not solve the 4-5% constant term R. Zitoun, Stony Brook Collaboration Meeting
ALARM • People under the charm of conferences until end of March • Only look at pre shutdown data • Will rest until May • New rush towards summer conference • In June, will discover new problems; find unfixed old ones • Need people now (not in June) hunting for calorimeter problems by looking at data R. Zitoun, Stony Brook Collaboration Meeting