Calibration Status online calibration pedestal calibration pulser calibration
Calibration Status online calibration: ·pedestal calibration ·pulser calibration offline calibration (em): ·geometry dependent corrections ·scale-corrections Z ee ·Et/pt studies at different energies ·energies in -cracks 11/1/2020 1
Pedestal calibration: strategies ·imminent: deployment of new calibration databases and associated validation scheme ( status calorimeter meeting tomorrow) ·possible online calibration strategies: · pedestal reference run: 10 k events/gain path used for download and offline 0 -suppression · pedestal monitoring run: 500 events/gain path used for monitoring pedestal drifted channels to be flagged, killed? updated? ·Pedestal Calibration Validation - flags and kills channels with: · incorrect mean/sigma values · drift values 11/1/2020 2
Pedestal calibration: mean/sigma ·monitoring run: 500 events ·mean: 10 cut 470<mean<770 ·sigma: 10 cut sigma<40 11/1/2020 3
Pedestal drift ·reference and monitoring run taken one after the other ·(mean-ref) 500/sigma: 5 cut ·sigma-ref: cut at 2? ·gain 8/gain 1 differences? 11/1/2020 4
Pulser calibration: strategies · 3 standard set of linearity runs: gain 8: 80 steps of DAC-step 20 (~20 Me. V) gain 8: 80 steps of DAC-step 200 gain 1: 80 steps of DAC-step 1600 · monitoring pulser run: free gain: 2 steps DAC=5000 and DAC=15000 · timing calibration: gain 8, DAC=5000, 50 steps of delay=5 (~10 ns) status: 2 sets of gain/nlc calibration coefficients (2002/2003) taken at fixed timing no corrections applied 11/1/2020 5
Pulser calibration: offset ·determination of gain coefficients and nlc corrections x offset ·negative pulser offset (i. e. DAC=0 gives already a pulse) NLC corrections at small energies 9 11 4 3 2 8 6 1 ·DAC-component exchanged on pulsers during shutdown ·possibility to download offset for each pulser (trigger studies) Robert Zitoun 11/1/2020 6
Pulser: delay correction factors ·slope determined by linearity ramps depends on delay value delay used for calibration at pulse max ·correction factors can be determined for difference between delay used for calibration and delay at max. signal height ·but: relative difference in delay corresponds to relative difference in timing for physics signal if not too far ·possibility to optimize delay per 1/6 of each pulser via automatic download correction factors Stephanie Beauceron 11/1/2020 7
Pulser: pulse shape corrections Sergey Burdin ·correction factors taking into account difference in signal shape between calibration pulse and physics signal ·determination from pulse shape simulation: good agreement for calibration pulse, ambiguity for physics signal between scope measurement and triple sampling data ·triple sampling data with +/-5 ticks 11/1/2020 8
em-calib: geometry dep. corrections p 10 5 Ge. V CC p 13. 06 0, 7 Ge. V 0, 2 Ge. V 50 Ge. V 0, 5 Ge. V 1, 6 Ge. V Anne-Marie Magnan important as long as no PS energies are used more important with p 13. 06 no done for p 13. 08, smaller? 11/1/2020 9
Energy in EC Calorimeter EC 50 Ge. V p 13. 06: energy from floors p 10 Not the same behaviour! Anne-Marie Magnan 11/1/2020 10
MC energy resolution Run I Eta corrections p 10 No correction p 13 Eta corrections p 13 s 0. 15 0. 202 ± 0. 006 0. 19 ± 0. 01 0. 199 ± 0. 008 b 0. 16 0. 23 ± 0. 10 0. 59 ± 0. 08 0. 42 ± 0. 08 c 0. 003 0. 004 ± 0. 002 0. 0085 ± 0. 0014 0. 0076 ± 0. 0014 CC Anne-Marie Magnan ·higher noise term in MC p 13 than p 10 and in Run 1 ·to be determined from data: constant term? 11/1/2020 11
scale correction Z ee ECN x 43 x 42 x 48 ECS Alexis Cothenet x 49 ·scale factors derived in calorimeter detector regions ·~1000 events with p 13. 05 data 11/1/2020 12
Z-mass peak Alexis Cothenet ·after all corrections · 2 tracks matching required ·resolution larger than in MC 11/1/2020 13
Et/pt comparison 1. 10 ·Et/pt comparison for different energy regions after geometry dependent corrections 1. 00 ·where all these electrons coming from? ·pt< 10 Ge. V underestimated? 0. 97 1. 04 0. 92 Oleg Kouznetsov 1. 01 1. 07 0. 78 ·pt>40 Ge. V overestimated? MC: Egen mean sigma 5 Ge. V 0. 96 0. 19 10 Ge. V 0. 98 0. 20 50 Ge. V 1. 0 0. 20 200 Ge. V 1. 0 0. 31 11/1/2020 14
Et/pt: resolution Oleg Kouznetsov ·from p 11 data 11/1/2020 15
energy in -cracks: Et/pt Oleg Kouznetsov ·studies for p 13 underway ·corrections with FH 1 energy not possible after realistic MC simulation 11/1/2020 16
Summary ·“final” online calibration procedure is (slowly…) coming together better following of the calorimeter behavior better data quality ·correction to gain/nlc calibration to be studied ·good MC is crucial for offline calibration: changes with p 13. 08 in geometry dependent corrections… ·Z resolution not understood yet ·promising distributions from E/p 11/1/2020 17
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