Download presentation
Presentation is loading. Please wait.
Published byAda Walker Modified over 9 years ago
1
28 June 2010 LHCb week St Petersburg M.N Minard 1 Calorimeter status Hardware status Controls & monitoring Timing alignment Calorimeters calibration Pending issues
2
28 June 2010 LHCb week St Petersburg M.N Minard 2 Calorimeter detectors status Non working channels Non working LED Concerns ECAL7/601610 cells + 11 unstable Fuse robustness HCAL3/14482 noisy PS0/6016Mostly Ok LED Not used SPD0/601610% channels LED not used Trigger impact
3
28 June 2010 LHCb week St Petersburg M.N Minard 3 Calorimeters controls Daily control followed by piquet (12 ) : –9 days with 2 days overlap HV errors (April) DAQ errors or configuration errors OPC server –Daily checks of currents and power supllies –Analyse calibration farm summaries ECS -Updated for Temperature controls of VFE -System very stable.
4
28 June 2010 LHCb week St Petersburg M.N Minard 4 Calorimeters monitoring (1) Calibration farm monitoring : LED Ped Survey -Pedestal noise & shift -Chi2 Presenter Expert Expert trend
5
28 June 2010 LHCb week St Petersburg M.N Minard 5 Calorimeters monitoring (2) LED data flashing at 10Hz are used to monitor the ECAL & HCAL calorimeters –Survey LED response Stability PMT/pin ratio –Give Trend Problem rate Algorithm in progress –Should provide: Dead channels Gain change Still a lot of improvements foreseen : –Data manager & data quality –DB handling
6
28 June 2010 LHCb week St Petersburg M.N Minard 6 Calorimeters Timing
7
28 June 2010 LHCb week St Petersburg M.N Minard 7 Xcal Timing status = 0.75ns Crate <>= 0.7ns
8
28 June 2010 LHCb week St Petersburg M.N Minard 8 Xcal response stability K1 =Central/ Central+next+2*prev crate K1 <> = 0.93 = 0.008 8 15 21 Crate # Channel+-1ns +-2ns Eprs>90MeV <>= 0.93 = 0.012 1% ns
9
28 June 2010 LHCb week St Petersburg M.N Minard 9 PS timing Spill over correction Not implemented – in progress All board < 1ns On TAE determine the 0 asymetry
10
28 June 2010 LHCb week St Petersburg M.N Minard 10 SPD timing Move by 1ns to be safe Initial adjustment from occupancy 0.5 ns off Clock shift Check with dispaced events
11
28 June 2010 LHCb week St Petersburg M.N Minard 11 SPD spill over At data taking start spill over has consequence on trigger –Work conducted to estimate the effect importance – lab tests & 2010 data used Substrator work as expected compensated for 20% of signal Exist particles arriving late : estimated spillover 4;10 -3 Effect low compare to backsplashs … PS/SPD survey with LED to resume
12
28 June 2010 LHCb week St Petersburg M.N Minard 12 Calorimeters calibration
13
28 June 2010 LHCb week St Petersburg M.N Minard 13 Hadronic calorimeter calibration Relative calibration monitored by Cesium source ;Ref 5 Feb 2010 Variation within 3 months To be compared to LED data
14
28 June 2010 LHCb week St Petersburg M.N Minard 14 Yu. Guz 02/06/201014 Response uniform at ~3% RMS for both inner and outer HCAL calibration on data at 4% level in progress. Hadronic calorimeter calibration
15
28 June 2010 LHCb week St Petersburg M.N Minard 15 Electromagnetic calorimeters calibration sequence Adjusted using 0 mass constraint : - 2 selected Et >205Mev - SPD to be calibrated.Account for # leakages default values from MC. Cell calibration c i - initial gain adjustment from PE (8%) - Eflow calibration (4%) -> early April (1) - Fine calibration (4). E prs calibration (MIP) (2). adjustment (3) E Ecal = c i E i
16
28 June 2010 LHCb week St Petersburg M.N Minard 16 SPD calibration Threshold adjustment of SPD –Run taken for theoritical 0.3, 0;5, 0;8, 1. MIP Numerical description Analytical description Correction to the current settings (active) 3% channels no setting value Need 2 more points 1.4 and 1.8
17
28 June 2010 LHCb week St Petersburg M.N Minard 17 E-flow PS & ECAL First relative inter-calibration on collision data using an ‘energy flow’ method smoothing the transverse energy deposit on the basis of the average deposit of neighbour channels Calorimeter standalone method requiring a relatively small statistics (~ 1M events) Method can be applied to PRS & HCAL Eflow-> 4-5% PS calibration Uses MIP response in PRS individual cells Intercalibration at 5% level Typical cell
18
28 June 2010 LHCb week St Petersburg M.N Minard 18 Estimation of the energy before ECAL ( PS+X) Adjusted from the 0 width mass minimization as a function of , for the different calorimeter regions. varies +-25% for region Width Mass Chi2
19
28 June 2010 LHCb week St Petersburg M.N Minard 19 Fine cell calibration Iterative method developed for fine cell calibration : –Take converter or non converted photon –A tool building and iteratively using FMDst has been built (Kali) –Exercised on 100M decalibrated data Mass vs iteration After Mass 138.8 -> 135 MeV Width 12.55-> 9.72 MeV
20
28 June 2010 LHCb week St Petersburg M.N Minard 20 Method performance & limitations Adjusted/true : sigma = 2.25% With tail ~3.5% Border effect, to be corrected from MC
21
28 June 2010 LHCb week St Petersburg M.N Minard 21 Cell calibration on data Use mass scale and minimize width Use 80M data ‘ (+70) including Eflow/PRS/ calibrations Iterative procedure /cell Max(prs1,prs2) 7.2 MeV Prs1 > 10 MeV Prs2 7.54 MeV Min(prs1,prs2)>10 MeV -> 8 MeV 5.78 Mev ( but 2 gaussian) MC width expectation 9MeV
22
28 June 2010 LHCb week St Petersburg M.N Minard 22 2 approaches give coherent results Differences mostly in outer part And detector border These calibrations are available in Reco04 Are they used in the PID for HLT ? Adjustment needed ?
23
28 June 2010 LHCb week St Petersburg M.N Minard 23 PMT stability over 2 months Estimate of stability for cell i: “Pessimistic”: S1(i) = (Max(i) – Min(i)) / Mean(i) 3.4% “Optimistic”: S2(i) = rms(i) / Mean(i) (0.7%) Max Min rms mean Algorithm to be worked
24
28 June 2010 LHCb week St Petersburg M.N Minard 24 On going questions Remeasure from data sample corrections issued from MC: –Z shape –S shape –Leakages Same cell coefficient for photon & electron : work on (in progress) and others corrections New iteration foreseen after work completion Calorimeter alignment vs trackers Understanding MC behavior ( lateral shower expansion )
25
28 June 2010 LHCb week St Petersburg M.N Minard 25 Nice electromagnetic Zoo Is it going to survive ?
26
28 June 2010 LHCb week St Petersburg M.N Minard 26 High pile up events & on line reconstructed 0 0/background decrease by 25-30%, In spite new calibration applied Study to be done on others caracteristic channels May data Last week end data
27
28 June 2010 LHCb week St Petersburg M.N Minard 27 Status & plans Calorimeter hardware and controls performs well. Large progress have been made in detector understanding 1st fine calibration is released since end of May and Repro04 uses it … Still a lot to do for the 1% calibration goal at high energy …will need high energy sample.
28
28 June 2010 LHCb week St Petersburg M.N Minard 28 Back up
29
28 June 2010 LHCb week St Petersburg M.N Minard 29 High pt 0
30
28 June 2010 LHCb week St Petersburg M.N Minard 30 Electron Electron correction to be tuned for PRS & leakage
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.