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Dimuon Spectrometer : Status of the tracking chambers
What’s in – what’s out Review of the components Chambers efficiency My personal view of the priorities for the shutdown
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ALICE Dimuon Spectrometer
y z x Dimuon Spectrometer
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What’s in – what’ out MCHVIEW of the noise At best we took data with stations 1,2 and 5, chamber 5, chamber 7 outside/left.
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MCH components review (simplified view!)
High Voltages Low Voltages Physics/PRL Detector Control System Sw interlocks FEE Offline analysis Ventilation Gas flow MCH detector FEE OCDB SAFETY Hw interlocks Physics Data MCH Readout CROCUS Geometry Monitoring System (GMS) Castor CAF LCG Pedestals, noises, gains ALICE DAQ Physics Data SHUTTLE Monitoring
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MCH Readout : Crocus/Trigger
Readout the MCH, manage busy and send data to DAQ annoying bugs found (causing busy of our readout) good handling of trigger sequences with : reject errors compliant with latest ALICE DAQ and Trigger (CTP) requirements nice tool (interfaced to our trigger crate) to monitor the busy of readout/Crocus. implements a full reset “button” Some news problems ? lost connection with 2565 and 2577 more about this in the last slides
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MCH components review (simplified view!)
High Voltages Low Voltages Physics/PRL Detector Control System Sw interlocks FEE Offline analysis Ventilation Gas flow MCH detector FEE OCDB SAFETY Hw interlocks Physics Data MCH Readout CROCUS Geometry Monitoring System (GMS) Castor CAF LCG Pedestals, noises, gains ALICE DAQ Physics Data SHUTTLE Monitoring
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MCH Detector Algorithm
The DA computes data taking condition parameters pedestal and noise per readout channel (μ,δ) give threshold for 0-suppression : critical parameter ! Mean and sigma values of pedestals ; Pedestal file generated by makeped ; ; structCrocusCmdHeader ; uiChecksum eCrocusCommand uiFrtCrtTargetIds[2] 0x 0x 0x 0x ; structFrtCrtCmdHeader #0 ; uiChecksum uiFrtCrtIdTarget uiFrtIdTargets[5] 0x000f0000 0x 0x000b0000 0x 0x000d0000 0x ; structFrtCmdHeader #0 ; uiChecksum eCrocusCommand uiFrtIdTarget 0x ; FRT 0x Lport 0 -> BP 6 0x 0x ; FRT 0x Lport 1 -> BP 7 ; FRT 0x Lport 2 -> BP 8 ; FRT 0x Lport 3 -> BP 9 ; FRT 0x Lport 5 -> BP 10 ; structRawDataHeader ; uiHeaderChecksum bLastChunk uiRawDataLength uiRawDataChecksum 0x 0x 0x000003cf 0x d ; RawData ; Lport 0 -> BP 6 with 3 manus ; Manu 16 (0x ) 0x 0x000000c2 0x 0x000000d1 0x 0x …. CROCUS Thresholds file FEE //=========================================================================== // NEW File calculated by makeped // * Statictics : 1000 // * # of MANUS : // * # of channels : // // //format : BUS_PATCH MANU_ADDR CHANNEL MEAN SIGMA … Flat ASCII file SHUTTLE
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MCH Detector Algorithm
The DA computes data taking condition parameters gain per readout channel Calibration method : linear + parabolic fits 9 (11 nowadays) DAC values + 2 functions => 3 parameters: a1, a2, threshold (xt) Measured DAC values (Data) Input DAC values (pad side) 5 4 3 1 8 9 6 7(t) 2 x<xt : f1(x)=a1 x + a0 x>xt : f2(x)=f1(xt) +a1 (x-xt) +a2 (x-xt)2 x-xt a2=1.6 E-04 P(2)=0.673 a0= a1= P(2)=0.934 threshold //================================================= // BP MANU CH a a thres Q //================================================= e f e f e fe e fd e fe ………..…. Flat ASCII file SHUTTLE
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MCH components review (simplified view!)
High Voltages Low Voltages Physics/PRL Detector Control System Sw interlocks FEE Offline analysis Ventilation Gas flow MCH detector FEE OCDB SAFETY Hw interlocks Physics Data MCH Readout CROCUS Geometry Monitoring System (GMS) Castor CAF LCG Pedestals, noises, gains ALICE DAQ Physics Data SHUTTLE Monitoring
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MCH Shuttle Shuttle transfers data taking condition parameters
gain per readout channel (calculated by the DA) pedestal and noise par readout channel (calculated by the DA) all high voltage channels (stored in the DCS database) to the Offline Condition DataBase (0CDB) mandatory for the offline analysis. MCH : pedestals, noises and gains = OK (DA updated recently to better handle parity errors) high voltages should be soon ok old problem now clearly identified and being solved GMS not tested/implemented !!
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MCH components review (simplified view!)
High Voltages Low Voltages Physics/PRL Detector Control System Sw interlocks FEE Offline analysis Ventilation Gas flow MCH detector FEE OCDB SAFETY Hw interlocks Physics Data MCH Readout CROCUS Geometry Monitoring System (GMS) Castor CAF LCG Pedestals, noises, gains ALICE DAQ Physics Data SHUTTLE Monitoring
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MCH alignment : Photogrammetry and Survey
Survey and Photogrammetry provides Day 0 misalignment file Survey chamber with respect to ALICE Photogrammetry slat or quadrant with respect to chamber Available for this run: chambers 1, 2, 3, 4 & 5 Ch1 Ch5 Javier Castillo
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MCH alignment with tracks
Global method: Simultaneous fit to misalignment and track parameters Millepede Input misalignments: Uniform |X,Y|<300 m ||< 500 rad Alignment precision: RMSX = 20 m RMSY = 10 m RMS = 20 rad 100k - 150k is a reasonable number Javier Castillo
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MCH components review (simplified view!)
High Voltages Low Voltages Physics/PRL Detector Control System Sw interlocks FEE Offline analysis Ventilation Gas flow MCH detector FEE OCDB SAFETY Hw interlocks Physics Data MCH Readout CROCUS Geometry Monitoring System (GMS) Castor CAF LCG Pedestals, noises, gains ALICE DAQ Physics Data SHUTTLE Monitoring
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MCH data monitoring : MOOD
MOOD (Monitoring Of Online Data): Tools for experts. Reads and Decodes raw data from either online stream or file. Visualisation of general information : pedestal, noise, gain, hitmap, errors, etc. Used for commissioning (noise display) and during cosmic runs (first cluster)
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MCH data monitoring : AMORE
AMORE (Automatic MOnitoRing Environment): Tools for shifters. Reads and Decodes raw data from online stream. Checks and reports the quality of data (at the raw data level only) Interfaced with the Quality Assurance framework of AliRoot. Tells to the shifter if we are taking crap or not and give a first diagnostic to the expert. Under development. MCHview-like display of information
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MCH components review (simplified view!)
High Voltages Low Voltages Physics/PRL Detector Control System Sw interlocks FEE Offline analysis Ventilation Gas flow MCH detector FEE OCDB SAFETY Hw interlocks Physics Data MCH Readout CROCUS Geometry Monitoring System (GMS) Castor CAF LCG Pedestals, noises, gains ALICE DAQ Physics Data SHUTTLE Monitoring
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MCH Safety : Interlocks
In terms of detector safety, you always want the belt and the straps power dissipated by the FEE required air cooling if air cooling stops shutdown the low voltages high voltages on the wire required clean Ar/CO2 mixture if input gas stops lower the high voltages “Hardwired” interlock for air cooling St1&2 cabled, tested and operating St3 cabled St4&5 to be done (not critical) [for the gas system, hardwired interlock could be cabled but it clearly appears unnecessary] “Software” interlocks (to be implement in DCS : work started) if temperatures sensors reach a too high value stop the LVPS if gas input or output flow is null set the HV to BEAM_TUNING Ultimately, shifters (in ACR) should not be necessary for MCH safety Presence on site of an-call expert
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MCH components review (simplified view!)
High Voltages Low Voltages Physics/PRL Detector Control System Sw interlocks FEE Offline analysis Ventilation Gas flow MCH detector FEE OCDB SAFETY Hw interlocks Physics Data MCH Readout CROCUS Geometry Monitoring System (GMS) Castor CAF LCG Pedestals, noises, gains HLT ALICE DAQ Physics Data SHUTTLE Monitoring
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HLT online display : the detector best friend/advertiser
Worked nicely in Feb/March ; TPC wasn’t running thus the “MUON TV” was on
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HLT online display : the detector best friend/advertiser
New implementation (better integration in Alieve) tested currently at CERN (HLT group) : ready for the first collisions…? Pedestal Display
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HLT online display : the detector best friend/advertiser
New implementation (better integration in Alieve) tested currently at CERN (HLT group) : ready for the first collisions…? Simulated Cluster
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HLT online display : the detector best friend/advertiser
New implementation (better integration in Alieve) tested currently at CERN (HLT group) : ready for the first collisions…? Simulated Track
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MCH components review (simplified view!)
High Voltages Low Voltages Physics/PRL Detector Control System Sw interlocks FEE Offline analysis Ventilation Gas flow MCH detector FEE OCDB SAFETY Hw interlocks Physics Data MCH Readout CROCUS Geometry Monitoring System (GMS) Castor CAF LCG Pedestals, noises, gains ALICE DAQ Physics Data SHUTTLE Monitoring
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MCH chamber efficiency for p+p 2008 run (ped. run 58492 12/09/08)
DDL id run p+p 2008 noise (0.8-5 ADC) noise ( ADC) other problems 2560 yes 99.70% 99.73% no 2561 99.65% 2562 94.67% 2563 98.54% 2564 99.81% 2565 99.76% 1 quadrant without HV 49.58% 2566 97.14% 2567 98.51% 98.59% 2568 -- 2569 14.08% 28.10% Slat02,04 have HV problems Eff <28% 2570 2571 12.66% 32.52% 2572 41.39% 62.50% 2573 2574 2575 2576 61.45% 67.21% 2577 55.37% 68.03% Slat11 with HV problems Eff <68% 2578 69.18% 74.85% 2579 station 1 station 2 station 3 station 4 station 5
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Propositions…. and my personal answers
Station 1 : 3 patch buses to fix qualitatively we can say that manas die continuously (see last slide) Station 2 : changing DE 303 (bottom quadrant on chamber 3 left) ? no : to risky for chamber 2 and 4. High probability to cause more damages than solving problems Chamber 4 at 99%, and then chamber 3 < 75% Station 3 one FRT to change (not sure but best guess) and try to improve the arrangement of the patch cables so nobody will ruin them (in my opinion, someone stomp –not step- on them) a dedicated team working on the noise of ch5 no lead so far (aluminum sheets help but not help the Xo) should not jump from commissioning to noise testing for 2 hours and then back to commissioning, etc…. Ch6 should be open and should not be connected before the noise is understood
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Propositions…. and my personal answers
Station 4 : Chamber 7 right should be the priority after full chamber 7 is readout correctly and only after that, one should think about working on chamber 8 Station 5 we had the 4 crocus of station 5 in the readout (next slide) missing DE when can they be repaired (if this is possible) is it worth to open the chambers to put them back some patch buses exhibit large fluctuations full bus patch over the threshold slows down the readout simplest is to remove them from configuration check voltages on the power lines ?
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General issues During the run (no work around the detector), we lost contact with : 10 patch buses on ch5 most probably the FRT Crocus chamber 9 right (sylvain couldn’t fix) Crocus chamber 3 left 2565 ? works fine now : “downward spiral” effect... + Crocus chamber 10 right became unstable (readout is fine and then not) after some time… Demonstrates the importance to perform long readout test before the cavern close. This needs to be understood as soon as possible : changing the board is not sufficient ! CRT/FRT must be returned to Orsay with proper form and proper packaging (anti-static) The database on the Twiki must be updated Commissioning logbook must be updated with relevant information It might appear a bit tedious but it is the only way to pinpoint and understand if problems are related to DSP/EPROM
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General issues MANAS are still dying with time (not investigated more). All station should provide some input to ?? I suggest to have somebody working on that best/easiest way : compare pedestal runs vs time (global tool) someone from India ? Power supplies : clearly the modified LVPS do not have a dramatic effect on the noise. Still some fluctuations ; all noises of St3,4,5 increased during week 37 Modifying the others LVPS (St1 and 2) would be a mistake : no clear gain or better understanding of the noise with the modified LVPS HV on quadrants/slats : a few can not hold the nominal voltages. But the current configuration is stable (see MCH twiki for details) can be easily tested in from the ACR (by slowly rising up the voltage and checking the stability)
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General issues Something must be done to avoid the screwdriver incident ! Access in the FASS, operation around/in the dipole or near station 4/5 should be supervised. We need to settle down a procedure with the Alice operation group to get, at least, informed.
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Spares slides First Physics more on trigger chambers
Javier’s slides on alignment Jean-Luc slides on calibration : pedestal, noise, gain, fit quality Thanks to Indranil, Javier, Jean-Luc, Guillaume, Laurent for preparing some slides for me
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MUON Spectrometer performances: J/
10k J/ in acceptance Full simulation “Hit errors” increased by 1mm to keep constant efficiency Resolution ~ 100 m seems satisfactory Resolution ~ 50 m perfect Javier Castillo 32 32
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MUON Spectrometer performances:
10k in acceptance Full simulation “Hit errors” increased by 1mm to keep constant efficiency Resolution < 50 m needed Javier Castillo 33 33
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MUON performances - momentum resolution
Muons from J/ Muons from X,Y=1000 m X,Y= 700 m X,Y= 500 m X,Y= 300 m X,Y= 100 m X,Y= 50 m X,Y= m Javier Castillo 34 34
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MUONTRK_DA : Pedestal mean value
Pictures obtained after analyzing 3 runs: [St_1] , [St_2 + ½ Ch_5 + ½ Ch_7], [St_5]
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MUONTRK_DA : Pedestal sigma value
Ch_5 (St_3) are particularly noisy Noise has to be improved in some slats of St_5 Right
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MUONTRK_DA : gain parameter a1
Green color indicates Gain mean values around 4 mV/fC
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MUONTRK_DA : linear quality fit [range: from 1 (bad) to 15 (good)]
For un-calibrated channels (no a1 extracted) : quality fit codes are forced to 0 and a1 to 0.5
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