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A. Meneguzzo Padova University & INFN Validation and Performance of the CMS Barrel Muon Drift Chambers with Cosmic Rays Cosmic rays are free, have no schedule , illuminate uniformly, are in all production sites..... Each chamber of the Barrel Muon System of the CMS experiment equipped with the final front-end and Low and High Voltage boards is fully tested in each assembly site in a cosmic rays facility. The system allows to check in real time the perfomances and the quality of the chambers and of the local trigger devices.The behaviour of the chambers built in the Legnaro INFN National Lab is reported and compared with Test Beam results. A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 Barrel muon system 5 wheels 30o sectors with 4 stations 250 DT chambers 2.0x2.5 m2 (MB1) 4.0x2.5 m2 (MB4) ~2*105 channels 480 RPC chambers MB4 MB3 MB2 MB1 A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 CMS Drift Tube Chambers “SuperLayer” (SL 2) (coord. in bending plane) SL (non-bending plane) honeycomb panel SL 1 Within one SL 4 layers staggered by half a cell to solve L/R ambiguity tA A B C D 42mm S 13mm W tB tC C tD g s a b b/a ~ .65 continuous lines represent electrodes dotted lines represent equipotential surfaces A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 Muon system specifications Muon identification (after >10 up to 2.4) Standalone momentum measurement Charge assignement (up to few TeV) Trigger on single and di-muons with variable Pt threshold up to 2.1 Bunch crossing assignment A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 Laboratori Nazionali di Legnaro (padova): DT chambers construction glue for I-beam LNL HV & LV boards A.T. Meneguzzo Padova University & INFN Padova Final chamber ICATPP 2003 Como 6-10 october, 2003 Barrel Muon : DT chamber requirements •drift time vs position linearity in the cell First Level Trigger (Mean time technique on staggered layers) • Bunch crossing identification • Track segment reconstruction •100mm precision on wire position within a SL • <1mm between SL Pt cut : sharp efficiency curve Muon track parameter •Resolution of 250mm/cell - muon ID coverage up to IhI=1.1 • Max Efficiency - momentum & charge assignement •Minimum Noise level we want to measure for each chamber Noise Efficiency Resolution Wire and Layer position accuracy SL F position accuracy A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 Chambers and Trigger set up at LNL Chamber under test Chamber under trigger test Local Trigger CCB Cosmic Rays : trigger set-up A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 Monitor and analysis SET UP The DAQ system is developed within the TRIDAS project; it has been used in the Test Beam 2000 , 2001, 2003 and at ISR (stoking area for final checks of all DT chambers). G.Maron et al. LNL Data Base Objectivity Flat File Analisys Off-line: -track reconstruction N.Toniolo LNL -trigger emulator MONITOR :on line analysis -ntuples production with –occupancy raw data and tracks information -noise -efficiency ORCA framework P.Ronchese et al., Pd -MT -Event Display ORCA framework Sara.Vanini et al., PD A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 Cell and drift time distribution checks 1800 V 3600V Strips good -1200 V Drift time bad but it can be recovered Bad cathod A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 Noise Noise of the channels in all layers of a chamber of all chambers channel channel 20 Hz/m A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 Noise vs Hv and noise vs Th Noise vs HV on the wire A.T. Meneguzzo Padova University & INFN Padova Noise vs FrontEnd Threshold ICATPP 2003 Como 6-10 october, 2003 Efficiency cell efficiency in the layer efficiency inside the cell geometrical inefficiency I-beam 1.2/42= 3% for normal tracks wire 1.00 0.96 A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 Efficiency :angle & all chambers Dead angle= 90 98% 99% Mean SL Efficiency for the first 12 chambers A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 Efficiency :diagnostic Efficiency in a layer :last 8 cells low efficiency Efficiency as a function of position inside the cells No voltage on the cathods A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 fit with ‘time’ Mean time y t t3 4 t2 t1 semicolumn 2 MT 234 t3 Tmax drift t 2 t 4 V d / Tmax 2 123 MT t2 Tmax t1 t3 d staggering 21000/ 380ns Vdrift=55mm/ns s= 1.6ns Wire position accuracy~70mm From the MeanTime distribution of the tracks in each semicolumn (semicell) we measure -the wire position accuracy from the width of the distribution of the Mean -the resolution and the resolution uniformity of the cells along the layer and in the SL Resolution=250mm Resolution smt=sqrt((s2-s trig_pm2) =3/2sl2 A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 MT: Layer displacement Example: layer 4 displaced of dx MT 234L Dt t4 t3 4 MT234R Dt = ( MT234R- MT234L) using the mean value of all MT234 ->good accuracy Layer 4 displacement -> Dx =Dt * vdrift t2 t1 MT123L MT123R 2 t3 Tmax t 2 t4 2 t3 Tmax t 2 t4 2d staggering t2 Tmax t 1 t3 Mean 378 ns Mean 383 ns A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 MT : signal wire propagation Measurement of the signal propagation along the wire vsignal=0.244 m/ns FEside vdrift=21/378=0.55mm/ns A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 MT summary Resolution in the cell Drift velocity in the cell Accuracy on staggering and wire position s1.7 ns 66 mm For all chambers A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 MT vs angle The apparent drift velocity grows with y angle;it is constant for F angle A.T. Meneguzzo Padova University & INFN Padova angle ICATPP 2003 Como 6-10 october, 2003 F Super Layers alignment All 4 point tracks, || < 20o 62215 mm build 4 point segment in each single SL x2 MB3_12 Extrapolate to the middle plane of the chamber x1 A.T. Meneguzzo Padova University & INFN Padova -3.80.1 mrad ICATPP 2003 Como corrections 6-10 october, 2003 before alignment Layer alignement : 7 point fit residuals <>=-1755 mm SL 1 SL 2 <>=205 mm MB3_12 <>=395 mm <>=655 mm A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 C2 fit vs SLs displacement c2 / NDOF all but one layer included (before layer alignment) 8515 mm Layer 1 excluded before layer alignment -0.50.1 mrad all layers included after layer alignment A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 after alignment corrections Como 6-10 october, 2003 DT Chamber performance in Test Beam MB2 :TEST BEAM 2001 Resolution and Plateau knee Hit rate in SL1 is 3.5 (1.7 for SL 2) larger than the worst case at LHC (shown SL1) 192 micron Drift cell effic.&resolution With increasing Background A.T. Meneguzzo Padova University & INFN Padova CMS Note 2003/007 192 micron ICATPP 2003 Como 6-10 october, 2003 DT Chambers: 1st Level Trigger SL2 BTI outer SL1 BTI inner H 4 points track L 3 points track BTI outer TRACO TSS/TSM H ** * * HH * BTI inner * H * * A.T. Meneguzzo Padova University & INFN Padova L * H * * HL (LH) ** H * * Ho * * * * ICATPP 2003 N * * * * * N * * Hi * * * * H Como 6-10 october, 2003 First Level Trigger set-up: functionality tests with cosmic rays The first final set up of the First Level Trigger has been tested on a MB3 chamber with a muon bunched beam at Cern in may 2003 (the test was successfully and preliminary results show perfect behaviour). The set up was first assembled and its functionaly checked at the assembly site in LNL. Here I presents the on line results of these first preliminary tests that showed us that the set up was correctly working. The real performance of the 1st Level Trigger have been studied on the test beam run and will come out soon. (Results of the performance of the BTI part of the 1st Level Trigger from Test Beam and with Magnetic field are in the CMS note01-051) output triggers with 3(L) or 4(H) hits trigger tracks in each SL ->correlated trigger Bunch crossing identification Angle trigger -450 450 Angle track A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 BunchedTB TB2003 2003DTchamberTriggerPreliminary DTchamberTriggerPreliminary Bunched trig. at 14bx efficiency = total # of events Event= scintillator + 2 hits in beam region tracks hitting 2 I-beams “EMULATOR” is a SW package that emulates the full chain of the Trigger Chips and Boards. It works offline and need as input the times recorded by the TDCs. “Emulator “ is not the CMS simulation,it should reproduce exactly the Trigger data. To compare with the expected performance as shown in the Trigger TDR we should compare with the full track reconstruction from TDC data. However this first result is in excellent agreement with what we expect. A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 ~ 98-99 % efficiency up to 350 Como 6-10 october, 2003 CONCLUSIONs The results of the tests performed in the production site with Cosmic Rays of each Barrel Muon Drift Chamber of the CMS experiment are very good and confirms the 2000(cms note01-051) ,2001 (cms note03-07) and 2003 Test Beam results: Noise Efficiency uniform cell layer vs phi angle vs theta angle Resolution Mean Time: cell layer phi angle theta angle Layer position accuracy SLs F position accuracy linear fit Trigger tests with cosmic <25 Hz/m 99% / layer ~ 250m/cell 100m/SL < 110 m all Layers/SL < 1mm good Cosmic rays are free, have no schedule , illuminate uniformly, are in all production sites. A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 The Installation Task help1 The Barrel Muon system comprises 250 chambers in 7 flavors: 5 4 60 60 60 40 10 10 10 3 2 1 6 7 8 9 10 12 11 MB1 MB2 MB3 MB4 MB1 MB2 MB3 3SL 3SL 3SL 2SL 2SL 2SL 2SL 2 RPC ~2.0 x 2.54 m2 960kg 2 RPC ~2.5 x 2.54 m2 1200kg 1 RPC ~3.0 x 2.54 m2 1300kg 1 RPC ~4.2 x 2.54 m2 1800kg 1 RPC 1 RPC 1 RPC F SL SL MB4 (Torino) Have two Superlayers only Honeycomb F SL 10 Sectors will be installed in SX5 => 210 Chambers(310 RPCs). Sectors 1 and 7 are used for the lowering fixture and will be installed in UX5 => 40 Chambers(60 RPCs). A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 42 mm Help cell C S g 13mm s continuous lines represent electrodes a W b b/a ~ .65 dotted lines represent equipotential surfaces the position of the s equipotential depends on the cell geometry (i.e. on the strip width and on the wire radius) the presence of the grounded Al plates and beams between S and C makes the position of the g equipotential quite independent of the Voltages of s and c Vw-Vs determines the GAIN in the gas : the request of a gain of ~ 10^5 determines the position of the s equipotential to be ~ 2.5 mm from the wire Vc ( and Vs) must generate in the region between c and g ( and between g and s ) an E field between 1 and 2 KV/cm to saturate the drift velocity A.T. Meneguzzo LHCC Comprehensive Padova UniversityReview & INFN10/2/01 Padova ICATPP 2003 CMS MUONS: Drift Tubes and Alignment Como 6-10 october, 2003 fabrizio Help schedule LNL 5/9/2003 Aachen 15/8 Madrid 10/9 96 SL 102 SL 120 SL 32 CH 34 34 CH 100 ch out of 210 Chambers at ISR Total MB1 MB2 MB3 20 28 25 by dec.03 73 29 38 30 97 These figures can imply that all the dressing will be done for all chambers at ISR (to be agreed) A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 Help BTI * aa * * * * Shift registers b * * * a +b = T A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 Help ISR A.T. Meneguzzo Padova University & INFN Padova ICATPP 2003 Como 6-10 october, 2003 BX Efficiency -2 Help TB2003 Traco CCB HH HL LL drop of correlated efficiency at large angles due to geometrical cuts (single BTI 56o traco 42o) Ho Hi Lo Li DT Trigger Performance - Sara Vanini 15 BTI test in Magnetic Field (test beam 2000, CMS note 2001/051) Help TB2000 BTI Prob. of one/4 layers affected by delta 16%, more than one 4% B (TESLA) longitudinal component CMS TN 051 2001 BW Bn .05 .1 .16 .21 .19 .38 .56 .77 1.15 .31 H-trig = 4/4 layers L-trig = 3/4 layers BTI n BTI n+1 A.T. B Meneguzzo (TESLA) radial component Padova University & INFN Padova .26 .96 ICATPP 2003 BTIs overlap Como 6-10 october, 2003