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AFEB timing in CSCs in splash events, run 120042. N. Terentiev, CMU CSC Synchronization meeting Nov. 16, 2009, CERN. Introduction. Data: run 120042 splash events (475 events available) beam 2 goes from ME- to ME+ CMS trigger is provided by ECAL
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AFEB timing in CSCs in splash events, run 120042 N. Terentiev, CMU CSC Synchronization meeting Nov. 16, 2009, CERN
Introduction • Data: • run 120042 splash events (475 events available) • beam 2 goes from ME- to ME+ • CMS trigger is provided by ECAL • using "collider" mode of CSC timing • ME- was delayed by 2 BX to coincide with ME+ • Analysis: • CMSSW_3_2_2, dataset /BeamHalo/BeamCommissioning09-v1/RAW • CSCValidation package (modified module doAFEBTiming) • CSCWireDigi collection provides for each hit in CSC layer: • wire group number • 25 ns time bin number where the hit was latched by ALCT ("time bin ON") • up to 16 non empty time bins recorded
Introduction • doAFEBTiming module outputs for each CSC: • 2D distribution of the first time bin number which is ON versus the wire group (presented with use of AFEB channel number, left figure) • 2D distribution of the number of time bins ON versus the wire group (right figure) • we are using MEAN of the first time bin number ON distribution for timing • number of time bins ON is sensitive to AFEB oscillations and pickup noise.
Analysis • In splash events anode mean timing distributions are not flat within CSC (examples are for ME-3/2/15) • To have global picture for all CSCs use MEAN averaged over • first 3 AFEBs (narrow part of the chamber, "bottom") and • last 3 AFEBs (wide part of the chamber, "top"), see next slides.
Analysis • In cosmic muons data from CRAFT2009 anode mean timing distribution is within 1 BX in each CSC ( example for ME-3/2/15, right, see also backup).
Analysis • Timing in ME1/1
Analysis • Timing in ME1/2
Analysis • Timing in ME1/3
Analysis • Timing in ME2/1
Analysis • Timing in ME2/2
Analysis • Timing in ME3/1
Analysis • Timing in ME3/2
Analysis • Timing in ME4/1
Analysis • Timing in ME4/2
Summary • Anode timing in Nov. 2009 splash events (run 120042) • still different for ME+ and ME- • approximately flat in CSCs in inner rings (within 1BX) • anode signals come later by ~1-1.5 BX in outer parts of CSCs ("top") of outer rings ME2/2 and ME3/2 in both endcaps • splash events hard to interpret due to extremely high occupancy of anode wires and cathode strips in CSCs • coming beam halo events should provide more clear picture
Backup • Timing in ME1/1 (CRAFT 2009 Summer)
Backup • Timing in ME1/2 (CRAFT 2009 Summer)
Backup • Timing in ME1/3 (CRAFT 2009 Summer)
Backup • Timing in ME2/1 (CRAFT 2009 Summer)
Backup • Timing in ME2/2 (CRAFT 2009 Summer)
Backup • Timing in ME3/1 (CRAFT 2009 Summer)
Backup • Timing in ME3/2 (CRAFT 2009 Summer)
Backup • Timing in ME4/1 (CRAFT 2009 Summer)
Backup • Timing in ME4/2 (CRAFT 2009 Summer)