CDC prototype drift times

CDC prototype cosmics data

• 50/50 mixed Ar, CO₂
• Recalibrated MFCs
• Outer plenum added to CDC prototype to prevent leaks
• New pre-production HVB
• 2100V
• Modified preamp4 (terminating resistors removed)
• Prototype tilted at 30^o to enclosing scintillators (scints trigger the daq)
• New timing setup (recording coinc logic signal)

Purple histogram is drift time in tracks through each straw; gray selects tracks through all 3 straws in same column

drift times for all tracks and tracks in single column of straws, threshold 5 sigma

drift times for all tracks and tracks in single column of straws, threshold 10 sigma

Below: Purple:all tracks through straw, grey: track angle 5° or more to vertical, light blue: track angle less than 5° to vertical. Hit threshold 5 sigma over pedestal

drift times for all tracks, tracks angled at 5° or more to vertical and at less than 5° to vertical, threshold 5 sigma

Same again just for straw 17

single column of straws, threshold 5 sigma

single column of straws, threshold 10 sigma

track angles, threshold 5 sigma

Fitted drift distance for straw 17, for all tracks, and tracks through all 3 straws in the same vertical column, hit threshold 5sigma (left) and 10sigma (right)

fitted drift distance for straw 17 (straw 17 is 20th in the root tree) for all tracks and same-column tracks, threshold 5sigma

fitted drift distance for straw 17 for all tracks and same-column tracks, threshold 10sigma

Same again with more bins

fitted drift distance for straw 17 (straw 17 is 20th in the root tree) for all tracks and same-column tracks, threshold 5sigma

fitted drift distance for straw 17 for all tracks and same-column tracks, threshold 10sigma

Trigger signal (derived from coinc unit)

trigger times

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Threshold crossing bins for straw 17 and different thresholds (using one simple threshold as a multiple of pedestal std dev plus mean of pedestal for bins 90-190 bins, t0 is approx bin 198)

Threshold crossing bins for straw 17

Threshold crossing bins (all straws) with multiple hits in the same bin

Threshold crossing bins for 3 or more hits, threshold 3sigma

Threshold crossing bins for multiple hits, threshold 3sigma

Threshold crossing bins for 3 or more hits, threshold 5sigma

Threshold crossing bins for 3 or more hits, threshold 10sigma

Threshold crossing bins for ch20 (straw 17) in coincidence with other straws in the same horizontal row, chs 22 - 20 - 19 - 15

Threshold crossing bins for chs 22 and 20, threshold 5sigma

Threshold crossing bins for ch 20, threshold 5sigma

Threshold crossing bins for chs 19 and 20, threshold 5sigma

Threshold crossing bins for chs 15 and 20, threshold 5sigma

3sigma threshold crossing bins for other straws in the same horizontal row in coincidence with ch20

Threshold crossing bins for ch 22, threshold 3sigma

Max amplitude for ch20, threshold 3sigma

Threshold crossing bins for ch 19, threshold 3sigma

Threshold crossing bins for ch 15, threshold 3sigma

5sigma threshold crossing bins for other straws in the same horizontal row in coincidence with ch20

Threshold crossing bins for ch 22, threshold 5sigma

Max amplitude for ch20, threshold 5sigma, 4197 events with > 1 hit in same row (12% of >0 hits)

Threshold crossing bins for ch 19, threshold 5sigma

Threshold crossing bins for ch 15, threshold 5sigma

10sigma threshold crossing bins for other straws in the same horizontal row in coincidence with ch20

Threshold crossing bins for ch 22, threshold 10sigma

Max amplitude for ch20, threshold 10sigma, 3845 events with > 1 hit in same row (11% of >0 hits)

Threshold crossing bins for ch 19, threshold 10sigma

Threshold crossing bins for ch 15, threshold 10sigma

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Drift times run 31724 (30^o to horizontal, 2100V) where drift time (ns) is cdc time - trigger time + 100 and cdc time is the time extracted from the cdc signal x 8ns.

Ch23 cdc time - trigger time hit thr 5sigma timing thr 1sigma, bump intervals 11, 25, 24, 28, 22, 26 (mean 22.7, 25.0 excluding 11)

Ch20 cdc time - trigger time hit thr 5sigma timing thr 1sigma, bump intervals 29, 21, 31, 24, 29, 30 (mean 27.3)

Ch20 cdc time hit thr 5sigma timing thr 1sigma, bump intervals 25, 24, 28, 19 (mean 24.0)

Drift times run 31757 (horizontal, 2100V)

Ch23 cdc time - trigger time hit thr 5sigma timing thr 1sigma, bump intervals 30, 23, 26, 25, 30 (mean 26.8)

Ch20 cdc time - trigger time hit thr 5sigma timing thr 1sigma, bump intervals 24, 21, 26, 26 (mean 24.3)

Ch20 cdc time hit thr 5sigma timing thr 1sigma, bump intervals 15, 11, 20, 14, 17 (mean 15.4)

Drift times run 31761 (25^o to horizontal, 2100V) where drift time (ns) is cdc time - trigger time + 100 and cdc time is the time extracted from the cdc signal x 8ns. Before this run I disabled the 125MHz clock circuit feeding the (unused) Struck fADCs.

Ch23 cdc time - trigger time hit thr 5sigma timing thr 1sigma, bump intervals 15, 30, 21 (mean 25.5)

Ch20 cdc time - trigger time hit thr 5sigma timing thr 1sigma, bump intervals 47,45 (mean 46)

Ch20 cdc time hit thr 5sigma timing thr 1sigma, bump intervals 22, 28, 21, 24 (mean 24.0)

Drift times run 31744 (horizontal, 2300V, 40%Ar 60%CO2) where drift time (ns) is cdc time - trigger time + 100 and cdc time is the time extracted from the cdc signal x 8ns.

Ch20 cdc time hit thr 5sigma timing thr 1sigma, bump intervals 21,31,35

Drift times run 31746 (horizontal, rolled over onto one edge, 2300V, 40%Ar 60%CO2) where drift time (ns) is cdc time - trigger time + 100 and cdc time is the time extracted from the cdc signal x 8ns.

Ch20 cdc time hit thr 5sigma timing thr 1sigma, bump intervals 20,29

Bump at 117ns after t0 for 40/60 gas corresponds to approx 3.3mm from wire, same time for 50/50 corresponds to ~3.5mm from wire. A hit 3.5mm from the wire in 40/60 gas would be at 130ns, moving to 118ns for 50/50.