CDC 50 50

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50/50 Ar/CO2 and cosmics, prototype horizontal

Short runs for range of HV, check pedestal is ok and find MPV

2050V, 50/50 gas, prototype horizontal
Pedestal mean of samples 0-99, ch20, over 1 day
Pedestal std. dev. of samples 0-99, ch20, over 1 day
Max amplitude ch20, hit threshold 4sigma
Max amplitude ch20, hit threshold 5sigma
2075V, 50/50 gas, prototype horizontal
Pedestal mean of samples 0-99, ch20, over 1 day
Pedestal std. dev. of samples 0-99, ch20, over 1 day
Max amplitude ch20, hit threshold 4sigma, excluding last 7k events
Max amplitude ch20, hit threshold 5sigma, excluding last 7k events


2100V, 50/50 gas, prototype horizontal
Pedestal mean of samples 0-99, ch20, over 1 day
Pedestal std. dev. of samples 0-99, ch20, over 1 day
Max amplitude ch20, hit threshold 4sigma, excluding first 2k events
Max amplitude ch20, hit threshold 5sigma, excluding first 2k events


2090V, 50/50 gas, prototype horizontal
Pedestal mean of samples 0-99, ch20, over 1 day
Pedestal std. dev. of samples 0-99, ch20, over 1 day
Max amplitude ch20, hit threshold 4sigma
Max amplitude ch20, hit threshold 5sigma

Fit max amplitude histograms and find optimal HV

Where to start the fit from.

50/50 gas, prototype horizontal, 4sigma (gray) and 5sigma (blue) hit threshold, fit range 6sigma+
2090V, Landau fits, log likelihood method, fit range starting at 5, 6, 7, 8 x pedestal sigma
2090V, zoomed in

The fits started at higher amplitude underestimate the width. Fit range starting at 5pedestalsigma has MPV 204.5, Sigma 61.9, MPV/Sigma 3.3. Fit range starting at 6pedestalsigma has MPV 208.6, Sigma 60.7, MPV/Sigma 3.4. Fit range starting at 7pedestalsigma has MPV 213.7, Sigma 59.5, MPV/Sigma 3.6. Use 5pedestalsigma start.


50/50 gas, prototype horizontal, 4sigma (gray) and 5sigma (blue) hit threshold, fit range 5sigma+
2075V, lines show 99.7%, 99% and 95% of landau summed 0-4000 (51, 66, 95)
2090V, lines show 99.7%, 99% and 95% of landau summed 0-4000 (55, 74, 111)
2100V, lines show 99.7%, 99% and 95% of landau summed 0-4000 (59, 80, 121)



50/50 gas, noise std dev 16.5, hit threshold 5x16.5 = 82.5
HV Fit MPV Fit sigma (FWHM/4) Fit 4sigma/MPV MPV/sigma 4045/MPV 99% point 97% point 95% point
2075 169 49 1.16 3.5 24 66 84 95
2090 204 62 1.21 3.3 20 74 97 111
2100 225 69 1.22 3.3 18 80 106 122


2090V - Find best point to take as local pedestal

Find out where to take local pedestal. These are plots of change in ADC value vs time relative to the threshold crossing time.

2090V 50/50 Change in ADC value vs time relative to the threshold crossing time (in units of 8ns/5)
2090V, hit thr 5 ped-sigma

Mean goes through 0.5 and 1 at -17.2 and -14.4 for thr=5sigma

Fit drift time histogram and find t-zero

Drift time for 2090V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=0
2090V, hit threshold 5sigma, time thresholds 4 and 1 sigma Estimate of t0 is 88 and tmax is 756, difference is 668, straight-line intercept is 79.2, to match histogram fit t0, use tz_add 8.4
Same, x-axis expanded

Max drift time according to Garfield is 663ns for 50/50 Ar/CO2, 671ns for 49.5/50.5, 678ns for 49/51.

Tracking efficiency plot

Tracks/Triggers, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17
tzero=88ns, early hits ignored
tzero=88ns, early hits reassigned to tzero+4ns


Look at position resolution, find best gas mix for Garfield x-t tables

Find gas mix which puts the mean residuals for the tracks with drift distance 5mm+ closest to zero

Resolution for 2090V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, 50/50 Garfield
50/50 Garfield, resolution ch 20
50/50 Garfield, resolution vs hit radius
50/50 Garfield, resolution ch 20 for tracks of radius 5mm+
Resolution for 2090V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, 49.7/50.3 Garfield
49.7/50.3 Garfield, resolution ch 20
49.7/50.3 Garfield, resolution vs hit radius
49.7/50.3 Garfield, resolution ch 20 for tracks of radius 5mm+
Resolution for 2090V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, 49.5/50.5 Garfield
49.5/50.5 Garfield, resolution ch 20
49.5/50.5 Garfield, resolution vs hit radius
49.5/50.5 Garfield, resolution ch 20 for tracks of radius 5mm+
Resolution for 2090V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, 50/50 Garfield
50/50 Garfield, resolution vs track radius
50/50 Garfield, resolution vs track radius
Resolution for 2090V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, 49.7/50.3 Garfield
49.7/50.3 Garfield, resolution vs track radius
49.7/50.3 Garfield, resolution vs track radius


Resolution for 2090V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, 49.5/50.5 Garfield
49.5/50.5 Garfield, resolution vs track radius
49.5/50.5 Garfield, resolution vs track radius


Reassign pre-tzero hits

Include previously ignored hits which arrived before tzero+tz_add, assign these to a fixed drift time

2090V 49.5/50.5 Garfield etc Resolution for np=17, tz_add=8ns, hits before t-zero reassigned
tfix = 1000 (ignored), 0, 1ns
tfix = 1, 2, 3ns

Fit with sum of 2 gaussians

2090V 49.5/50.5 Garfield etc Resolution for np=17, tz_add=8ns, hits before t-zero reassigned
tfix = 1ns
tfix = 2ns
tfix = 3ns
tfix = 4ns
tfix = 5ns
tfix = 6ns


Resolution for 2090V, 49.7/50.3 Garfield, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, tfix=4ns
49.7/50.3 Garfield, resolution ch 20
49.7/50.3 Garfield, resolution vs hit radius
49.7/50.3 Garfield, resolution ch 20 for tracks of radius 5mm+

Max drift times from Garfield for 2090V, various gas mixes and 295K
Ar(%) CO2(%) tmax(ns)
49.0 51.0 691
49.1 50.9 688
49.2 50.8 688
49.3 50.7 686
49.4 50.6 684
49.5 50.5 683
49.6 50.4 682
49.7 50.3 679
49.8 50.2 679
49.9 50.1 675
50.0 50.0 676
Resolution for 2090V, 50/50 Garfield (295K), hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, early hits ignored
50/50 Garfield, resolution ch 20
50/50 Garfield, resolution vs hit radius
50/50 Garfield, resolution ch 20 for tracks of radius 5mm+


Max drift times from Garfield for 2090V, 295K
Ar(%) CO2(%) tmax(ns)
50.0 50.0 676
50.25 49.75 674
50.5 49.5 668
50.75 49.25 666
51.0 49.0 661

Try 50.5/49.5 to match tmax of 668 from drift time fit

Resolution for 2090V, 50/50 Garfield (295K), hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, early hits ignored
50/50 Garfield, resolution ch 20
50/50 Garfield, resolution vs hit radius
50/50 Garfield, resolution ch 20 for tracks of radius 5mm+
Resolution for 2090V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, 49.7/50.3 Garfield
50.5/49.5 Garfield, resolution vs track radius
50.5/49.5 Garfield, resolution vs track radius


Fit with sum of 2 gaussians

2090V 50.5/49.5 295K Garfield etc Resolution for np=17, tz_add=8ns, hits before t-zero reassigned
tfix = 1ns
tfix = 2ns
tfix = 3ns
tfix = 4ns
tfix = 5ns
tfix = 6ns


Resolution for 2090V, 50.5/49.5 Garfield (295K), hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, tfix=4
50.5/49.5 Garfield, resolution ch 20
50.5/49.5 Garfield, resolution vs hit radius
50.5/49.5 Garfield, resolution ch 20 for tracks of radius 5mm+
Resolution for 2090V, 50.5/49.5 Garfield (295K)hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, tfix=4
50.5/49.5 Garfield, resolution vs track radius
50.5/49.5 Garfield, resolution vs track radius


2100V - Check pedestal is ok and find MPV

2100V, 50/50 gas, prototype horizontal
Pedestal mean of samples 0-99, ch20, over 1 day
Pedestal std. dev. of samples 0-99, ch20, over 1 day
Max amplitude ch20, hit threshold 5sigma

2100V - Find best point to take as local pedestal

Find out where to take local pedestal. These are plots of change in ADC value vs time relative to the threshold crossing time.

2100V 50/50 Change in ADC value vs time relative to the threshold crossing time (in units of 8ns/5)
2090V, hit thr 5 ped-sigma

mean adc change 0.5 at -16.6 and 1 at -14

2100V - Fit drift time histogram and find t-zero

Drift time for 2100V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-16, tz_add=0
2090V, hit threshold 5sigma, time thresholds 4 and 1 sigma Estimate of t0 is 86.8 and tmax is 750.0, difference is 663, straight-line intercept is 79.97, to match histogram fit t0, use tz_add 6.86, diff between fit maximum and fit t0 is 4.26
Same, x-axis expanded
Same, x-axis expanded

2100V - Look at position resolution, find best gas mix for Garfield x-t tables

Max drift times from Garfield for 2100V, 295K
Ar(%) CO2(%) tmax(ns)
49.75 50.25 678
50.0 50.0 672
50.25 49.75 672
50.75 49.25 663


Resolution for 2100V, 50/50 Garfield (295K), hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-16, tz_add=7, early hits ignored
50/50 Garfield, resolution ch 20
50/50 Garfield, resolution vs hit radius
50/50 Garfield, resolution ch 20 for tracks of radius 5mm+


Resolution for 2100V, different gas mixes in Garfield (295K), hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-16, tz_add=7, early hits ignored
50.25/49.75 Garfield, resolution ch 20 for tracks of radius 5mm+
50.5/49.5 Garfield, resolution ch 20 for tracks of radius 5mm+
50.75/49.25 Garfield, resolution ch 20 for tracks of radius 5mm+


Resolution for 2100V, 50.25/49.75 Garfield (295K), hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-16, tz_add=7, early hits ignored
50.25/49.75 Garfield, resolution ch 20
50.25/49.75 Garfield, resolution vs hit radius
50.25/49.75 Garfield, resolution ch 20 for tracks of radius 5mm+
Resolution for 2100V, 50.25/49.75 Garfield (295K), hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-16, tz_add=7, early hits ignored (same as previous, updated tracking code)
50.25/49.75 Garfield, resolution ch 20
50.25/49.75 Garfield, resolution vs hit radius
50.25/49.75 Garfield, resolution ch 20 for tracks of radius 5mm+
Resolution for 2100V, 50.25/49.75 Garfield (295K), hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-16, tz_add=7, early hits ignored
50.25/49.75 Garfield, resolution vs track radius
50.25/49.75 Garfield, resolution vs track radius

2100V - Reassign pre-tzero hits

Include previously ignored hits which arrived before tzero+tz_add, assign these to a fixed drift time

2100V 50.25/49.75 Garfield etc Resolution for np=16, tz_add=7ns, hits before t-zero reassigned
tfix = 1000 (ignored), 0, 1ns
tfix = 1, 2, 3ns

Fit with sum of 2 gaussians

2100V 50.25/49.75 Garfield etc Resolution for np=16, tz_add=7ns, hits before t-zero reassigned
tfix = 1ns
tfix = 2ns
tfix = 3ns
tfix = 4ns
tfix = 5ns
tfix = 6ns
Resolution for 2100V, 50.25/49.75 Garfield (295K), hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-16, tz_add=7, tfix=2
50.25/49.75 Garfield, resolution ch 20
50.25/49.75 Garfield, resolution vs hit radius
50.25/49.75 Garfield, resolution ch 20 for tracks of radius 5mm+
Resolution for 2100V, 50.25/49.75 Garfield (295K)hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-16, tz_add=7, tfix=2
50.5/49.5 Garfield, resolution vs track radius
50.5/49.5 Garfield, resolution vs track radius