Difference between revisions of "CDC 50 50"

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−
The later part of this page is 60/40 being used as a template for the 50/50. New stuff (50/50) is above the line.
 
−
 
 
50/50 Ar/CO<sub>2</sub> and cosmics, prototype horizontal
 
50/50 Ar/CO<sub>2</sub> and cosmics, prototype horizontal
 +
 +
<h4>Short runs for range of HV, check pedestal is ok and find MPV</h4>
  
 
{| border="0" cellpadding="2"  
 
{| border="0" cellpadding="2"  
Line 36: Line 36:
 
|[[Image:run_31809_thr5_fitamp20.png|thumb|x150px|Max amplitude ch20, hit threshold 5sigma ]]
 
|[[Image:run_31809_thr5_fitamp20.png|thumb|x150px|Max amplitude ch20, hit threshold 5sigma ]]
 
|}
 
|}
 +
 +
<h4>Fit max amplitude histograms and find optimal HV</h4>
  
 
Where to start the fit from.
 
Where to start the fit from.
Line 104: Line 106:
 
|122
 
|122
 
|}
 
|}
 +
 +
 +
 +
<h4>2090V - Find best point to take as local pedestal</h4>
  
 
Find out where to take local pedestal.  These are plots of change in ADC value vs time relative to the threshold crossing time.
 
Find out where to take local pedestal.  These are plots of change in ADC value vs time relative to the threshold crossing time.
−
Nothing to do with Garfield or tz_add but already have a good default in place (take pedestal at np=13 minisamples before threshold crossing) so small changes here are a fine tuning.
+
 
 
{| border="0" cellpadding="2"  
 
{| border="0" cellpadding="2"  
 
|+ 2090V  50/50 Change in ADC value vs time relative to the threshold crossing time (in units of 8ns/5)
 
|+ 2090V  50/50 Change in ADC value vs time relative to the threshold crossing time (in units of 8ns/5)
Line 112: Line 118:
 
|}
 
|}
 
Mean goes through 0.5 and 1 at -17.2 and -14.4 for thr=5sigma
 
Mean goes through 0.5 and 1 at -17.2 and -14.4 for thr=5sigma
 +
 +
<h4>Fit drift time histogram and find t-zero</h4>
  
 
{| border="0" cellpadding="2"  
 
{| border="0" cellpadding="2"  
−
|+ Drift time for 2090V, hit thresholds 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(t4sig)-17, tz_add=0  
+
|+ Drift time for 2090V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=0  
 
|[[Image:run_31809_np17_thr5_20.png|thumb|x350px|2090V, hit threshold 5sigma, time thresholds 4 and 1 sigma
 
|[[Image:run_31809_np17_thr5_20.png|thumb|x350px|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
 
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
Line 123: Line 131:
  
 
Max drift time according to Garfield is 663ns for 50/50 Ar/CO2, 671ns for 49.5/50.5, 678ns for 49/51.
 
Max drift time according to Garfield is 663ns for 50/50 Ar/CO2, 671ns for 49.5/50.5, 678ns for 49/51.
 +
 +
<h4>Tracking efficiency plot</h4>
  
 
{| border="0" cellpadding="2"  
 
{| border="0" cellpadding="2"  
−
|+ Resolution for 2090V, hit thresholds 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(t4sig)-17, tz_add=8, 50/50 Garfield
+
|+ Tracks/Triggers, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17  
−
|[[Image:run_31809_np17_tz8_res20.png|thumb|x250px|2090V, resolution ch 20]]
+
|[[Image:eff_hv_5050_Jun2012_tf88_tfix1000_np17.png|thumb|x250px| tzero=88ns, early hits ignored
−
|[[Image:run_31809_np17_tz8_resx20.png|thumb|x250px|2090V, resolution vs hit radius]]
+
]]  
−
|[[Image:run_31809_np17_tz8_res20_5mm.png|thumb|x250px|2090V, resolution ch 20 for tracks of radius 5mm+]]
+
|[[Image:eff_hv_5050_Jun2012_tf88_tfix4_np17.png|thumb|x250px| tzero=88ns, early hits reassigned to tzero+4ns
 +
]]  
 
|}
 
|}
 +
 +
 +
<h4>Look at position resolution, find best gas mix for Garfield x-t tables</h4>
 +
 +
Find gas mix which puts the mean residuals for the tracks with drift distance 5mm+ closest to zero
  
 
{| border="0" cellpadding="2"  
 
{| border="0" cellpadding="2"  
−
|+ Resolution for 2090V, hit thresholds 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(t4sig)-17, tz_add=8, 50/50 Garfield  
+
|+ Resolution for 2090V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, 50/50 Garfield  
−
|[[Image:run_31809_np17_tz8_xchunks.png|thumb|x250px|resolution vs hit distance]]
+
|[[Image:run_31809_np17_tz8_res20.png|thumb|x250px|50/50 Garfield, resolution ch 20]]
−
|[[Image:run_31809_np17_tz8_xchunks3.png|thumb|x250px|resolution vs hit distance]]
+
|[[Image:run_31809_np17_tz8_resx20.png|thumb|x250px|50/50 Garfield, resolution vs hit radius]]
 +
|[[Image:run_31809_np17_tz8_res20_5mm.png|thumb|x250px|50/50 Garfield, resolution ch 20 for tracks of radius 5mm+]]
 
|}
 
|}
  
 +
{| border="0" cellpadding="2"
 +
|+ Resolution for 2090V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, 49.7/50.3 Garfield
 +
|[[Image:run_31809_497503_np17_tz8_res20.png|thumb|x250px|49.7/50.3 Garfield, resolution ch 20]]
 +
|[[Image:run_31809_497503_np17_tz8_resx20.png|thumb|x250px|49.7/50.3 Garfield, resolution vs hit radius]]
 +
|[[Image:run_31809_497503_np17_tz8_res20_5mm.png|thumb|x250px|49.7/50.3 Garfield, resolution ch 20 for tracks of radius 5mm+]]
 +
|}
  
 +
{| border="0" cellpadding="2"
 +
|+ Resolution for 2090V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, 49.5/50.5 Garfield
 +
|[[Image:run_31809_495505_np17_tz8_res20.png|thumb|x250px|49.5/50.5 Garfield, resolution ch 20]]
 +
|[[Image:run_31809_495505_np17_tz8_resx20.png|thumb|x250px|49.5/50.5 Garfield, resolution vs hit radius]]
 +
|[[Image:run_31809_495505_np17_tz8_res20_5mm.png|thumb|x250px|49.5/50.5 Garfield, resolution ch 20 for tracks of radius 5mm+]]
 +
|}
  
 +
{| border="0" cellpadding="2"
 +
|+ Resolution for 2090V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, 50/50 Garfield
 +
|[[Image:run_31809_np17_tz8_xchunks.png|thumb|x250px|50/50 Garfield, resolution vs track radius]]
 +
|[[Image:run_31809_np17_tz8_xchunks3.png|thumb|x250px|50/50 Garfield, resolution vs track radius]]
 +
|}
  
 +
{| border="0" cellpadding="2"
 +
|+ Resolution for 2090V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, 49.7/50.3 Garfield
 +
|[[Image:run_31809_497503_np17_tz8_xchunks.png|thumb|x250px|49.7/50.3 Garfield, resolution vs track radius]]
 +
|[[Image:run_31809_497503_np17_tz8_xchunks8.png|thumb|x250px|49.7/50.3 Garfield, resolution vs track radius]]
 +
|}
  
−
<hr/>
 
−
The later part of this page is 60/40 being used as a template for the 50/50. New stuff (50/50) is above the line.
 
−
<hr/>
 
  
−
<div style="background-color:gray">
+
{| border="0" cellpadding="2"
 +
|+ Resolution for 2090V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, 49.5/50.5 Garfield
 +
|[[Image:run_31809_495505_np17_tz8_xchunks.png|thumb|x250px|49.5/50.5 Garfield, resolution vs track radius]]
 +
|[[Image:run_31809_495505_np17_tz8_xchunks8.png|thumb|x250px|49.5/50.5 Garfield, resolution vs track radius]]
 +
|}
  
−
This does not look nearly as good as 50/50 gas mix.
 
−
Resolution is calculated as fitted drift distance - measured (interpolated) distance, so it is positive when the measured drift time and distance are too small.
 
−
In this case they are slightly too small at small drift distance but too large at large drift distance. This could be a problem with the gas mix.  For reference, plot res vs distance for tz=5,7,and 0.
 
  
 +
<h4>Reassign pre-tzero hits</h4>
 +
 +
Include previously ignored hits which arrived before tzero+tz_add, assign these to a fixed drift time
  
 
{| border="0" cellpadding="2"  
 
{| border="0" cellpadding="2"  
−
|+ Resolution for 1975V, hit thresholds 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(t4sig)-13, tz_add=8, 60/40 Garfield
+
|+ 2090V 49.5/50.5 Garfield etc Resolution for np=17, tz_add=8ns, hits before t-zero reassigned
−
|[[Image:run_31842_res20_tz8_6040.png|thumb|x250px|1975V, resolution ch 20]]
+
|[[Image:run_31809_tfixmulti1.png|thumb|x250px|tfix = 1000 (ignored), 0, 1ns]]
−
|[[Image:run_31842_resx20_tz8_6040.png|thumb|x250px|1975V, resolution vs hit radius]]
+
|[[Image:run_31809_tfixmulti2.png|thumb|x250px|tfix = 1, 2, 3ns]]
 
|}
 
|}
−
Increasing tz_add to 8ns shifts the resolution up at earlier times but it hardly moves at later times.  This would probably have been obvious from the tz=0 data (below) where all the measured drift distances are too large.  "Measured" drift distances are actually interpolated from a table of distance calculated for a given gas mix and a range of time measurements.  So for this data I should use Garfield tables for a gas mix with slower drift velocity, ie less Ar.
 
  
 +
Fit with sum of 2 gaussians
 
{| border="0" cellpadding="2"  
 
{| border="0" cellpadding="2"  
−
|+ Resolution for 1975V, hit thresholds 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(t4sig)-13, tz_add=0, 60/40 Garfield
+
|+ 2090V 49.5/50.5 Garfield etc Resolution for np=17, tz_add=8ns, hits before t-zero reassigned
−
|[[Image:run_31842_res20_tz0_6040.png|thumb|x250px|1975V, resolution ch 20]]
+
|[[Image:run_31809_2gaus_tfix1.png|thumb|x250px|tfix = 1ns]]
−
|[[Image:run_31842_resx20_tz0_6040.png|thumb|x250px|1975V, resolution vs hit radius]]
+
|[[Image:run_31809_2gaus_tfix2.png|thumb|x250px|tfix = 2ns]]
 +
|[[Image:run_31809_2gaus_tfix3.png|thumb|x250px|tfix = 3ns]]
 +
|-
 +
|[[Image:run_31809_2gaus_tfix4.png|thumb|x250px|tfix = 4ns]]
 +
|[[Image:run_31809_2gaus_tfix5.png|thumb|x250px|tfix = 5ns]]
 +
|[[Image:run_31809_2gaus_tfix6.png|thumb|x250px|tfix = 6ns]]
 
|}
 
|}
  
  
−
Suspect total flow of 60sccm might be too low for the CO2 MFC.  Increase to 80sccm and repeat. Also try Garfield for different gas mixes and look at tmax.
 
−
Fitted Tmax was 573, edge is from 560 to 600ns. Garfield calcs give 560ns for 60/40, 573ns (ta-daa!) for 59/41, 588ns for 28/42 and 610ns for 57/43.
 
−
It's easiest to look at resolution far from the wire to find the best gas mix model. 
 
 
{| border="0" cellpadding="2"  
 
{| border="0" cellpadding="2"  
−
|+ Resolution for 1975V, drift time > 240ns (~approx 5mm), different gas mix in Garfield, same thresholds and pedestal as before, tz_add=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
−
|[[Image:run_31842_res20_5mm_6040_tz6.png|thumb|x250px|60/40]]
+
|[[Image:run_31809_497503_np17_tz8_tfix4_res20.png|thumb|x250px|49.7/50.3 Garfield, resolution ch 20]]
−
|[[Image:run_31842_res20_5mm_5941_tz6.png|thumb|x250px|59/41]]
+
|[[Image:run_31809_497503_np17_tz8_tfix4_resx20.png|thumb|x250px|49.7/50.3 Garfield, resolution vs hit radius]]
−
|[[Image:run_31842_res20_5mm_585415_tz6.png|thumb|x250px|58.5/41.5]]
+
|[[Image:run_31809_497503_np17_tz8_tfix4_res20_5mm.png|thumb|x250px|49.7/50.3 Garfield, resolution ch 20 for tracks of radius 5mm+]]
−
|[[Image:run_31842_res20_5mm_5842_tz6.png|thumb|x250px|58/42]]
+
|}
 +
 
 +
<hr/>
 +
 
 +
{| border="1px" cellpadding="2" style="border-style:solid;"
 +
|+ 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
 
|}
 
|}
  
 
{| border="0" cellpadding="2"  
 
{| border="0" cellpadding="2"  
−
|+ Resolution for 1975V, same thresholds and pedestal as before, tz_add=6ns, 58.5/41.5 Garfield
+
|+ 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
−
|[[Image:run_31842_res20_tz6_585_415.png|thumb|x250px|1975V, resolution ch 20]]
+
|[[Image:run_31809_500-500-295K-np17-tz8-tfix1000-res20.png|thumb|x250px|50/50 Garfield, resolution ch 20]]
−
|[[Image:run_31842_resx20_tz6_585_415.png|thumb|x250px|1975V, resolution vs hit radius]]
+
|[[Image:run_31809_500-500-295K-np17-tz8-tfix1000-resx20.png|thumb|x250px|50/50 Garfield, resolution vs hit radius]]
 +
|[[Image:run_31809_500-500-295K-np17-tz8-tfix1000-res20_5mm.png|thumb|x250px|50/50 Garfield, resolution ch 20 for tracks of radius 5mm+]]
 
|}
 
|}
  
−
Now look at timing.  Where to take local pedestal.  These are plots of change in ADC value vs time relative to the threshold crossing time.
+
 
−
Nothing to do with Garfield or tz_add but already have a good default in place (take pedestal at np=13 minisamples before threshold crossing) so small changes here are a fine tuning.
+
{| border="1px" cellpadding="2" style="border-style:solid;"
 +
|+ 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
 +
 
 
{| border="0" cellpadding="2"  
 
{| border="0" cellpadding="2"  
−
|+ 1975V 59/41 Garfield etc Change in ADC value vs time relative to the threshold crossing time (in units of 8ns/5)
+
|+ 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
−
|[[Image:run_31842_thr5_findpedpt.png|thumb|x250px|1975V, hit thr 5 ped-sigma]]
+
|[[Image:run_31809_505-495-295K-np17-tz8-tfix1000-res20.png|thumb|x250px|50/50 Garfield, resolution ch 20]]
−
|[[Image:run_31842_thr6_findpedpt.png|thumb|x250px|1975V, hit thr 6 ped-sigma]]
+
|[[Image:run_31809_505-495-295K-np17-tz8-tfix1000-resx20.png|thumb|x250px|50/50 Garfield, resolution vs hit radius]]
 +
|[[Image:run_31809_505-495-295K-np17-tz8-tfix1000-res20_5mm.png|thumb|x250px|50/50 Garfield, resolution ch 20 for tracks of radius 5mm+]]
 
|}
 
|}
−
Mean goes through 0.5 and 1 at -16.4 and -13.7 for thr=5sigma, -17.6 and -14.9 for thr=6sigma
 
  
 
{| border="0" cellpadding="2"  
 
{| border="0" cellpadding="2"  
−
|+ 1975V 58.5/41.5 Garfield etc Resolution for different local pedestal points, tz_add=6ns
+
|+ Resolution for 2090V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-17, tz_add=8, 49.7/50.3 Garfield
−
|[[Image:run_31824_tz6_npmulti.png|thumb|x250px|10, 15, and 20 points (1.6ns each) before hit threshold]]
+
|[[Image:run_31809_505-495-295K-np17-tz8-tfix1000-xchunks.png|thumb|x250px|50.5/49.5 Garfield, resolution vs track radius]]
−
|[[Image:run_31824_tz6_npmulti3.png|thumb|x250px|15, 16, and 17 points (1.6ns each) before hit threshold]]
+
|[[Image:run_31809_505-495-295K-np17-tz8-tfix1000-xchunks8.png|thumb|x250px|50.5/49.5 Garfield, resolution vs track radius]]
 
|}
 
|}
  
  
 +
 +
Fit with sum of 2 gaussians
 
{| border="0" cellpadding="2"  
 
{| border="0" cellpadding="2"  
−
|+ 1975V 58.5/41.5 Garfield etc Resolution for different local pedestal points, tz_add=7ns
+
|+ 2090V 50.5/49.5 295K Garfield etc Resolution for np=17, tz_add=8ns, hits before t-zero reassigned
−
|[[Image:run_31824_tz7_npmulti.png|thumb|x250px|10, 15, and 20 points (1.6ns each) before hit threshold]]
+
|-
−
|[[Image:run_31824_tz7_npmulti3.png|thumb|x250px|15, 16, and 17 points (1.6ns each) before hit threshold]]
+
|[[Image:run_31809_5050-4950-295K-np17-tz8-tfix1-2gaus.png|thumb|x250px|tfix = 1ns]]
 +
|[[Image:run_31809_5050-4950-295K-np17-tz8-tfix2-2gaus.png|thumb|x250px|tfix = 2ns]]
 +
|[[Image:run_31809_5050-4950-295K-np17-tz8-tfix3-2gaus.png|thumb|x250px|tfix = 3ns]]
 +
|-
 +
|[[Image:run_31809_5050-4950-295K-np17-tz8-tfix4-2gaus.png|thumb|x250px|tfix = 4ns]]
 +
|[[Image:run_31809_5050-4950-295K-np17-tz8-tfix5-2gaus.png|thumb|x250px|tfix = 5ns]]
 +
|[[Image:run_31809_5050-4950-295K-np17-tz8-tfix6-2gaus.png|thumb|x250px|tfix = 6ns]]
 
|}
 
|}
  
  
 
{| border="0" cellpadding="2"  
 
{| border="0" cellpadding="2"  
−
|+ Resolution for 1975V, 58.5/41.5 Garfield, hit thresholds 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(t4sig)-16, tz_add=7ns, tfix=1000
+
|+ 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
−
|[[Image:run_31842_585_415_thr5_np16_tz7_tfix1000_res20.png|thumb|x250px|1975V, resolution ch 20]]
+
|[[Image:run_31809_505-495-295K-np17-tz8-tfix4-res20.png|thumb|x250px|50.5/49.5 Garfield, resolution ch 20]]
−
|[[Image:run_31842_585_415_thr5_np16_tz7_tfix1000_resx20.png|thumb|x250px|1975V, resolution vs hit radius]]
+
|[[Image:run_31809_505-495-295K-np17-tz8-tfix4-resx20.png|thumb|x250px|50.5/49.5 Garfield, resolution vs hit radius]]
 +
|[[Image:run_31809_505-495-295K-np17-tz8-tfix4-res20_5mm.png|thumb|x250px|50.5/49.5 Garfield, resolution ch 20 for tracks of radius 5mm+]]
 
|}
 
|}
  
−
Now include previously ignored hits which arrived before tzero+tz_add, assign these to a fixed drift time
 
 
{| border="0" cellpadding="2"  
 
{| border="0" cellpadding="2"  
−
|+ 1975V 58.5/41.5 Garfield etc Resolution for np=16, tz_add=7ns, early hits assigned to 0ns, 1ns, 2ns
+
|+ 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
−
|[[Image:run_31824_tz7_tfixmulti.png|thumb|x250px|tfix = 0, 1, 2ns]]
+
|[[Image:run_31809_505-495-295K-np17-tz8-tfix4-xchunks.png|thumb|x250px|50.5/49.5 Garfield, resolution vs track radius]]
 +
|[[Image:run_31809_505-495-295K-np17-tz8-tfix4-xchunks8.png|thumb|x250px|50.5/49.5 Garfield, resolution vs track radius]]
 
|}
 
|}
 +
 +
 
   
 
   
 +
<h4>2100V - Check pedestal is ok and find MPV</h4>
 +
 +
{| border="0" cellpadding="2"
 +
|+ 2100V, 50/50 gas, prototype horizontal
 +
|[[Image:run_31942_pedmean.png|thumb|x150px|Pedestal mean of samples 0-99, ch20, over 1 day ]]
 +
|[[Image:run_31942_pedsig.png|thumb|x150px|Pedestal std. dev. of samples 0-99, ch20, over 1 day ]]
 +
|[[Image:run_31942_thr5_fitamp20.png|thumb|x150px|Max amplitude ch20, hit threshold 5sigma ]]
 +
|}
 +
 +
<h4>2100V - Find best point to take as local pedestal</h4>
 +
 +
Find out where to take local pedestal.  These are plots of change in ADC value vs time relative to the threshold crossing time.
 +
 +
{| border="0" cellpadding="2"
 +
|+ 2100V  50/50 Change in ADC value vs time relative to the threshold crossing time (in units of 8ns/5)
 +
|[[Image:run_31942_thr5_findpedpt.png|thumb|x250px|2090V, hit thr 5 ped-sigma]]
 +
|}
 +
mean adc change 0.5 at -16.6 and 1 at -14
 +
 +
<h4>2100V - Fit drift time histogram and find t-zero</h4>
 +
 +
{| border="0" cellpadding="2"
 +
|+ Drift time for 2100V, hit threshold 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(5sig)-16, tz_add=0
 +
|[[Image:run_31942_np16_thr5_dt20.png|thumb|x350px|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]]
 +
|[[Image:run_31942_np16_thr5_dt20z.png|thumb|x250px|Same, x-axis expanded]]
 +
|[[Image:run_31942_np16_thr5_dt20z2.png|thumb|x250px|Same, x-axis expanded]]
 +
|}
 +
 +
<h4>2100V - Look at position resolution, find best gas mix for Garfield x-t tables</h4>
 +
 +
{| border="1px" cellpadding="2" style="border-style:solid;"
 +
|+ 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
 +
|}
 +
 +
 +
{| border="0" cellpadding="2"
 +
|+ 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
 +
|[[Image:run_31942_50-50-295K-np16-tz7-tfix1000-res20.png|thumb|x250px|50/50 Garfield, resolution ch 20]]
 +
|[[Image:run_31942_50-50-295K-np16-tz7-tfix1000-resx20.png|thumb|x250px|50/50 Garfield, resolution vs hit radius]]
 +
|[[Image:run_31942_50-50-295K-np16-tz7-tfix1000-res20_5mm.png|thumb|x250px|50/50 Garfield, resolution ch 20 for tracks of radius 5mm+]]
 +
|}
 +
 +
 +
{| border="0" cellpadding="2"
 +
|+ 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
 +
|[[Image:run_31942_5025-4975-295K-np16-tz7-tfix1000-res20_5mm.png|thumb|x250px|50.25/49.75 Garfield, resolution ch 20 for tracks of radius 5mm+]]
 +
|[[Image:run_31942_5050-4950-295K-np16-tz7-tfix1000-res20_5mm.png|thumb|x250px|50.5/49.5 Garfield, resolution ch 20 for tracks of radius 5mm+]]
 +
|[[Image:run_31942_5075-4925-295K-np16-tz7-tfix1000-res20_5mm.png|thumb|x250px|50.75/49.25 Garfield, resolution ch 20 for tracks of radius 5mm+]]
 +
|}
 +
 +
 +
{| border="0" cellpadding="2"
 +
|+ 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
 +
|[[Image:run_31942_5025-4975-295K-np16-tz7-tfix1000-res20.png|thumb|x250px|50.25/49.75 Garfield, resolution ch 20]]
 +
|[[Image:run_31942_5025-4975-295K-np16-tz7-tfix1000-resx20.png|thumb|x250px|50.25/49.75 Garfield, resolution vs hit radius]]
 +
|[[Image:run_31942_5025-4975-295K-np16-tz7-tfix1000-res20_5mm.png|thumb|x250px|50.25/49.75 Garfield, resolution ch 20 for tracks of radius 5mm+]]
 +
|}
 +
 +
{| border="0" cellpadding="2"
 +
|+ 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)
 +
|[[Image:run_31942_tr127_5025-4975-295K-np16-tz7-tfix1000-res20.png|thumb|x250px|50.25/49.75 Garfield, resolution ch 20]]
 +
|[[Image:run_31942_tr127_5025-4975-295K-np16-tz7-tfix1000-resx20.png|thumb|x250px|50.25/49.75 Garfield, resolution vs hit radius]]
 +
|[[Image:run_31942_tr127_5025-4975-295K-np16-tz7-tfix1000-res20_5mm.png|thumb|x250px|50.25/49.75 Garfield, resolution ch 20 for tracks of radius 5mm+]]
 +
|}
 +
 +
{| border="0" cellpadding="2"
 +
|+ 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
 +
|[[Image:run_31942_tr127_5025-4975-295K-np16-tz7-tfix1000-xchunks.png|thumb|x250px|50.25/49.75 Garfield, resolution vs track radius]]
 +
|[[Image:run_31942_tr127_5025-4975-295K-np16-tz7-tfix1000-xchunks8.png|thumb|x250px|50.25/49.75 Garfield, resolution vs track radius]]
 +
|}
 +
 +
<h4>2100V - Reassign pre-tzero hits</h4>
 +
 +
Include previously ignored hits which arrived before tzero+tz_add, assign these to a fixed drift time
 +
 +
{| border="0" cellpadding="2"
 +
|+ 2100V 50.25/49.75 Garfield etc Resolution for np=16, tz_add=7ns, hits before t-zero reassigned
 +
|[[Image:run_31942_tfix_1000_0_1.png|thumb|x250px|tfix = 1000 (ignored), 0, 1ns]]
 +
|[[Image:run_31942_tfix_1_2_3.png|thumb|x250px|tfix = 1, 2, 3ns]]
 +
|}
 +
 +
Fit with sum of 2 gaussians
 +
{| border="0" cellpadding="2"
 +
|+ 2100V 50.25/49.75 Garfield etc Resolution for np=16, tz_add=7ns, hits before t-zero reassigned
 +
|[[Image:run_31942_2gaus_tfix1.png|thumb|x250px|tfix = 1ns]]
 +
|[[Image:run_31942_2gaus_tfix2.png|thumb|x250px|tfix = 2ns]]
 +
|[[Image:run_31942_2gaus_tfix3.png|thumb|x250px|tfix = 3ns]]
 +
|-
 +
|[[Image:run_31942_2gaus_tfix4.png|thumb|x250px|tfix = 4ns]]
 +
|[[Image:run_31942_2gaus_tfix5.png|thumb|x250px|tfix = 5ns]]
 +
|[[Image:run_31942_2gaus_tfix6.png|thumb|x250px|tfix = 6ns]]
 +
|}
  
 
{| border="0" cellpadding="2"  
 
{| border="0" cellpadding="2"  
−
|+ Resolution for 1975V, 58.5/41.5 Garfield, hit thresholds 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(t4sig)-16, tz_add=7ns, tfix=1ns
+
|+ 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
−
|[[Image:run_31842_585_415_thr5_np16_tz7_tfix1_res20.png|thumb|x250px|1975V, resolution ch 20]]
+
|[[Image:run_31942_5025-4975-295K-np16-tz7-tfix2-res20.png|thumb|x250px|50.25/49.75 Garfield, resolution ch 20]]
−
|[[Image:run_31842_585_415_thr5_np16_tz7_tfix1_resx20.png|thumb|x250px|1975V, resolution vs hit radius]]
+
|[[Image:run_31942_5025-4975-295K-np16-tz7-tfix2-resx20.png|thumb|x250px|50.25/49.75 Garfield, resolution vs hit radius]]
 +
|[[Image:run_31942_5025-4975-295K-np16-tz7-tfix2-res20_5mm.png|thumb|x250px|50.25/49.75 Garfield, resolution ch 20 for tracks of radius 5mm+]]
 
|}
 
|}
  
 
{| border="0" cellpadding="2"  
 
{| border="0" cellpadding="2"  
−
|+ Resolution for 1975V, 58.5/41.5 Garfield, hit thresholds 5sigma, timing thresholds 4sigma, 1sigma, pedestal at t(t4sig)-16, tz_add=7ns, tfix=2ns
+
|+ 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
−
|[[Image:run_31842_585_415_thr5_np16_tz7_tfix2_res20.png|thumb|x250px|1975V, resolution ch 20]]
+
|[[Image:run_31942_5025-4975-295K-np16-tz7-tfix2-xchunks.png|thumb|x250px|50.5/49.5 Garfield, resolution vs track radius]]
−
|[[Image:run_31842_585_415_thr5_np16_tz7_tfix2_resx20.png|thumb|x250px|1975V, resolution vs hit radius]]
+
|[[Image:run_31942_5025-4975-295K-np16-tz7-tfix2-xchunks8.png|thumb|x250px|50.5/49.5 Garfield, resolution vs track radius]]
 
|}
 
|}
−
</div>
 

Latest revision as of 15:58, 12 February 2013

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
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