Difference between revisions of "Resolutions"

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| Distance from wire [mm]
 
| Distance from wire [mm]
−
colspan="2"| Resolution (low) [um]  
+
!colspan="2"| Resolution (low) [um]  
−
colspan="2"| Resolution (high [um]
+
!colspan="2"| Resolution (high [um]
 
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| 200 MHz
 
| 200 MHz
 
|-
 
|-
 +
| 0-1
 +
| 388
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| 394
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| 404
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| 396
 +
|-
 +
| 1-2
 +
| 346
 +
| 292
 +
| 346
 +
| 205
 +
|-
 +
| 2-3
 +
| 209
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| 191
 +
| 222
 +
| 210
 +
|-
 +
| 3-4
 +
| 142
 +
| 135
 +
| 166
 +
| 165
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|-
 +
| 4-5
 +
| 118
 +
| 96
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| 164
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| 151
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|-
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| 5-6
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| 85
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| 88
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| 148
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| 164
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|-
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| 6-7
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| 67
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| 70
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| 165
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| 174
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|-
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| 7-8
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| 65
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| 63
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| 158
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| 169
 
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Revision as of 13:50, 10 July 2009

Prelude

  • Two gases are used: 70/30 and 90/10 Ar/CO2
  • Two fADC clock settings are used: 125 and 200 MHz
  • Drift time spectra (DCOG method is used):
90/10 Ar/CO2 drift time spectra.
70/30 Ar/CO2 drift time spectra.
  • Red line is fit to get absolute minimal drift time
    • Best tracking results if extracted minimal drift time + 1 time sample
  • Samples per rising edge - 2 extra samples 125 -> 200 MHz
Samples/rising edge - 70/30 Ar/CO2 - 125~MHz clock.
Samples/rising edge - 70/30 Ar/CO2 - 200~MHz clock.
  • Time-2-distance relation:
    • GARFIELD is used. To get best resolutions out of it:
      • 68/32 Ar/CO2 is put in GARFIELD for 70/30 gas
      • 89/11 Ar/CO2 is put in GARFIELD for 90/10 gas
      • +-6% CO2 can give 100~ns difference


Resolutions

  • Difference in gases - blue line is a model prediction:
Resolutions (in um) as a function of distance to the wire (in mm) for 70/30.
Resolutions (in um) as a function of distance to the wire (in mm) for 90/10.
  • 90/10 worse because shorter drift times.
  • Model contains:
    • Timing resolution
    • accuracy
    • diffusion
Distance from wire [mm] Resolution (low) [um] Resolution (high [um]
125 MHz 200 MHz 125 MHz 200 MHz
0-1 388 394 404 396
1-2 346 292 346 205
2-3 209 191 222 210
3-4 142 135 166 165
4-5 118 96 164 151
5-6 85 88 148 164
6-7 67 70 165 174
7-8 65 63 158 169
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