From GlueXWiki
DRAFT Nominal Design Parameters for FDC
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Issue for CD-2?
Geometry:
For each chamber unit
Active volume inner radius: 3.5 cm
Active volume outer radius: 53.6 cm
Chamber assembly outer radius: 65 cm
Number of U cathode strips (50 micron Kapton, 5 micron Cu): 192
Number of W cathode strips (50 micron Kapton, 5 micron Cu): 192
Number of sense wires (20 micron gold-plated W): 96
Number of field wires (100 micron gold-plated Al): 97
x Gas (1 cm at 1 at.): Ar/CO2 85/15?
Number of cables (34-conductor shielded ribbon cables): 180
Pitch of cathodes: 5 mm?
Gap between strips: 1 mm
Positioning accuracy of sense wires (x,y): 10 microns?
Positioning accuracy of package (z): ?
x Number of chamber units per package: 6
x Thickness per package (cm): 12
x Thickness per package (g/cm2): 0.394
x Thickness per package (rad. lengths): 0.012
Thickness of inactive ring: 6.4 cm G10 (10.88 g/cm2) + 1 cm of cable
(0.88 g/cm2) per package = 11.76 - 14.40 g/cm2.
Location:
Package 1 (upstream face):...
Package 2 (upstream face):
Package 3 (upstream face):
Package 4 (upstream face):
dE/dX capability:
x Cathode strips: NO/YES
x Sense wires: NO/YES
Operation:
Nominal operating voltage (sense):...
Nominal operating voltage (field):....
Nominal gas gain: 10^5?
Gas flow: five volume change per day?
Preamplifier (nominal parameters):
Nominal gain: ?
Noise level: ?
rise time: ?
tail compensation: YES
Cable length to post-amp: 100 ft?
discriminator output: NO/YES?
Readout:
Cathode strips: 100 MHz FADCs
x Sense wires: 8.3 GHz pipeline TDCs
Calibration:
Cathode strips (selected charge): electronic pulser
Sense wires (selected charge): electronic pulser
Resolution:
Position resolution (sigma_U): 200 microns?
Position resolution (sigma_W): 200 microns?
Position resolution (sigma_x): 200 microns?
