FDC Nominal Design Parameters

From GlueXWiki
Jump to: navigation, search

DRAFT Nominal Design Parameters for FDC
----------------------------------------

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?