Operational Parameters

Table 1: Geometrical parameters

Dimension (L$\times$W$\times$T)	59.25"$\times$22.75"$\times$3"
Active Region	48.2"$\times$12"
Wire plane configuration	U,U',X,X',V,V'

Table 2: Operational parameters

Operation HV	1970 V
Threshold	3.0 V
Gas content	Argon/Ethane 50:50 mixture
Gas pressure:	$\sim16$ psi

The cathode foil planes and field wires are applied the same HVs. Each chamber has 4 HV input connectors, two for foil planes and two for field wires. The signals from sense wires goes into Nanometrics N277 cards for preamplifying and discriminating. There are 20 preamplifier cards for each chamber, 10 on one side and 10 on the other side of the chamber. These Nanometrics cards need both +5 and -5 power input. The voltages are supplied by two Acopian power supplies, for +5 V and -5 V respectively.

The working gas inside the chambers is Argon and Ethane 50:50 mixture. It also contains a small amount of (about 1%) alcohol vapor to prevent aging of the wire chamber. The gas is mixed in the outside gas shed. For detail information about Hall C gas system, Please refer to Hall C How-To: Drift Chamber Gas System.