Difference between revisions of "Forward Drift Chamber Shift"
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== Routine operation== | == Routine operation== | ||
| + | The most important task for the shift workers is to monitor the environmental conditions | ||
During routine operation the user will need to monitor the environmental conditions, which may affect BCAL performance, as well as turn the | During routine operation the user will need to monitor the environmental conditions, which may affect BCAL performance, as well as turn the | ||
system on and off. The following instructions are for non-experts during routine operation.<font color=red> Operations beyond what is specified here shall only be performed by the system expert or under his/her direction. </font> If the expert directs an operation outside the ones described here, a specific note must be entered into the log book. | system on and off. The following instructions are for non-experts during routine operation.<font color=red> Operations beyond what is specified here shall only be performed by the system expert or under his/her direction. </font> If the expert directs an operation outside the ones described here, a specific note must be entered into the log book. | ||
Revision as of 16:06, 2 June 2014
The Forward Drift Chambers
The Forward Drift Chamber (FDC) system consists of four identical packages, each having six chambers (cells). These are planar drift chambers with both wire and cathode strips being readout, in total 12,672 channels.
The cells within a package have independent gas volumes, but are separated with a flexible mylar membrane and therefore the pressure difference between the cells should never exceed 30~Pa .
Positive (up to 2200V) and negative (up to 500V) HV is applied on the sense and field wires respectively with dark currents not exceeding 3 microA per HV channel .
The detector (including cables) emits a total power of about 1500~Watt, of which about 900~Watt inside the magnet, due to the LV applied on the detector pre-amplifieres. A cooling system using Fluorinert is used to keep the temperature on the pre-amplifiers within the permissible limits. The LV system should never be turned on if the cooling system doesn't work .
