Difference between revisions of "Forward Drift Chamber Shift"

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== The Forward Drift Chambers ==
 
== The Forward Drift Chambers ==
  
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The Forward Drift Chamber (FDC)  system consists
 
The Forward Drift Chamber (FDC)  system consists
 
of four identical packages, each having six chambers (cells).
 
of four identical packages, each having six chambers (cells).
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The chambers within a package
 
The chambers within a package
have independent gas volumes, but are separated with a flexible mylar membrane.
+
have independent gas volumes, but are separated with a flexible mylar membrane
 +
and therefore '''the pressure difference between the chambers should never exceed 30~Pa'''.  
 
Positive (up to 2200V) and negative (up to 500V) HV is applied on the
 
Positive (up to 2200V) and negative (up to 500V) HV is applied on the
 
sense and field wires respectively with currents
 
sense and field wires respectively with currents
 
not exceeding 3 $\mu $A per HV channel.
 
not exceeding 3 $\mu $A per HV channel.
 +
 
The detector (including cables) emits a total power of about 1500~Watt,
 
The detector (including cables) emits a total power of about 1500~Watt,
 
of which about 900~Watt inside the magnet,
 
of which about 900~Watt inside the magnet,
due to the LV applied on the detector pre-amplifieres;
+
due to the LV applied on the detector pre-amplifieres.
a cooling system using Fluorinert is used to keep the temperature on the
+
A cooling system using Fluorinert is used to keep the temperature on the
 
pre-amplifiers below ~50$^0$~C.
 
pre-amplifiers below ~50$^0$~C.
 +
 +
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== Routine operation==
 
== Routine operation==

Revision as of 14:56, 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 chambers within a package have independent gas volumes, but are separated with a flexible mylar membrane and therefore the pressure difference between the chambers 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 currents not exceeding 3 $\mu $A 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 below ~50$^0$~C.