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In particle physics there have been many devices used for tracking. These include cloud chambers (1920–1950), nuclear emulsion plates (1937–), bubble chambers (1952–), [ 3 ] spark chambers (1954-), multi wire proportional chambers (1968–) and drift chambers (1971–), [ 4 ] including time projection chambers (1974–).
The detection of charged particles within the chamber is possible by the ionizing of gas particles due to the motion of the charged particle. [14] The Fermilab detector CDF II contains a drift chamber called the Central Outer Tracker. [15] The chamber contains argon and ethane gas, and wires separated by 3.56-millimetre gaps. [16]
On one side of the detector is a high-voltage cathode plane, used to establish a drift electric field across the TPC. Although the exact electric potential at which this is set is dependent on the detector geometry, this high-voltage cathode typically produces a drift field of 500 V/cm across the detector. [10]
The drift tube (DT) system measures muon positions in the barrel part of the detector. Each 4-cm-wide tube contains a stretched wire within a gas volume. When a muon or any charged particle passes through the volume it knocks electrons off the atoms of the gas. These follow the electric field ending up at the positively charged wire.
There are two aspects of the muon detectors: the planar drift chambers and scintillators. There are four layers of planar drift chambers, each with the capability of detecting muons with a transverse momentum p T > 1.4 GeV/c. [9] These drift chambers work in the same way as the COT. They are filled with gas and wire.
Drift Chamber (DCH) Less expensive than silicon, the 40 layers of wires in this gas chamber detect charged particle tracks out to a much larger radius, providing a measurement of their momenta. In addition, the DCH also measures the energy loss of the particles as they pass through matter.
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A set of 1200 chambers measuring with high spatial precision the tracks of the outgoing muons; A set of triggering chambers with accurate time-resolution. The extent of this sub-detector starts at a radius of 4.25 m close to the calorimeters out to the full radius of the detector (11 m).