Description
A proportional counter uses a wire, under high voltage, which runs through a metal or conductive enclosure whose walls are held at ground potential. The enclosure is filled with carefully chosen gas, such as an argon/methane mix, such that any ionizing particle that passes through the tube will ionize surrounding gaseous atoms. The resulting ions and electrons are accelerated by the electric field around the wire, causing a localised cascade of ionization which is collected on the wire and results in an electric current proportional to the energy of the detected particle. This allows the experimenter to count particles and importantly, in the case of the proportional counter, to determine their energy.
Adaptions of design are the thin gap, resistive plate and drift chambers. The drift chamber is also sub-divided into ranges of specific use in the chamber designs known as time projection, microstrip gas, and those types of detectors that use silicon.
Read more about this topic: Wire Chamber
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