The multiwire chamber

This proportional chamber has five parallel planes of anode wires. The orientation of the almost invisible anode wires is best seen at the ends of the five light beams. Thanks to wire planes with different orientation the position of the passing particle can be determined very precisely.

Charpak's invention was the multiwire proportional chamber, where each wire acts as a detector. The important breakthrough was mainly due to the enormous increase in data-taking rate. The signals from the wires are recorded by computers that can handle large data flows.

Charpak realised from the beginning that there were several ways to further develop the multiwire chamber. The most important development was the drift chamber. This is used to measure the time taken for liberated electrons to drift to the anode. In this way precision was further improved.
    The multiwire chamber – both the proportional chamber and the drift chamber – is now in use in practically every experiment in particle physics laboratories. These detectors are also used in medicine as a complement to X rays.

A cylindrical drift chamber –
ideal for determining the tracks
of particles produced in
particle colliders.