The Multiwire Chamber

How it Works

When a charged particle passes through a gas, it ionises the atoms. The atoms split into a negatively charged electron and a positively charged ion. In an electrical field the electrons will move towards the anode and the ions towards the cathode. In the high electric field around the thin anode wire the electrons will be accelerated and cause additional ionisations. The liberated electrons will, in their turn, cause additional electrons to be liberated, resulting in an avalanche of electrons close to the anode wire.

This avalanche of charges gives rise to an electric pulse on the anode wire, indicating the presence of the original particle.

Each anode wire can handle several hundred thousand signals per second. This is important when rare processes are studied and only a tiny fraction of the particle collisions is of particular interest.

The rings show the electric field around the anode wires.

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