How does a Geiger-Muller tube work?

When ionizing radiation passes through the tube, some of the gas molecules are ionized, creating positively charged ions, and electrons. The strong electric field created by the tube's electrodes accelerates the ions towards the cathode and the electrons towards the anode. The ion pairs gain sufficient energy to ionize further gas molecules through collisions on the way, creating an avalanche of charged particles.

This results in a short, intense pulse of current which passes (or cascades) from the negative electrode to the positive electrode and is measured or counted.

Most detectors include an audio amplifier that produce an audible click on discharge. The number of pulses per second measures the intensity of the radiation field. Some Geiger counters display an exposure rate (e.g. mR·h), but this does not relate easily to a dose rate as the instrument does not discriminate between radiation at different energy

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Geiger Muller Tube

Sealed tube with a thin window at one end which allows radioactive particles or rays to enter.

Reduced pressure. Special gas. Central electrode at high voltage.

Entering particle ionise the gas, these are attracted to the anode or cathode. On the way they hit others and ionise them. You get a cascade making a signal large enough to detect. This is fed into an amplifier and speaker to give the click associated with a GM tube.

hard can't explain soz

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