gas amplification detector

A detector that utilizes a phenomenon of electron avalanche.
When a strong electric field is applied to a core wire which is held in an inert gas atmosphere at a certain pressure, electrons are accelerated by the electric field and collide with gas molecules. Then, the gas molecules are ionized into molecular ions and electrons. The electrons generated by ionization collide with gas molecules repeatedly, and the number of electrons increases at an accelerated rate (causing electron avalanche).
The gas amplification detector utilizes the electron avalanche. For example, a gas flow detector is one of gas amplification detector, in which the incident X-rays are absorbed by the gasses and the primary electrons are generated, and the electrons are amplified by the electron avalanche effect and finally measured as an electron current.
Some electron detectors used for the LVSEM also utilize the electron avalanche. This kind of detector is called a low vacuum secondary electron detector (ESED or GSED).

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