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An electronic component used in photomultipliers, particle detectors, and electron microscopes, in which single electrons may produce a large current by inducing secondary emission of electrons when they strike an anode. Also called electron amplifier.
(General Physics) physics a device for amplifying and measuring a flux of electrons. Each electron hits an anode surface and releases secondary electrons that are accelerated to a second surface; after several such stages a measurable pulse of current is obtained
a vacuum tube in which the flow of electrons from the cathode is amplified by secondary emission.