photomultiplier

American  

[foh-tuh-muhl-tuh-plahy-er] / ˌfoʊ təˈmʌl təˌplaɪ ər /

noun

1. an extremely sensitive detector of light and of other radiation, consisting of a tube in which the electrons released by radiation striking a photocathode are accelerated, greatly amplifying the signal obtainable from small quantities of radiation.

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photomultiplier British  

/ ˌfəʊtəʊˈmʌltɪˌplaɪə /

noun

1. a device sensitive to electromagnetic radiation, consisting of a photocathode, from which electrons are released by incident photons, and an electron multiplier, which amplifies and produces a detectable pulse of current

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photomultiplier Scientific  

/ fō′tō-mŭl′tə-plī′ər /

1. An electrical device designed for the detection of weak electromagnetic radiation, usually light, by amplifying the energy of the photons that strike it into stronger electrical signals. Photomultipliers are used in night-vision technology and in telescopes to detect light not strong enough to be visible by the unaided eye.

2. ◆ The most common photomultiplier is the tube photomultiplier; it exploits secondary emission of electrons in a vacuum tube in the manner of an electron multiplier. When radiation strikes the cathode of a tube photomultiplier, electrons called photoelectrons are emitted and attracted to positively charged electrodes called dynodes. When they collide with the dynode, more electrons are released; these are in turn attracted to another dynode at a higher voltage to release yet more electrons, and so on. At the end of this process, there is a current flow at the anode that is strong enough to be easily detected.

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Etymology

Origin of photomultiplier

First recorded in 1935–40; photo- + multiplier

Example Sentences

The photons are captured by a detector, which in this case is essentially a cylindrical crystal with a photomultiplier tube that passes the light signal to the data acquisition system.

From Science Daily • Feb. 26, 2024

And industrial partners boosted the sensitivity of the 43,000 photomultiplier tubes arrayed around the sphere that detect the pulses.

From Science Magazine • Aug. 22, 2023

Then they tracked the resulting annihilation radiation at the farthest edges of their experiment, using two photomultiplier tubes, anthracene crystals and a scintillation counter as a gamma-ray detector.

From Scientific American • Mar. 16, 2023

IceCube, an international observatory run by 300 scientists from 12 countries, consists of more than 5,000 sensitive photomultiplier tubes embedded in grid encompassing a cubic kilometer of ice at the South Pole.

From New York Times • Jul. 12, 2018

The tube is equipped with a mounting bezel to accept a camera or photomultiplier device.

From Preliminary Specifications: Programmed Data Processor Model Three (PDP-3) October, 1960 by Digital Equipment Corporation