Term: pile-up
https://doi.org/10.1351/goldbook.P04673

Definition:
The processing by a radiation spectrometer of pulses resulting from the simultaneous adsorption of independent particles or photons in a radiation detector. As a result they are counted as one single particle or photon with energy between the individual energies and the sum of these energies.

Related Terms:
1) spectrometer (http://doi.org/10.1351/goldbook.S05837).
2) radiation detector (http://doi.org/10.1351/goldbook.R05054).

Source: Orange Book, 2nd ed., p. 235 (https://media.iupac.org/publications/analytical_compendium/)

Citation: 'pile-up' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.P04673

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