Title: pile-up
Long Title: IUPAC Gold Book - pile-up
DOI: 10.1351/goldbook.P04673
Status: current

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
- radiation detector: https://goldbook.iupac.org//terms/view/R05054
- spectrometer: https://goldbook.iupac.org//terms/view/S05837

Sources
- Orange Book, 2nd ed., p. 235 (https://media.iupac.org/publications/analytical_compendium/)
- PAC, 1994, 66, 2513. 'Nomenclature for radioanalytical chemistry (IUPAC Recommendations 1994)' on page 2523 (https://doi.org/10.1351/pac199466122513)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/P04673/html
- json: https://goldbook.iupac.org/terms/view/P04673/json
- xml: https://goldbook.iupac.org/terms/view/P04673/xml

Citation: 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. 10.1351/goldbook.P04673
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Accessed: 2025-10-29T15:19:40+00:00