https://doi.org/10.1351/goldbook.R05048
A term embracing electromagnetic waves as well as fast moving particles. In @A00338@ the term usually refers to radiation emitted during a nuclear process (@R05083@, nuclear reaction, @N04229@, accelerators).
Source:
PAC, 1994, 66, 2513. (Nomenclature for radioanalytical chemistry (IUPAC Recommendations 1994)) on page 2523 [Terms] [Paper]