moderator

https://doi.org/10.1351/goldbook.M03961
A material used to reduce the neutron energy by scattering without appreciable capture.
Source:
PAC, 1994, 66, 2513. 'Nomenclature for radioanalytical chemistry (IUPAC Recommendations 1994)' on page 2522 (https://doi.org/10.1351/pac199466122513)