Abstract: Based on the mechanisms of neutron production and reactions,neutron reference radiation fields are n,γ mixed fields,where the gamma component primarily originates from gamma rays accompanying neutron production and those generated by the interaction of neutrons with materials in the radiation field environment.This paper investigates the application of an energy-compensated Geiger-Müller(G-M) counter in n,γ mixed radiation fields.Using the Monte Carlo (MC) particle transport code MCNP,the energy response of the G-M counter was simulated,and experimental validation was conducted in a gamma reference radiation field.The validation demonstrated that the energy compensation scheme effectively suppresses the over-response in the low-energy region.Utilizing this energy-compensated G-M counter,the ambient dose equivalent of gamma radiation in laboratory radioactive nuclide neutron source fields was measured.This improves the parameters of the reference radiation field and provides support for addressing calibration issues arising from the gamma response characteristics of neutron instruments.

Key words: Geiger-Müller(G-M) counter, Monte Carlo(MC) simulation, Radioactive neutron source, Ambient dose equivalent