Comparison of the fast-neutron sensitivity of a Geiger-Muller counter using different techniques

The sensitivity of an energy-compensated Geiger-Müller counter to neutrons with approximate energies of 0.6, 5 and 15 MeV, relative to its sensitivity to gamma rays (kU-value), has been determined at different centres in Europe. The time-of-flight, angular difference, associated-particle coincidence and lead filtration technique have been compared, using the same Geiger-Müller counter. For 15 MeV neutrons, a consistent kU-value of 1.9% was obtained. For the lower neutron energies, lower kU values were observed with reasonable agreement.