Characteristics of two spherical 3He proportional counters

A 3He gas proportional counter is an ideal detector for thermal and epithermal neutron detection because of its high sensitivity. This kind of detector has been widely used in moderator-type neutron area monitors such as a Neutron Survey Meter or a Neutron Multisphere Spectrometer. The characteristics of two spherical 3He gas proportional counters with different gas pressures, have been determined in terms of their energy responses, their angular responses and their collimated beam responses. The results confirm that the 3He proportional counters have approximate 1/En1/2 energy responses and isotropic responses. (Author)