Neutron detector development and measurements around particle accelerators

Various neutron detectors for spectrometry, environmental dosimetry and personal dosimetry have been developed by our group. For high energy neutron spectrometry, spallation detectors of C and Bi, large plastic and NE-213 scintillators, self TOF detector have been used for neutron production and shielding experiments at several high energy accelerator facilities, ISIS of Rutherford Appleton Laboratory, UK, Two-mile Linac of Stanford Linear Accelerator Center, USA, HIMAC of National Institute of Radiological Sciences, Japan, and RCNP of Osaka University, Japan. The response functions of these detectors have been obtained by measurements and calculations. Thick target neutron yields produced from high-energy particles from protons to Xe ions have been summarized, together with shielding benchmark experiments through concrete and iron at these facilities. Neutron measurements over wide energy range including cosmic neutron field were done with Phoswich detector and Bonner sphere spectrometer. For environmental neutron dosimetry, two types of dose equivalent dosimeters, so-called rem counters, high-sensitive type and light-weight type, have been developed and for personal dosimetry, silicon semiconductor dosimeter has been developed for use in nuclear facilities. These dosimeters have good quality to give ambient and personal dose equivalents for neutrons in the mixed radiation fields. The outline of these works will be reviewed in this paper.