Novel neutron spectroscopy and neutron monitoring using position sensitive detector

Neutron spectrometry is carried out using various methods, whereas the Bonner sphere method is widely used. The wide range of neutron energy measurements need to use multiple moderator spheres enclosing a neutron counting detector. We introduce the development of a novel type of neutron energy spectrometer using a high efficiency, one-dimensional position sensitive detector (PSD) and a cone shaped single moderator structure. This device is portable and useful to record data simultaneously. Such operations for rarely occurring events are not possible with multisphere device. Two different moderator structures with symmetrical and non-symmetrical shapes of variable thicknesses over the sensitive length of the PSD are designed and will be optimized for the best energy resolution. The neutron response along the PSD position is recorded using the compact module for pulse processing and digital division with an FPGA. The PSD response as a function of moderator thickness and neutron energy is observed for various neutron sources. We present the design concept of the spectrometer and results of the measurements carried out at DT neutron generator and using an AmF source. Neutron transmission and moderation data is simulated using the GEANT4 code. The measured data and energy response function is proposed to be used for the measurement of the neutron energy spectrum. (c) 2008 Elsevier B.V. All rights reserved.