Response Function Measurements of the Self-TOF Neutron Detector for Neutrons up to 800 MeV

Abstract

The Self-TOF detector has been developed for high energy neutron spectrometry behind a shield. This detector consists of a radiator, a start counter and a stop counter. The radiator is composed of 20 thin plastic-scintillation detectors and the stop counter is segmented into nine plastic-scintillation detectors. The response functions of the Self-TOF detector for high energy neutrons up to 800 MeV were measured at the HIMAC (Heavy Ion Medical Accelerator in Chiba) of the National Institute of Radiological Sciences (NIRS). The measured responses were compared with those calculated using the LCS (LAHET Code System). The LCS results considerably overestimate the measuremental results with an increase in the neutron energy. It was found that this detector can give the neutron energy spectrum by using the FERDO-U unfolding code combined with the measured response functions, and is useful for high energy neutron spectrometry because of the almost constant efficiency for neutrons above 100 MeV.