ENERGY-SENSITIVE FAST NEUTRON IMAGING DETECTOR AND METHOD FOR ENERGY-SENSITIVE FAST NEUTRON DETECTION

摘要

An energy-sensitive imaging detector for fast-neutrons includes:
a) a series of energy-selective stacks (4 to 14 to 18) of radiator foils (6) which converts neutrons (n) into recoil protons (p, p1 to p3); said foils (6) are separated by gas-filled gaps (13) and are made of two layers fastened together: a hydrogen-rich layer, such as a polyethylene layer (10) for neutron-to-proton conversion, and a metal foil layer, such as an aluminum layer, defining a proton energy cut-off and limiting angle of proton emission;
b) surrounding gas in the gas-filled gaps (13) in which energetic recoil protons emerging from the radiator foil release electrons;
c) an electric field (E drift ) able to efficiently drift the electrons (20) through the gas-filled gaps (13); and
d) an electron detector with a position sensitive readout (PSRO), based on Micro-Pattern Gaseous Detector (MPGD) technologies (like e.g. the THick Gaseous Electron Multipliers - THGEM) or other means of electron amplification in gas; the charge detector is equipped with a dedicated imaging data-acquisition system, which detect the drifted electrons thereby sensing the position of the original impinging neutrons.