A neutron detector capable of measuring the timehyphen;dependent yield of 14hyphen;MeV neutrons from a Dndash;D plasma producing predominantly 2.5hyphen;MeV neutrons has been developed. The detector consists of a thick polythene recoil proton radiator backed by a graphite foil attached to a large area totally depleted ionhyphen;implanted diode. Protons scattered in the forward direction by 14hyphen;MeV neutrons pass through the graphite foil and are registered in the diode. Recoil protons from 2.5hyphen;MeV neutrons, however, are prevented from reaching the diode by the foil. When operated with a 1.5hyphen;MeV energy bias, the measured neutron detection efficiency for 15hyphen;MeV neutrons is 3.2times;10minus;3per neutron. The corresponding figure for 3.1hyphen;MeV neutrons is a factor of 540 lower. The neutron detector and its laboratory calibration are described, as is its deployment at the Joint European Torus where it serves as a triton burnhyphen;up monitor.
展开▼
