Application of a single crystal chemical vapor deposition diamond detector for deuteron plasma neutron measurement

A single crystal chemical vapor deposition (scCVD) diamond detector has been characterized and employed for the neutron measurement at the HL-2A tokamak device. The scCVD diamond detector has been deposited with 5μm of lithium fluoride (LiF) layer to enhance the sensitivity to thermal neutrons. Time stability of the detector has been studied with α-source and good performance has been found for more than 12h. Neutron irradiations have been performed in four quasi-monoenergetic neutron fields in the energy range from 2.50MeV to 16.03MeV. The measured response function of the scCVD diamond detector to 14.13MeV neutrons shows a narrow 12C (n, α)9Be reaction peak which is well isolated from other structures by about 1MeV in energy, indicating the great potential as a fast neutron spectrometer. Neutron measurement of deuterium plasma discharge was established at the HL-2A tokamak device, and good consistence has been revealed among this detector signal and other related signals.