A new neutron detector based on ceramic THGEM and boron-coated meshes

Abstract

Boron-coated micro-pattern gaseous detectors, such as gaseous electron multiplier (GEM), are widely studied as the neutron detectors. The existing solution to improve the neutron detection efficiency (NDE) is to coat the boron on the surfaces of the cascade GEM films. So the GEM films themselves will be affected by the complicated coating process and the boron layers, and the $$^{10}$$ B material will be wasted once the GEM films are damaged. Since the neutron conversion and the electron multiplication regions are not separated, the final gains of different layer ionized electrons are very difficult to control and keep consistent. A new neutron detector based on the ceramic thick GEM (THGEM) was proposed. The boron-coated cathode and multilayer meshes were used as the neutron conversion region and separated from the electron multiplication region consisting of only one THGEM film. The sawtooth surface treatment and the double-sided readout method were applied to improve neutron conversion efficiency (NCE). The neutron conversion and the electron collection efficiencies were simulated and studied based on the new structure. The prototype detector was test by using a $$^{252}$$ Cf neutron source. The simulation results show that the cascade boron-coated meshes have good neutron conversion and electron collection efficiencies, and the double-sided readout and sawtooth structure can greatly increase the NCE. The neutron test results show that the detection efficiency of the double-sided readout is 1.6 times higher than that of the common single-sided readout. These indicate that the new detector has high neutron conversion and detection efficiencies and is promising for practical applications.