Thermal neutron detection using pyroelectric ceramics together with boron converters

A method for detecting thermal neutrons using pyroelectric ceramics is described. The detector system consists of a commercially available PZT (lead zirconate titanate) ceramic disk, silvered on both faces to provide electrical contact, a pellet of boron converter to induce the temperature variation in the ceramic through the energy released in the 10B(n, α)7Li reaction, and an appropriate pulse amplifier system for amplification and stabilization of the signal generated by the detector. Two types of H3BO3 converters have been employed: one with natural isotopic abundance and another with 92.41% enrichment in 10B isotope. In our application two different neutron spectra extracted from the BH-3 and BH-8 beam tubes of the IEA-R1 reactor have been used. The signal amplitude obtained with this detector system has shown to be proportional to the 10B enrichment of the boron converters and remarkably linear with the thermal neutron flux within the calibration interval from 1.8x106 to 1.0x104 n/cm2s. (orig.)