High count rates are desired because they produce small counting uncertainties. Lab C offers two types of count enhancing for moderated sensors:
(1) A new Li-core thermal neutron detector has 3.5 times the count rate of the COSMOS standard He-based sensor (both equipped with the standard 1-inch moderator).
(2) A new proprietary count enhancement technique [Patented technology] yields up to two times higher moderated neutron count rates from the same thermal neutron detector. For Li-core detector this factor is 1.3; for He-core detector it is 2; and for BF3 it is 1.6.
A new moderated sensor with Li-core thermal neutron detector (left side in the photo) has been constructed and is being tested against the standard He-core sensor (right side) at the Santa Rita Mesquite COSMOS site.
The side-by-side measurements conducted between December 2017 and March 2018 revealed that:
(1) The count rate of the new sensor is more than three times higher than that of the He-based system. Therefore, the uncertainty due to counting statistics is reduced by approximately a factor of 1.7. In the figure below it is manifested by smaller noise in the Li-core count data (top figure) and by lower coefficient of variation (bottom figure).
(2) The dynamic range of the Li-core sensor is almost identical to the standard He-core COSMOS sensor.
Application. The new Li-core moderated sensor is an excellent replacement for the He systems. The price of the Li-core sensor is comparable to that of the standard He-core sensor. Combined with other count-enhancing techniques, it yields an estimated nine-fold increase of the count rate, as compared with the standard COSMOS He-core sensor.
