Neutron efficiency and gamma rejection performance of CLYC and He alternative technologies

A great deal of scientific research in recent years has focused on alternative neutron detection technologies to the more commonly used
³
He proportional counter. One such example is a novel thermal neutron detector developed by Los Alamos National Laboratory consisting of multiple thin film
¹⁰
B layers combined with a double helix electrode configuration. The detector promises low manufacturing costs and is designed to fit into an existing high density polyethylene moderator housing used by two standard 2 bar
³
He proportional counters, making this a potential direct replacement for many current portal scanning modules. Also of interest is the dual neutron-gamma detector Cs
₂
LiYCl
₆
(CLYC), which has the ability to discriminate between thermal neutron, fast neutron and gamma interactions and has a gamma spectroscopic performance surpassing common alkali-halide scintillators such as NaI(Tl). In this work a calibrated neutron facility was used to measure the intrinsic neutron detection efficiency of the detectors when exposed to
²⁵²
Cf and the gamma rejection performance when the detectors were exposed to two
¹³⁷
Cs sources. The subsequent results were compared to a commercially available
³
He detector module measured in the same experimental setup.