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Neutron flux from linear accelerators is conventionally monitored using ionization chambers containing one or
more foils thinly coated with a fissionable or fissile material. Due to the long pulse rise times resulting from the
ionization mechanism, fission chambers are prone to pulse pile-up in high-neutron-flux environments. In addition,
their relatively low efficiencies result in extremely long counting times in low-flux environments. To ameliorate
these effects, a novel type of neutron flux monitor, consisting of fissionable material loaded in a liquid scintillator,
has been developed, characterized, and tested in the beam line at the Los Alamos Neutron Science Center. This
is a rugged, cost-efficient detector with high efficiency, a short signal rise time, and the ability to be used in low
neutron-flux environments. Compared with a conventional fission chamber, the fissionable scintillator displays a
significantly higher event rate. Related research on nanocomposite scintillators for gamma-ray detection suggests
the possibility of extending this approach by synthesizing fissionable material nanoparticles and loading them
into an organic scintillator. We will present results of the design and characterization process and an analysis of
the results of the beam line experiments.
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