Understanding Neutron Radiography Post Exam Reading VIII-Part 2a of 2A

Scintillation
Scintillators containing lithium-6, boron-10 and hydrogenous plastics have
been used as neutron detectors. Lithium-6 is used as lithium iodide (europium
activated) and in lithium glasses to detect slow and fast neutrons. Scintillators
loaded with boron-10 are used for slow neutron detection. Plastic scintillators
with high hydrogen content are used in fast neutron detection and
spectroscopy by measuring the energy deposited by recoil protons.
Activation Foils Introducing certain materials to an incident neutron flux will
result in these materials becoming radioactive. The process is called
activation and gaining information about the incident neutron flux and energy
is possible by analyzing the radiations emitted from the activated foil.
Activation foils rely on (n, γ), (n, p), (n, α), (n, f ) and other nuclear reactions
to cause the activation. Selection of the proper activation foil can give a rough
estimate of the neutron energy spectrum. In high neutron flux fields, where
instruments would fail, activation foils are used as integrating detectors.
Charlie Chong/ Fion Zhang