Nonintrusive local density determination using gamma scattering or neutron activation

Nonintrusive local density measurements can be made with radiation scattering densitometers having two radiation sources and two detectors. Published applications of scattering either require instrumentation movement or render the density field solution by differentiation or integration of measured functions. This paper describes how both local density values along one line and line-average density values lateral to the line can be determined simultaneously throughout the unknown density field, employing stationary instrumentation and algebraic equations only