APPARATUS AND METHOD FOR MEASURING BULK DENSITY USING POSITRON SCATTERING AND ANNIHILATION

摘要

A device for monitoring the bulk density and/or mass flow rate of a material within a vessel using positron scattering and annihilation radiometry techniques. The positron source is disposed on one side of the vessel having walls while an annihilation region preferably forming a portion of the vessel walls is disposed on the other side of the vessel. A gamma ray detector disposed externally of the vessel and collimated from the positron source detects the absorption of the positrons within the annihilation region. Monitoring the number of positrons absorbed within the annihilation region facilitates estimating bulk density and mass flow rates.