Patent ID: 7010087

Claim:
A method of determining the density profile of material within a vessel comprising positioning a source of penetrating radiation having its characteristic energy level, or levels at above 700 keV adjacent said vessel at a first location, positioning a radiation detector adjacent said vessel in alignment with said source to detect radiation at at least one energy level in the range 80 keV to 700 keV that has passed through a portion of said material at said first location, determining the intensity and/or energy level of said radiation at said energy level within the range from 80 keV to 700 keV, moving said source and detector to a second location displaced from said first location and determining the intensity and/or energy level of said radiation at said at least one energy level in the range from 80 keV to 700 keV at said second location, and comparing the determined intensities and/or energy levels in the range from 80 keV to 700 keV and thereby determining the density of said material at said second location relative to its density at the first location.