Nondestructive Determination of Areal Density and Tritium Content of Tritided Erbium Films with Beta-Excited X-rays

The x-ray spectrum emitted from a tritided erbium film as a result of the beta decay is used to determine areal density and tritium content of the film. A Si (Li) detector and a dedicated minicomputer are used for detection, acquisition, and data reduction. The technique is suitable for areal densities of erbium from 0.01 mg/cm2 to as high as 10 mg/cm2. The occluded tritium can be measured from less than one to several hundred microliters. Precision is generally determined by counting errors and is typically less than 1% for a 5-min count while accuracy depends upon the empirical calibration technique.