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.
HeinrichK. F. J., Quantitative Electron Probe Analysis, Proceedings of a Seminar held at the National Bureau of Standards, Gaitherburg, Md., 12–13 June 1967, National Bureau of Standards Special Publication 298 (U.S. Government Printing Office, Washington, D.C., 1968).
2.
LiebhafskyH. A.PfeifferH. G.WinslowE. H., and ZemanyP. D., X-Ray Absorption and Emission in Analytical Chemistry (Wiley, New York1960), Chaps. 6–7.
