Determination of Trace Elements in Samples by Nuclear Scattering and Reaction Techniques

The feasibility of using low energy (15-25 MeV) ??-particle scattering for detecting traces of heavy elements in a bulk of light elements as, for example, in biological and environmental matter is explored. These measurements can provide information on all the elements in the sample simultaneously. Heavy elements require good energy resolution (~10 keV) for definite identification while light elements can be identified even with very poor energy resolution (??100 keV). Results of some measurements on a fish sample are presented. Similarly sub-Coulomb (p,??) reactions are explored for measuring traces of very light elements in a bulk of heavy elements. Suitable choice of bombarding energy almost completely suppresses the contribution from the heavy element. Results of a measurement in a very pure Zr sample are presented.