The possibility of applications of characteristic X-rays from radioactive products of reactor neutron activation was investigated with particular emphasis on (n, ), n, n
), (n, 2n), (n, p) and (n,
) products with long half-lives. The sensitivity and detection limits of silver, cerium, gadolinium, selenium, cadmium and europium have been investigated. The elements were studied both in a pure and in a matrix form, in both cases the samples were diluted with graphite (
90%) to minimize matrix effects (absorption and enhancement).