Nuclear Reaction Prompt Gamma-Ray Analysis

Abstract

Mineral analysis concerns earth materials which contain all the elements in the Periodic Table. There are many sensitive methods for laboratory analysis of minerals and ores. Neutron activation analysis (NAA), described in Chapter II, is one of the most widely used techniques. It is not applicable, however, to several important (mainly) light elements and should be complemented by other methods. Nuclear reaction induced gamma-ray methods come to help in these instances. Since nuclear reactions are nearly always accompanied by the emission of prompt gamma rays, methods based on the on-line detection of prompt gamma rays from nuclear reactions enable (at least in principle) the determination of any element contained in the sample. Neutron-capture prompt gamma activation analysis (PGAA) is the most accurate complementary method for bulk samples, whereas for thin layers or surfaces charged particle induced gamma-ray emission (PIGE) complements the very accurate and sensitive particle-induced X-ray emission (PIXE) method, based on X-ray detection, in that PIGE is more sensitive to light elements.