Errors,PGAA, and metrology

Analytical chemists are scientific scavengers, using any available physical phenomenon to determine the composition of materials. Accuracy, unlike mere reproducibility, depends on understanding the measurement process, most usefully by stressing it until it bends. The use of neutron capture gamma rays for analysis involves some issues not encountered in conventional neutron activation analysis which, when understood, extend the utility and reinforce the value of nuclear methods of elemental analysis. These methods are being increasingly recognized as tools for SI-traceable metrology.