activation analysis(redirected from activation analyses)
Also found in: Dictionary, Encyclopedia.
the identification and quantification of unknown elements from their characteristic emissions and decay constants after they have been made radioactive by exposure to neutron or charged particle radiation.
neutron activation analysisA method for identifying and measuring the concentrations of the chemical elements in a large and complex sample of material.
A sample is rendered radioactive by bombarding it with neutrons, charged particles or gamma rays, making the nuclei of the different elements unstable and radioactive, and putting them in a higher energy state. Each of the now-radioactive isotopes in the sample gives off a characteristic signature (e.g., alpha particles, gamma rays), which indicates the type and concentration of the elements in the sample.