Six horizontal beamports and a tangential thru-tube are available for long term irradiation and neutron beam extraction experiments such as neutron radiography and neutron spectroscopy. The horizontal beamports penetrate the reactor pool wall and terminate at the face of the core. A thermal column made of a stack of 5'x5'x10' graphite with a central radial beam hole is available for irradiations. The material is first made radioactive by bombardment with suitable nuclear particles, then the radioactive isotopes are identified and the element concentrations are determined from the gamma-rays they emit. The energy of the detected gamma-rays identifies the radioactive isotope, and the area of the resulting photopeak is proportional to its concentration.
Neutron activation is a very sensitive method of chemical analysis.
Sixty-seven elements become radioactive when bombarded with neutrons, and more than fifty of these elements can be identified and measured quite readily. The technique is paricularly useful for analyzing environmental and industrial samples to maintain quality control. The sensitivity and accuracy of the technique, the variety of materials that can be analyzed, the large number of elements that can be detected, and its essentially non-destructive nature make neutron activation analysis an outstanding analytical tool. If even lower detection limits are required, laboratory methods for radiochemical separations can be used. The Rhode Island Nuclear Science Center is well equipped to conduct neutron activation analysis.