In vivo partial body activation analysis using filtered neutron beam.

A facility for in vivo prompt gamma-ray activation analysis using a filtered neutron beam from a mobile nuclear reactor is described. The low-power nuclear reactor with a thermal neutron absorber provides a maximum neutron flux of 11,000 neutron/cm2.s in the liquid phantom positioned on the surface of the irradiation plane; uniformity of the neutron flux inside the phantom with unilateral and bilateral irradiations is investigated. The elemental concentration of toxic mercury in a body organ is determined from a rapid diagnostic irradiation with minimal radiation doses as well as high sensitivity.