A ¹²⁴Sb-Be Source of Thermal Neutrons for Precision Analysis and Tracer Production

An improved ¹²⁴Sb-Be neutron source was developed to give a thermal flux of 6 × 10⁸ n/(cm² sec) over a 20-cm³ volume with a uniformity better than ±4%. With a unit of this type, 90 radioisotopes with a specific activity of 0.1 µC/g can be produced. Because of the constancy of the flux, an analytical precision of ±1% is easily attainable. The present system will handle more than one sample transfer unit, allowing several simultaneous experiments or analyses. The pool system described here is a versatile research unit and not a general-purpose industrial analytical facility. Considering the features and costs of this ¹²⁴Sb-Be source, it appears best suited for applications requiring a continuous thermal-neutron flux, such as an on-line system for industry.