NEUTRON ACTIVATION ANALYSIS OF OXYGEN IN BERYLLIUM

Since it was difficult to measure trace quantities of oxygen in beryllium by chemical methods activation analysis was tried in an attempt to develop a satlsfactory technique for performing this measurement. The method which appears to be most promising is to activate the oxygen in the beryllium samples through the O/sup 16/(n,p)N/sup 16/ reaction with fast neutrons. The N/ sup 16/ decays with beta emission in a haif life of 7.4 seconds to excited states of O/sup 16/. The excited states of O/sup 16/ decay instantly to the ground state with the emission of 6.13 and 7.10 Mev gamma rays. Fast (14 Mev) neutrons are produced through the T(d,n)He/sup 4/ reaction with a 150-kev Cockcroft-Walton accelerator. A rapid transfer system moves the irradiated sample from the region of the accelerator target to a well-shielded NaI (Tl) gamma spectromactivity. The gamma spectrum from this detector is displayed on a multi-channel analyzer. The number of counts registered in the 6 and 7 Mev region of the spectrum is proportional to the oxygen content of the beryllium sample. This activity is compared with the activity of a standard sample irradiated and counted in the same geometry as the beryllium sample. From these datamore » the mass of the oxygen contained in the beryllium sample was calculated. (auth)« less