A systematic study of activation analysis with cyclotron-produced neutrons for (n, 2n), (n, p) and (n, α) reactions is presented.
The limits of detection for elements of atomic number from 6 to 80 are given. The possibilities of optimization of irradiation
conditions by the choice of the most suitable neutron spectrum are discussed. The potential of this fast neutron activation
analysis method is compared with that of 14 MeV neutron activation analysis.
Authors:H. Münzel, F. Michel, P. Coetzee, and V. Krivan
The possible application of cyclotron-produced fast neutrons to activation analysis for oxygen based on the16O(n, p)16N reaction has been investigated. Neutrons were produced by bombarding a thick beryllium target with 22 to 45 MeV deuterons.
It was found that the sensitivity increases rapidly with the energy of the deuterons. Using 45 MeV deuterons and a 10 μA beam
current a sensitivity of about 20 counts per 1 μg oxigen could be achieved, enabling the determination of less than 1 μg oxigen.
In a direct comparison it was experimentally established that the sensitivity for cyclotron-produced neutrons assuming a deuteron
beam of about 10 μA, is up to two orders of magnitude higher than that achievable for 14 MeV neutrons with a flux of about
1010 n/s. The interference of fluorine is at about the same level for both the cyclotron-produced and 14 MeV neutrons. Using cyclotron-produced
fast neutrons in the investigated energy range, sodium and magnesium can also interfere, but only to a very much lower extent.