Excitation of Gamma-Rays by Fast Neutrons of Different Energy, II

Abstract

Atomic cross sections σγ's of Mg, Co and Bi for gamma-ray excitation by fast neutrons of different energies from 2.25 to 2.90MeV were determined. In all three cases anormalics were observed in the cross section energy curves. In the case of Mg, the anormaly observed by MACPHAIL in the total cross section σ_t can be explained almost entirely by that in σγ observed in the present experiment. As Co consists of nearly, and Bi of perfectly single isotope, the results are suited for comparison with theoretical calculations