Reactions of Iron-54 with Alpha-Particles

Excitation functions for the (α, p ), (α, n ), (α, p n ), (α, 2 n ), (α, p 2 n +α, 3 n ), (α, α n ), (α, α p n ) and (α, α2 n ) reactions on Fe 54 were measured by the activation method using a “stacked-foil” technique, the alpha-particle energies ranging from 10 MeV to 40 MeV. The predominance of proton emission over neutron emission has been observed. The ratios of σ(α, p )/σ(α, n ) and σ(α, p n )/σ(α, 2 n ) in the region of maximum yield were found to be 3.4 and 60, respectively. The ratio of σ(α, α p n )/σ(α, α2 n ) at 40 MeV was about 180. A small “knee” was observed at the incident alpha-particle energy of about 20 MeV in the excitation function for the (α, 2 n ) reaction. The total reaction cross section was found to agree with the value calculated from continuum theory for a nuclear radius constant r 0 of 1.7×10 -13 cm assuming a nuclear square well potential.