Compound-statistical features of deuteron-induced reactions: (I). Radiative capture of 4–15 MeV deuterons

Abstract

Absolute cross sections and excitation functions for the 30Si(d, γ) 32P and 138Ba(d, γ) 140La reactions from ≈ 4 to 15 MeV have been measured radiochemically using the stacked target technique. The 30Si(d, γ) cross sections above 5 MeV are 110 to 160 μb and exhibit little energy dependence. The 138Ba(d, γ) excitation function peaks at ≈ 22 μb near 10 MeV. The compound nucleus mechanism, formulated from continuum-theory cross sections and statistical-model calculations using Fermi gas level densities, reproduces both the magnitudes and the dissimilar energy dependences of the two excitation functions. Inverse E1 photonuclear cross sections were calculated both for the giant resonance shape used by Carver and Jones and for that proposed by Lane and Lynn, the former providing more satisfactory agreement with experiment, especially in the Si reaction. It is concluded that these radiative deuteron capture reactions can be explained in terms of compound nucleus formation followed by statistical de-excitation.