Effect of the pigmy resonance on the calculations of the neutron capture cross section

Abstract

A comparison of the experimental cross sections of the (n, γ) reaction for several nuclei (103Rh, 127I, 181Ta, 197Au) with the compound nucleus model calculations has been made. In the formula used for the probability of gamma-ray emission from the compound nucleus, the presence of the well-known giant resonance was accounted for, as well as the presence of the "pigmy resonance" appearing at the energy Eγ ≈ 6 MeV. The agreement with the experimental values is better in this case than when the "pigmy resonance" is neglected. The same conclusions can be obtained from the calculations of the shape of the spectrum of neutron capture and from the Γγ/D ratio.