Radiative Neutron-Capture in Some Low Lying Resonances of ⁵²Cr

Abstract

Resonant radiative neutron-capture in the fast reactor structural materials such as Fe, Ni and Cr is of considerable technological importance. Nuclei in this mass region are also known to exhibit non-statistical single-particle capture effects. These are recognised through, 1) anomalously large partial radiation widths compared with the predictions of the statistical model, 2) significant correlations between the reduced γ-ray widths and the reduced (d,p) stripping widths (spectroscopic factors) leading to the same final state, and 3) significant correlations between reduced neutron widths and partial radiative widths. Explanation of these correlations and numerical calculations of the radiative widths have generally been made within the framework of the channel capture formalism of Lane and Lynn, and Lynn’s valence model specialisation of this formalism.

In this work the absolute primary γ-ray spectra from some low-lying neutron resonances in ⁵²Cr have been measured using the Harwell electron linear accelerator HELIOS as a pulsed neutron source. A comparison of the absolute partial widths with. the predictions of the valence model has been made.