M1 and E1 resonant scattering of gamma rays from neutron capture in iron

The parities of levels excited by resonance scattering of γ rays from neutron capture in iron were measured with a Compton polarimeter. The spins and parities of resonance levels in four isotopes were thus found to be ²⁰⁸Pb (7.279 MeV, 1⁻), ¹¹²Cd (7.632 MeV, 1⁻), 141Pr(7.632MeV,72−) role=presentation style=font-size: 90%; display: inline-block; position: relative;>${}^{141}\text{Pr}\text{(7.632}\text{MeV}\text{,}\text{7}\text{2}{}^{\mathrm{-}}\text{)}$${}^{141}\text{Pr}\text{(7.632}\text{MeV}\text{,}\text{7}\text{2}{}^{\mathrm{-}}\text{)}$ and ⁶²Ni (7.646 MeV, 1⁻), which correspond to E1, M1, E1 and M1 radiation, respectively. These results disagree with Axel's suggestion that these resonances may be associated with the tail of the electric giant dipole resonance.