Properties of nuclear levels photoexcited by neutron-capture γ-rays of Ti and Cu

Neutron capture γ-rays of Ti and Cu have been used to photoexcite nuclear levels in the 5-8 MeV region in various nuclei. The spins, parities, and radiative widths of resonance levels in ⁶⁵Cu, ¹⁰⁰Mo, ¹¹⁸Sn, ¹²⁶Te, ¹³⁰Te, ¹⁸⁶W and ²⁰⁹Bi, were measured. The spins of the resonance levels were obtained by angular distribution measurements, and the parities by polarization measurements. The radiative widths were determined using nuclear self-absorption, temperature variation and absolute scattering cross section measurements. The total radiative widths were found to be of the same magnitude as those of neutron resonances, after applying a correction allowing for different excitation energies. Some E2 M1 mixing ratios of high energy transitions were obtained; the E2 widths were found to be of the same magnitude as those obtained in (n, γ) experiments.