The 5.5 MeV Anomalous Gamma Radiation in 205Tl(n,γ)206 Tl

An enhancement at 5.5 MeV in the γ-ray spectra following ther-mal and fast neutron capture in the mass region 180level structure of 206Tl is well known (fig. 1). These states have been observed in the (d, α), (t, α) and (d, p) reactions3–5), The level scheme calculated by Kuo and Herling6) is generally in good agreement with experiment and consequently we have a knowledge of the various proton-hole, neutron-hole amplitudes of many of these states. Such data are invaluable for analysis of the capture γ-ray spectra.