Large E1 and M1 Radiative Widths in Nuclei near Closed Shells

The radiative widths, spins and parities of ten levels photoexcited by the (γ,γ′) reaction at excitation around 7 MeV in La139, Ce140, Pr141, Nd142, Nd144, Tl205, and Bi209, were measured. The γ beam was produced by thermal-neutron capture in titanium, iron, cobalt, and copper. The spins of the resonance levels were obtained by angular-distribution measurements and the parities were determined by using a Compton polarimeter. These levels together with other resonance levels in N∼82 and N∼126 nuclei are discussed with regard to a possible connection to a giant M1 resonance.