Giant M1 resonance in 140Ce.

Highly polarized tagged photons were used to measure the distribution of M1 transition strength in /sup 140/Ce at excitations between 6.7 and 8.7 MeV. A strength of summationgGAMMA/sub 0//sup 2/(M1)/GAMMA = 11.2/sub -3.1/ /sup +4.5/ eV corresponding to a B(M1up-arrow) of about 7.5..mu../sub 0//sup 2/ was observed centered at an excitation of 7.95 MeV. This distribution of M1 strength can account for the giant magnetic dipole resonance predicted in /sup 140/Ce.

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