Photoneutron Polarization Studies of the GiantM1Resonance inPb208

The photoneutron polarization from states near threshold was measured, for the first time, for the reaction ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}(\gamma , n_0){}_{}{}^{207}{}_{}{}^{}\mathrm{Pb}$ throughout the neutron energy range 500 to 1000 keV. Spin and parity assignments were made for these states. The giant $M1\mathrm{}$ resonance in ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ was found to be less fragmented than previously thought. The data suggest that there is some "missing" $M1\mathrm{}$ strength in ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$.