Spin‐flip M1 strengths in 208Pb

Spin‐flip M1 strength in 208Pb has been measured in photon scattering experiments with a quasi‐monochromatic, linearly polarized photon beam. The data resolve an M1 giant resonance into at least seven, possibly eight, discrete transitions at energies between 7.1 and 7.4 MeV below the neutron separation energy. The measured M1 strength in this region is found to be larger than the previous report. By comparing the data with a self‐consistent RPA estimation using a semi‐realistic interaction, a role of the tensor force is reconfirmed.