Isospin of the fine structure between 8 and 12 MeV inPb208and its implication for the multipole assignment of the 8.9-MeV resonance

The giant-resonance region between 8 and 12 MeV measured by ($e,e^{\prime }$) in ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ is disentangled into narrow lines (${\Gamma }_{\mathrm{nat}}<400\mathrm{}$ keV) and broad resonances (${\Gamma }_{\mathrm{nat}}>1800\mathrm{}$ keV). The narrow lines at 10.07, 10.60, and 11.37 MeV have an $E2\mathrm{}$ angular distribution, and assumption of $\Delta T=1\mathrm{}$ for them explains controversial experimental results of electromagnetic and hadronic experiments. The new analysis makes an assignment for the 8.9-MeV resonance other than monopole difficult to understand.