Concentration of electric dipole strength below the neutron separation energy in N = 82 nuclei
arXiv:nucl-ex/0207016 · doi:10.1016/S0370-2693(02)02309-2
Abstract
The semi-magic nuclei Ba-138, Ce-140, and Sm-144 have been investigated in photon scattering experiments up to an excitation energy of about 10 MeV. The distribution of the electric dipole strength shows a resonance like structure at energies between 5.5 and 8 MeV exhausting up to 1% of the isovector E1 Energy Weighted Sum Rule.
10 pages, 3 figures