l - ex / 0 20 70 16 v 2 9 A ug 2 00 2 Concentration of electric dipole strength below the neutron separation energy in N = 82 nuclei
نویسندگان
چکیده
The semi-magic nuclei 138 Ba, 140 Ce, and 144 Sm 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.
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X iv : n uc l - ex / 0 20 70 16 v 1 2 5 Ju l 2 00 2 Concentration of electric dipole strength below the neutron separation energy in N = 82 nuclei
The semi-magic nuclei 138 Ba, 140 Ce, and 144 Sm 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.
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