　　　　- RCNP Seminar -

　　　Dr. Sean Freeman (University of Manchester, UK)

　　　■Shifts in High-j Single-Particle States Outside Z=50 and N=82

　　　Abstract：
　　　　The relative spectroscopic factors of low-lying states in Sb isotopes in
　　　 proton transfer were measured recently, confirming that the shifts in energy
　　　 of the lowest 7/2+ and 11/2- states do indeed reflect changes in the energies of
　　　 the　proton g7/2 and h11/2 orbitals. These systematic trends in energy with
　　　 neutron excess have recently been attributed to monopole shifts predominantly
　　　 due to the interaction of protons with neutrons filling the h11/2 orbital.
　　　 The interaction has been　associated with the tensor component of the
　　　 nucleon-nucleon interaction.
　　　　 Outside of the N=82 core, the lowest-lying 13/2+ and 9/2- states show similar
　　　 trends, with an increasing separation with increasing neutron excess.
　　　 Single-neutron　transfer experiments indicate that the single-particle strengths
　　　 are more fragmented　than for protons outside Z=50. However, the centroids of
　　　 the i13/2 and h9/2 states　follow a trend in excitation energy, which is consistent
　　　 with shifts induced by the tensor interaction with protons filling mainly the g7/2 orbit.