Structure of neutron-rich A»60 nuclei: A theoretical perspective,Y. Sun^†, Department of Physics, Shanghai Jiao Tong University, Shanghai 200240, China − One of the current nuclear structure studies focuses on the neutron-rich A»60 nuclei. Recent experiments have reached high-spin regions in some neutron-rich Cr, Mn, and Fe isotopes, which contain more useful information for understanding the importance of the neutron g9=2 orbital in nuclei with neutron number near 40.  This talk will give a theoretical perspective. We have applied both projected shell model and large-scale spherical shell model to study low- and high-spin states in these nuclei [1-5]. The former model can use a large model space but requires an assumption of deformed single-particle states to start with. The latter model is more general but can only discuss the physics in a limited model space. We compare results of the two methods, and show that with increasing neutron number, evolution of shell gaps, shape changes, variation in high-spin levels and B(E2)'s, the high-K isomeric states, etc, are related to the neutron g9=2 orbit. We explain how a system with a soft core near the ground state stabilizes the shape with the aid of rotation. With participation of the neutron g9=2 particles, bands with features of magnetic rotation show up in this mass region.

[1] K. Kaneko, Y. Sun, M. Hasegawa, T. Mizusaki, Phys. Rev. C 78 (2008) 064312.

[2] Y. Sun, Y.-C. Yang, H.-L. Liu, K. Kaneko, M. Hasegawa, T. Mizusaki, Phys. Rev. C 80 (2009) 054306.

[3] Y.-C. Yang, Y. Sun, K. Kaneko, M. Hasegawa, Phys. Rev. C 82 (2010) 031304(R).

[4] Y.-C. Yang, H. Jin, Y. Sun, K. Kaneko, Phys. Lett. B 700 (2011) 44.

[5] H. Jin, Y. Sun, K. Kaneko, S. Tazaki, M. Hasegawa, to be published.

^†Work supported by the National Natural Science Foundation of China under contract No.11135005 and 11075103.