Large scale shell model calculations for even-even ${}^{62-66}$Fe isotopes

Abstract

The recently measured experimental data of Legnaro National Laboratories on neutron rich even isotopes of ${}^{62-66}$Fe with A=62,64,66 have been interpreted in the framework of large scale shell model. Calculations have been performed with a newly derived effective interaction GXPF1A in full $fp$ space without truncation. The experimental data is very well explained for ${}^{62}$Fe, satisfactorily reproduced for ${}^{64}$Fe and poorly fitted for ${}^{66}$Fe. The increasing collectivity reflected in experimental data when approaching N=40 is not reproduced in calculated values. This indicates that whereas the considered valence space is adequate for ${}^{62}$Fe, inclusion of higher orbits from $sdg$ shell is required for describing ${}^{66}$Fe.

10 pages, 6 figures