Band structures in near spherical 138Ce

The high spin states of N = 80 Ce-138 have been populated in the fusion evaporation reaction Te-130(C-12, 4n)Ce-138 at E-beam = 65 MeV. The gamma transitions belonging to various band structures were detected and characterized using an array of five Clover Germanium detectors. The level scheme has been established up to a maximum spin and excitation energy of 23h and 9511.3 keV, respectively, by including 53 new transitions. The negative parity Delta I = 1 band, developed on the 6536.3 keV 15(-) level, has been conjectured to be a magnetic rotation band following a semiclassical analysis and comparing the systematics of similar bands in the neighboring nuclei. The said band is proposed to have a four quasiparticle configuration of vertical bar pi g(7/2)h(11/2)vertical bar circle times vertical bar nu h(11/2)vertical bar(-2). Other band structures are interpreted in terms of multi-quasiparticle configurations, based on Total Routhian Surface (TRS) calculations. For the low and medium spin states, a shell model calculation using a realistic two body interaction has been performed using the code OXBASH. (C) 2009 Elsevier B.V. All rights reserved.