SPECTROSCOPY OF RU-95 AT HIGH SPINS

High spin states in the N = 51 nucleus Ru-95 were populated and studied using the reaction Zn-64(Cl-35,3pn)Ru-95 at a beam energy of 140 MeV. Gamma-ray intensities and gamma-gamma coincidences were measured. Multipolarities of the transitions were extracted assuming stretched transitions. Forty new transitions have been found. The positive and negative parity bands have been extended up to spins of 43/2(+) and 39/2(-), respectively. The level scheme can be well understood up to moderate spins in terms of spherical shell model calculations within a limited configuration space. A weak coupling scheme in which a 2d(5/2) neutron is coupled to the excited Ru-94 core was found to work reasonably well and reproduced the main features of the observed Ru-95 yrast spectrum. A more rigorous approach to understanding the structure of these high spin states is the breaking of the N = 50 neutron core. The top three transitions in the positive parity band (492, 599, and 744 keV) appear to be an indication of collective behavior.