Nuclear structure in 95,97Ru nuclei.

P. Chowdhury, * B.A. Brown, U. Garg, & R. D. McKeown, ~ T. P. Sjoreen, **and D. B. Fossan Department ofPhysics, State University ofNew York, Stony Brook, New York 11794 {Received 1 July 1985) The high-spin leve1 structures of the nuclei 9' 7Ru have been studied via the Mo{ Li,p2n)9'Ru and Nb{ Li,3n) Ru reactions, using y-y coincidence, y-8'{6I), and pulsed-beam-y measurements. Shell-model calculations of energy levels and 8{E2)values for Ru have been performed and compared with the experimentally observed levels and the measured 2' and 2 lifetimes. A collective hJ =2 band has been identified with the 1h ll/q neutron state in Ru, and discussed in the context of the general nature of collectivity in nuclei outside the X=50 closed shell. No AJ =1 band associated with the 1g9/2 neutron-hole intruder state was found in either of the X =51,53 Ru nuclei, as observed previously for the 1g9/2 proton-hole intruder states in the Z =51 Sb and Z =53 I nuclei.