Development Of Shell Closures At N=32,34. Ii. Lowest Yrast Excitations In Even-Even Ti Isotopes From Deep-Inelastic Heavy-Ion Collisions

Gamma rays from neutron-rich nuclei in the vicinity of Z=20, N=28 have been studied at Gammasphere using deep-inelastic reactions induced by a 330-MeV Ca-48 beam on a thick U-238 target. The yrast gamma-ray cascade of Ti-56 was identified for the first time and the location in energy of the 2(+), 4(+), and 6(+) states was determined. The low-spin Ti-56 yrast structure does not support the presence of a subshell closure at N=34 as suggested on the basis of other data on nuclei in the region as well as shell model calculations with a recently proposed interaction.