SENIORITY UPSILON=5 STATES IN NB-89(41)48

Yrast and yrare states in the nucleus Nb-89 have been studied in the r eaction (Ni(Ar,5p)-Ni-58-Ar-36 by measuring gammagamma coincidences an d directional correlation orientation ratios with the OSIRIS array. In addition, gamma-ray singles angular distributions have been taken wit h the reaction (Ni(Cl,4p)-Ni-58-Cl-35. Up to the highest spins observe d (37/2+, 33/2-), the states identified line up with the ones predicte d by the spherical shell model, taking into account three proton parti cles and two neutron holes in the 99/2 and P1/2 single-particle orbits . The shell model also reproduces most of the measured branching and E 2/M1 mixing ratios. The mean lifetime of the 2152 keV 17/2- yrast stat e was determined as 0.74(7) ns.