DEFORMED I13 2 BANDS AND PROLATE OBLATE SHAPE COEXISTENCE IN TL-185 AND TL-187/

High spin states in the very neutron-deficient isotopes 185Tl and 187T l have been identified from gamma-gamma coincidence measurements perfo rmed with the reactions (Gd(Cl, 4n))-Gd-154-Cl-35 and (Tb(S, 4n))-Tb-1 59-S-32. Unambiguous mass assignments were obtained using a Fragment M ass Analyzer and the reactions (Gd(Ar, p4n))-Gd-154-Ar-36 and (Gd(Ar, p3n))-Gd-155-Ar-56. Structures are observed corresponding to both an i 13/2 proton coupled to a prolate deformed core, and also h9/2 and i13/ 2 protons coupled to an oblate deformed core. The proposed 13/2+ [606] intrinsic states are isomeric, with meanlives of 12 +/- 2 ns in 185Tl and 1.0 +/- 0.2 ns in 187Tl. Equilibrium deformation calculations for the excitation energies of intrinsic states reproduce general trends, but overestimate the bandhead energies of high-j states.