Mean lives and limits of lifetimes have been determined for some ten mostly yrast states in 7~ by means of the recoil distance Doppler shift technique. The states were excited in the reaction 4~ c~2p) at 115 MeV resp. the reaction 58Ni(14N, pn) at 39 MeV beam energy. The systematic decrease of B(E2) values along the the ground band transitions indicates a band crossing consistent with the ))-ray energies. Effects of continuum feeding times in both reactions are being discussed. The lifetimes of the lowest three yrast transitions in 72Se have been remeasured by means of the reactions 4OCa (36Ar ' 4p) and 6~ (14N, pn).

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High spin states in Br were investigated in the reactions Ni (' O,p2n) and Zn (' C,p2n). By means of yy-and y-neutron multiplicity coincidence measurements, rotational bands of both parities were extended up to 7 MeV excitation energy and spin I = 2 . The lifetimes of 17 yrast states were determined with the recoil distance and Doppler shift attenuation methods; the spin dependence of the side feeding time was also measured. The data have been analyzed in terms of the Strutinsky-Bogolyubov cranking model with a Woods-Saxon average potential. The first crossing observed in the negative parity bands is attributed to the alignment of a g9/2 proton pair; the next irregularity which is also observed in the positive parity band is interpreted as the alignment of g9/2 neutrons. The coexistence of prolate and oblate configurations at low spin and the change of nonaxial deformation with rotational frequency due to the polarization of the even-even core by the odd particle are discussed. The signature inversion visible in the negative parity bands as well as the changes in the signature splitting and reduction of 8(E2) values at high spins may be related to a transition from y~0 ' to y~0 ' triaxial shapes.

High spin states in 85y have been excited in the reaction 72Ge(160, p2n) at 48-60 M eV beam energy. From measurements of n7 and 77 coincidences, excitation functions and angular distributions, the high spin spectrum of 8sy has been established up to 5.4 MeV excitation energy and spin I < 29/2. Lifetimes or limits of lifetimes have been determined for 14 levels via the recoil distance and Doppler shift attenuation method. The g9/2 decoupled proton band is found to backbend at U= 17/2 + as also seen in the reduction of the 17/2+~13/2 + and 21/2+-~17/2 + E2 transition strengths. The lowest (3qp) positive parity band has predominantly a V299/2 X 7~g9/2 structure. The observed negative parity yrast states in the spin range 15/2-<1<29/2-are most probably of (g9/2) 2 x(fs/z,px/2) (3qp) nature as suggested by a comparison of the 84Sr and 85y level structures and electromagnetic transition strengths.

High spin states in 85Rb and 85Sr were populated in the reactions 76Ge(12C, p2n) and 76Ge(lZC,3n), respectively. The lifetimes of twelve states were measured via the recoil distance Doppler shift technique. The positive parity bands in both nuclei associated with the g9] 2 orbit exhibit decrasing E2 strengths for increasing spin value marking the onset of multiparticle excitation.Nuclear Reactions: V6Ge(tZC, p2n)85Rb; 76Ge(lZC, 3n)8SSr; E=42-52 MeV; measured E~, I~, recoil distance Doppler shift. 85Rb, 85Kr levels deduced 3. Enriched targets. Shell model and muli-partMe core coupling calculations.