ONSET OF COLLECTIVITY IN THE ODD-ODD NUCLEUS AS-72

High-spin states in the odd-odd nucleus As-72 were investigated by means of coincidence measurements via the (Co(F,alphapn))-Co-59-F-19 and the (Cu(C,alphan))-Cu-65-C-12 reactions at beam energies of 55 MeV and 50 MeV, respectively. Two new rotational-like level sequences of probably opposite parities have been found to feed into the known 7(-) isomer at 562.8 keV. Lifetime measurements for some states of the positive-parity sequence using the Doppler shift attenuation method revealed transition strengths of B(E2) almost-equal-to 40 Weisskopf units. Thus, this band is interpreted as a collective structure built on the two-quasiparticle intruder configuration (pig9/2 x nug9/2).