Transition strengths and the role of the f7/2 orbital in 71As

High-spin states in As-71 were studied using the Fe-54(Na-23, alpha 2p) reaction at 80 MeV. Prompt gamma-gamma coincidences were measured using the Florida State University Compton-suppressed Ge array consisting of three clover detectors and seven single-crystal detectors. The existing high-spin level scheme has been verified, and 21 new transitions have been added based on an investigation of weak gamma-ray coincidence relations and relative gamma-ray intensities. Lifetimes of 16 excited states were measured using the Doppler-shift attenuation method applied to the experimental line shapes of decays in all of the known rotational bands. The B(E2) strengths inferred from the lifetimes indicate that moderate to high collective behavior persists to the highest observed spins in the lowest positive-and negative-parity bands, in qualitative agreement with projected shell-model calculations. The band suggested to be based on the pi f(7/2) orbital shows a similar degree of collectivity within the same spin range, with B(E2) values in good agreement with those predicted by the projected shell model assuming a constant prolate deformation of epsilon(2) = +0.27. The experimental Q(t) values in this band are somewhat smaller than predicted by cranked Woods-Saxon calculations.