Polarization measurements in π0 photoproduction from the proton

In the resonance. region, up to W similar to 2 GeV or so, pi(0) photoproduction probes resonance photoproduction, as well as non-resonant production processes. Above the resonance region, data are sparse, and it is not clear whether the reaction will be easier to understand with quark or with meson-baryon degrees of freedom. We have measured the proton recoil polarization for ten incident beam energies, across and above the resonance region. Despite the greatly extended kinematic range of the data, no approach to any existing quark-model prediction is seen.