Polarization of the Recoil Proton from the Neutral Photoproduction at 800 and 910 Mev

The measurements on the polarization of the recoil protons from the process γ+p→π⁰+p have been extended to higher γ-ray energies, at 90^∘{} in the center-of-mass system. We have found at 910 Mev a polarization, P=-0.45±0.07; at 800 Mev, P=-0.42±0.10. The rather high values of P agree with the hypothesis that the neutral photoproduction in the 500-1000 Mev range can be described by the well-known three resonant states, and strongly indicate that the second and third resonance have opposite parity. The probable quantum numbers are: T=1/2, J=3/2, D pion wave for the second resonance; T=1/2, J=5/2, F wave for the third resonance.