We present results on vector meson photoproduction via +yp -. Vp in the LBL-SLAC 82" hydrogen bubble chamber exposed to a linearly polarized photon beam at 2.8, 4.7 and 9.3 GeV. We find p" production to have the characteristics of a diffractive process, i.e., a cross section decreasing slowly with energy and a differential cross section with slope of -6.5 GeV -2 . Within errors the p" production amplitudes are entirely due to natural parity exchange. S-channel helicity is conserved to a high degree in the y --+p' transition. We find evidence for small helicity flip amplitudes for 7rr pairs in the ,o" region. Photoproduction of w mesons is separated into its natural (aN) and unnatural (vu) parity exchange contributions. The E -Y and t-dependence and the spin density matrix of the unnatural parity exchange contribution are consistent with an OPE process.The natural parity exchange part has characteristics similar to p" production.At 9.3 GeV the ratio of a@') to aN(w) is -7. The slope of the Q? differential cross section is -4.5 GeVm2, smaller than that of p" and w production. Natural parity exchange is the main contributor to + production. No evidence for higher mass vector mesons is found in 717~~ ~TTT or m final states. The s-and tdependence of Compton scattering as calculated from p, w and 9 photoproduction using VDM agree with experiment, but the predicted Compton cross section is too small by a factor of two.

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ARTICLESNeutral strange particle production in neutrino and antineutrino charged-current interactions on neon D. D e P r o~p o ,~~' M. Kalelkar,16 M. ~d e r h o l z , '~ H. ~k b a r i , l ' t P.P. ~l l p o r t ,~~