Test ofs-channel helicity conservation in inelasticρ0diffraction in 20-GeV photoproduction

The reaction ..gamma..p..-->..rho/sub fast//sup 0/p..pi../sup +/..pi../sup -/ has been studied with the linearly polarized 20-GeV monochromatic photon beam at the SLAC Hybrid Facility to test the prediction of s-channel helicity conservation in inelastic diffraction for t' ..p..pi../sup +/..pi../sup -/, and the p..pi../sup +/..pi../sup -/ mass distribution compares well and scales according to the vector dominance model with that produced in ..pi../sup + -/p..--> pi../sub fast//sup + -/p..pi../sup +/..pi../sup -/.