Photoproduction of Rho Mesons from Hydrogen and Carbon by Linearly Polarized Photons

The photoproduction of ${\rho }^0$ mesons from hydrogen and carbon has been measured at 3.5 GeV using polarized photons from coherent bremsstrahlung produced by 10-GeV electrons on a diamond crystal. Asymmetry ratios for carbon and hydrogen are measured and are consistent with the mainly diffractive nature of ${\rho }^0$ photoproduction. A small nondiffractive component is suggested in the case of hydrogen.