MEASUREMENT OF THE CROSS SECTION ASYMMETRY Σ FOR γp → π°p OVER THE RANGE Eγ= 0.5 - 1.1

The cross section asymmetry Σ has been measured for the photoproduction of π°-mesons off protons, using the polarized photon beam of the Yerevan 4.5 GeV synchrotron, over the second and third resonance regions. We compare with existing experimental data and recent phenomenological analyses. The influence of these measurements on such analyses is also considered.