Single π± photoproduction from complex nuclei at 2 and 3 GeV

Abstract The reaction γ A → A ∗ π ± was studied for Be, C, Al, Cu, Ag, Pb and CH 2 targets at photon energies E γ max =2.05 and 2.95 GeV and four momentum transfers | t | respectively 0.3 and 0.58 (GeV/ c ) 2 . The values obtained for Z eff are shown to be independent, within the errors, of photon energies from 2 to 16 GeV (SLAC). A comparison was made with a theoretical calculation. The A -dependence of the ratio of π − /π + production for these nuclei and the difference between the radius of proton-neutron distribution in Ag and Pb are given as well.