Measurement of the double polarization observable E in η′-photoproduction

Abstract

The nucleon excitation spectrum is investigated at the Crystal Barrel experiment through different photoproduction reactions. The photoproduction of single η′ mesons off protons is of particular importance since it offers the opportunity to study the high-lying resonances and therefore the part of the nucleon excitation spectrum where many missing resonances are predicted. Preliminary results of the double polarization observable E and the decomposition of the total cross section into its helicity-dependent components σ1/2 and σ3/2 in η′-photoproduction are presented for beam energies from 1450 MeV to 2320 MeV.