Measurement of the single polarization observables I[sup c] and I[sup s] in π[sup 0]η photoproduction

Meson photoproduction off the nucleon is a key tool in order to understand the structure of baryons and their excitation spectrum. Especially in the regime of high-lying resonances the photoproduction of multi-meson final states is of increasing importance, given that the cross sections for such processes exceed those for single-meson production. Additionally it gives a handle on sequential decays of such resonances via e.g. the {Delta}(1232) or the S{sub 11}(1535) in the intermediate state. For a complete understanding of the processes involved, the measurement not only of unpolarized cross sections but also of polarization observables is mandatory. With the Crystal Barrel/TAPS experiment, located at the ELSA accelerator facility in Bonn, it was possible to determine such observables using a linearly polarized photon beam impinging on a liquid hydrogen target. The beam asymmetries I{sup c} and I{sup s} are presented for the reaction gp {gamma}{sup {yields}p{yields}}p{pi}{sup 0{eta}}. The latter is a feature exclusive to the acoplanar kinematics of multi-meson final states and has been measured for the first time.