title: Measurement of the transverse target and beam-target asymmetries in η meson photoproduction at MAMI.
abstract: We present new data for the transverse target asymmetry T and the very first data for the beam-target asymmetry F in the γ[over →]p[over →]→ηp reaction up to a center-of-mass energy of W=1.9  GeV. The data were obtained with the Crystal-Ball/TAPS detector setup at the Glasgow tagged photon facility of the Mainz Microtron MAMI. All existing model predictions fail to reproduce the new data indicating a significant impact on our understanding of the underlying dynamics of η meson photoproduction. The peculiar nodal structure observed in existing T data close to threshold is not confirmed.
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authors.affiliation: Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany.
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