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The photoproduction of $omega$ mesons off the proton has been studied in the reaction $gamma pto p,omega$ using the CEBAF Large Acceptance Spectrometer (CLAS) and the frozen-spin target (FROST) in Hall B at the Thomas Jefferson National Accelerator Facility. For the first time, the target asymmetry, $T$, has been measured in photoproduction from the decay $omegatopi^+pi^-pi^0$, using a transversely-polarized target with energies ranging from just above the reaction threshold up to 2.8 GeV. Significant non-zero values are observed for these asymmetries, reaching about 30-40% in the third-resonance region. New measurements for the photon-beam asymmetry, $Sigma$, are also presented, which agree well with previous CLAS results and extend the world database up to 2.1 GeV. These data and additional $omega$-photoproduction observables from CLAS were included in a partial-wave analysis within the Bonn-Gatchina framework. Significant contributions from $s$-channel resonance production were found in addition to $t$-channel exchange processes.
Photoproduction cross sections are reported for the reaction $gamma pto peta$ using energy-tagged photons and the CLAS spectrometer at Jefferson Laboratory. The $eta$ mesons are detected in their dominant charged decay mode, $etato pi^+pi^-pi^0$, and
The differential cross sections and unpolarized spin-density matrix elements for the reaction $gamma pto pomega$ were measured using the CBELSA/TAPS experiment for initial photon energies ranging from the reaction threshold to 2.5 GeV. These observab
The $Sigma$ beam asymmetry in $eta^{prime}$ photoproduction off the proton was measured at the GrAAL polarised photon beam with incoming photon energies of 1.461 and 1.480 GeV. For both energies the asymmetry as a function of the meson production ang
We report on new measurements of the beam asymmetry for omega photo-production on proton and neutron in Hydrogen and Deuterium targets from the GRAAL collaboration. The beam asymmetry values are extracted from the reaction threshold (E_{gamma} = 1.1
Photoproduction of neutral pions has been studied with the CBELSA/TAPS detector for photon energies between 0.92 and 1.68~GeV at the electron accelerator ELSA. The beam asymmetry~$Sigma$ has been extracted for $115^circ < theta_{rm c.m.} < 155^circ$