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Photon beam asymmetry $Sigma$ measurements for $omega$ photoproduction in the reaction $vec{gamma} p to omega p$ are reported for photon energies from 1.152 to 1.876 GeV. Data were taken using a linearly-polarized tagged photon beam, a cryogenic hydrogen target, and the CLAS spectrometer in Hall B at Jefferson Lab. The measurements obtained markedly increase the size of the database for this observable, extend coverage to higher energies, and resolve discrepancies in previously published data. Comparisons of these new results with predictions from a chiral-quark-based model and from a dynamical coupled-channels model indicate the importance of interferences between $t$-channel meson exchange and $s$- and $u$-channel contributions, underscoring sensitivity to the nucleon resonances included in those descriptions. Comparisons with the Bonn-Gatchina partial-wave analysis indicate the $Sigma$ data reported here help to fix the magnitudes of the interference terms between the leading amplitudes in that calculation (Pomeron exchange and the resonant portion of the $J^P=3/2^+$ partial wave), as well as the resonant portions of the smaller partial waves with $J^P$= $1/2^-$, $3/2^-$, and $5/2^+$.
Differential cross sections for the reaction $gamma p to K^{*0} Sigma^+$ are presented at nine bins in photon energy in the range from 1.7 to 3.0 GeV. The kstar was detected by its decay products, $K^+pi^-$, in the CLAS detector at Jefferson Lab. The
We report measurements of the photon beam asymmetry $Sigma$ for the reaction $vec{gamma} pto K^+Sigma^0$(1193) using the GlueX spectrometer in Hall D at Jefferson Lab. Data were collected using a linearly polarized photon beam in the energy range of
First results from the longitudinally polarized frozen-spin target (FROST) program are reported. The double-polarization observable E, for the reaction $vec gamma vec p to pi^+n$, has been measured using a circularly polarized tagged-photon beam, wit
We report the first beam-target double-polarization asymmetries in the $gamma + n(p) rightarrow pi^- + p(p)$ reaction spanning the nucleon resonance region from invariant mass $W$= $1500$ to $2300$ MeV. Circularly polarized photons and longitudinally
The reactions $gamma p rightarrow K^{+}Sigma^{pm}pi^{mp}$ were studied with the SAPHIR detector using a tagged photon beam at the electron stretcher facility ELSA in Bonn. The decays $Sigma^{-} rightarrow npi^{-}$ and $Sigma^{+} rightarrow npi^{+}, p