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Experimental results on the $Sigma^+(1189)$ hyperon transverse polarization in photoproduction on a hydrogen target using the CLAS detector at Jefferson laboratory are presented. The $Sigma^+(1189)$ was reconstructed in the exclusive reaction $gamma+prightarrow K^{0}_{S} + Sigma^+(1189)$ via the $Sigma^{+} to p pi^{0}$ decay mode. The $K^{0}_S$ was reconstructed in the invariant mass of two oppositely charged pions with the $pi^0$ identified in the missing mass of the detected $ppi^+pi^-$ final state. Experimental data were collected in the photon energy range $E_{gamma}$ = 1.0-3.5 GeV ($sqrt{s}$ range 1.66-2.73 GeV). We observe a large negative polarization of up to 95%. As the mechanism of transverse polarization of hyperons produced in unpolarized photoproduction experiments is still not well understood, these results will help to distinguish between different theoretical models on hyperon production and provide valuable information for the searches of missing baryon resonances.
We present new data for the transverse target asymmetry T and the very first data for the beam-target asymmetry F in the $vec gamma vec ptoeta p$ reaction up to a center-of-mass energy of W=1.9 GeV. The data were obtained with the Crystal-Ball/TAPS d
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 F
We report the first measurements of the $E$ beam-target helicity asymmetry for the $vec{gamma} vec{n} to K^{0}Lambda$, and $K^{0}Sigma^{0}$ channels in the energy range 1.70$leq Wleq$2.34 GeV. The CLAS system at Jefferson Lab uses a circularly polari
The transverse polarization of $Lambda$ hyperons was measured in inclusive quasireal photoproduction for various target nuclei ranging from hydrogen to xenon. The data were obtained by the HERMES experiment at HERA using the 27.6 GeV lepton beam and
Despite decades of studies of the photoproduction of hyperons, both their production mechanisms and their spectra of excited states are still largely unknown. While the parity-violating weak decay of hyperons offers a means of measuring their polariz