CLAS Collaboration - Hall B, Jefferson Laboratory

Strangeness channels are important in the experimental search for missing baryon resonances. Phenomenological reaction models for the extraction of resonance parameters, such as coupled-channels analyses, require data for many observables, in different channels, and on different targets. The analysis presented in this work is the first measurement of the beam asymmetry over a wide range in the kaon azimuthal center-of-mass angle (which is essential for accessing the s-channel contribution) for the exclusive $\gamma n \rightarrow K^+ \Sigma^-$ reaction, using the deuteron as a quasi-free neutron target. The data used were from the CLAS g13b run period (experiment E06-103) at Jefferson Lab, which used linearly polarized tagged real photons with energies between 1.1 and 2.3 GeV. Results are shown for photon energies between 1.7 and 2.3 GeV. They agree well (within uncertainties) with the beam asymmetries obtained at LEPS for forward angles.