Photoproduction of the Σ+ hyperon using linearly polarized photons with CLAS

Background: Measurements of the polarization observables ς,P,T,Ox,Oz for the reaction γ - p→KS0ς+ using a linearly polarized photon beam of energy 1.1 to 2.1 GeV are reported. Purpose: The measured data provide information on a channel that has not been studied extensively, but is required for a full coupled-channel analysis in the nucleon resonance region. Method: Observables have been simultaneously extracted using likelihood sampling with a Markov-Chain Monte Carlo process. Results: Angular distributions in bins of photon energy Eγ are produced for each polarization observable. T,Ox, and Oz are first time measurements of these observables in this reaction. The extraction of ς extends the energy range beyond a previous measurement. The measurement of P, the recoil polarization, is consistent with previous measurements. Conclusions: The measured data are shown to be significant enough to affect the estimation of the nucleon resonance parameters when fitted within a coupled-channels model.