Measurement of the γn→K+Σ- at Jefferson Lab

A comprehensive study of the electromagnetic strangeness production has been undertaken at Jefferson Lab. Among the six elementary strangeness photoproduction reactions on the nucleon, γn→K0Λ, γn→K0Σ0, γn→K+Σ-, γp→K+Λ, γp→K+Σ0, and γp→K0Σ+, there are cross section data for all γp reactions. For the γn reactions, there is only data for the γn→K+Σ- channel, and in a very limited energy and angular range. The actual theoretical predictions for the strangeness photoproduction cross section on neutron differ widely depending on the data set fitted for the proton channels. Here will be presented preliminary γn(p)→K+Σ-(p) differential cross section measured with the CLAS large acceptance spectrometer at the Jefferson Lab Hall-B, over a wide range of kaon scattering angles (10 circle and 140 circle) using a deuterium target with a tagged photon beam in the energy range from 1.0 up to 3.6 GeV. These measurements can be used to improve the predictive power of the actual theoretical description of hyperon photoproduction by adding more constraints to the Kaon-Hyperon-Nucleon coupling constants.