Beam-Target Helicity Asymmetry $E$ in $K^0\hat{I}›$ and $K^0\hat{I}{\pounds }^0$ Photoproduction on the Neutron

Abstract

We report the first measurements of the $E$ beam-target helicity asymmetry for the ${\vec{\hat{I}}}^3\vec{n}\to K^0\hat{I}›$, and $K^0\hat{I}{\pounds }^0$ channels in the energy range 1.70$\le W\le$2.34 GeV. The CLAS system at Jefferson Lab uses a circularly polarized photon beam and a target consisting of longitudinally polarized solid molecular hydrogen deuteride with low background contamination for the measurements. The multivariate analysis method boosted decision trees was used to isolate the reactions of interest. Comparisons with predictions from the KaonMAID, SAID, and Bonn-Gatchina models are presented. These results will help separate the isospin $I=0$ and $I=1$ photo-coupling transition amplitudes in pseudoscalar meson photoproduction.

14 pages, 9 figures; Revised to match published version