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arXiv · hep-ex/0611036

Separated Structure Functions for the Exclusive Electroproduction of $K^+Λ$ and $K^+Σ^0$ Final States

Abstract

We report measurements of the exclusive electroproduction of $K^+Λ$ and $K^+Σ^0$ final states from a proton target using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The separated structure functions $σ_T$, $σ_L$, $σ_{TT}$, and $σ_{LT}$ were extracted from the $Φ$- and $ε$-dependent differential cross sections taken with electron beam energies of 2.567, 4.056, and 4.247 GeV. This analysis represents the first $σ_L/σ_T$ separation with the CLAS detector, and the first measurement of the kaon electroproduction structure functions away from parallel kinematics. The data span a broad range of momentum transfers from $0.5\leq Q^2\leq 2.8$ GeV$^2$ and invariant energy from $1.6\leq W\leq 2.4$ GeV, while spanning nearly the full center-of-mass angular range of the kaon. The separated structure functions reveal clear differences between the production dynamics for the $Λ$ and $Σ^0$ hyperons. These results provide an unprecedented data sample with which to constrain current and future models for the associated production of strangeness, which will allow for a better understanding of the underlying resonant and non-resonant contributions to hyperon production.

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BibTeXRIS

P. Ambrozewicz, D. S. Carman, R. J. Feuerbach, M. D. Mestayer, B. A. Raue, R. A. Schumacher, A. Tkabladze. 2006-11-21. Separated Structure Functions for the Exclusive Electroproduction of $K^+Λ$ and $K^+Σ^0$ Final States. https://doi.org/10.1103/physrevc.75.045203

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