Study of the Hyperon-Nucleon Interaction in Exclusive Λ Photoproduction off the Deuteron

Nicholas Zachariou,Tongtong Cao,Yordanka Ilieva,C Elster,D.R Phillips,C.D Roberts

doi:10.1051/epjconf/201611307002

Nicholas Zachariou, Tongtong Cao + Show 4 more

Open Access

https://doi.org/10.1051/epjconf/201611307002

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Abstract

The study of final-state interactions in exclusive hyperon photoproduction off the deuteron is a promising approach to extract information about the hyperon-nucleon (YN) interaction. First preliminary results on the azimuthal asymmetry ∑, as well as the polarization transfer coeffcients Ox, Oz, Cx, and Cz for the reaction γd → K+ Λn initiated with linearly and circularly polarized photon beam are presented. The data were taken with the CLAS detector in Hall B of Jefferson Lab during the E06-103 experiment. The large kinematic coverage of the CLAS, combined with the exceptionally high quality of the experimental data, allows identifying and selecting final-state interaction events to extract single- and double-polarization observables and their kinematical dependencies.

Highlights

Understanding of the nucleon-nucleon (NN) and hyperon-nucleon (Y N) interaction is necessary in order to obtain a comprehensive picture of the strong interaction
The study of the Y N interaction is important for understanding hadron dynamics involving strange quarks, and enables the extension of the baryon-baryon interaction to a more unified picture demanded by SU(3) symmetry
A new theoretical approach allows the extraction of the spin-averaged Λ − n scattering lengths by studying the Λ − n invariant mass distributions of observables [5]. This approach has been tested on inclusive K+ hadron-production data and on pseudodata on deuteron photoproduction indicating that the current poorly-determined scattering lengths can be further constrained from final state interactions (FSI)

Summary

Introduction

Understanding of the nucleon-nucleon (NN) and hyperon-nucleon (Y N) interaction is necessary in order to obtain a comprehensive picture of the strong interaction. The best approach to constrain these is to use Y N elastic scattering, but the challenges imposed by hyperon beams and targets result in data of poor quality and energy limitations. The simplicity of the target, as well as the fact that the electromagnetic interaction is well understood, allows us to select kinematics where FSI between the hyperon and the spectator nucleon are greatly enhanced.

Results

Conclusion