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arXiv · 1608.02766

The electromagnetic form factors of the $Λ$ in the timelike region

J. Haidenbauer·U. -G. Meißner
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Abstract

The reaction $e^+e^- \to \bar ΛΛ$ is investigated for energies close to the threshold. Specific emphasis is put on the role played by the interaction in the final $\bar ΛΛ$ system which is taken into account rigorously. For that interaction a variety of $\bar ΛΛ$ potential models is employed that have been constructed for the analysis of the reaction $\bar p p \to \bar ΛΛ$ in the past. The enhancement of the effective form factor for energies close to the $\bar ΛΛ$ threshold, seen in pertinent experiments, is reproduced. Predictions for the $Λ$ electromagnetic form factors $G_M$ and $G_E$ in the timelike region and for spin-dependent observables such as spin-correlation parameters are presented.

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J. Haidenbauer, U. -G. Meißner. 2016-08-09. The electromagnetic form factors of the $Λ$ in the timelike region. https://doi.org/10.1016/j.physletb.2016.08.067

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