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On the $Λ$ to $Σ^0$ ratio from proton-proton collisions

A. Sibirtsev·K. Tsushima·W. Cassing·A. W. Thomas
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Abstract

We compare the recent COSY data on the total $pp{\to}pΛ{K^+}$ and $pp{\to}pΣ^0{K^+}$ cross sections with the predictions from two boson exchange models that either are based solely on $π$ and $K$ exchange or include $π$, $η$ and $ρ$ exchange as well as the virtual excitation of intermediate baryon resonances. Both models are found to reproduce the data after the inclusion of final state hyperon-nucleon interactions. Thus, within the experimental uncertainties, both models also roughly reproduce the strong dependence of the $Λ$ to $Σ^0$ ratio as a function of the excess energy near threshold, as well as at higher energies.

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A. Sibirtsev, K. Tsushima, W. Cassing, A. W. Thomas. 2000-05-05. On the $Λ$ to $Σ^0$ ratio from proton-proton collisions. https://arxiv.org/abs/nucl-th/0004022

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