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Near threshold Lambda and Sigma production in pp collisions

A. M. Gasparian·J. Haidenbauer·C. Hanhart·L. Kondratyuk·J. Speth
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Abstract

A model calculation for the reactions $pp\to pΛK^+$ and $pp\to NΣK$ near their thresholds is presented. It is argued that the experimentally observed strong suppression of $Σ^0$ production compared to $Λ$ production at the same excess energy could be due to a destructive interference between the $π$ and $K$ exchange contributions in the reaction $pp\to pΣ^0 K^+$. Predictions for $pp\to pΣ^+ K^0$ and $pp\to nΣ^+ K^+$ are given.

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A. M. Gasparian, J. Haidenbauer, C. Hanhart, L. Kondratyuk, J. Speth. 2000-06-30. Near threshold Lambda and Sigma production in pp collisions. https://doi.org/10.1016/s0375-9474(01)00407-9

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