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Lambda Polarization in Polarized Proton-Proton Collisions at RHIC

C. Boros·J. T. Londergan·A. W. Thomas
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Abstract

We discuss Lambda polarization in semi-inclusive proton-proton collisions, with one of the protons longitudinally polarized. The hyperfine interaction responsible for the $Δ$-$N$ and $Σ$-$Λ$ mass splittings gives rise to flavor asymmetric fragmentation functions and to sizable polarized non-strange fragmentation functions. We predict large positive Lambda polarization in polarized proton-proton collisions at large rapidities of the produced Lambda, while other models, based on SU(3) flavor symmetric fragmentation functions, predict zero or negative Lambda polarization. The effect of $Σ^0$ and $Σ^*$ decays is also discussed. Forthcoming experiments at RHIC will be able to differentiate between these predictions.

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C. Boros, J. T. Londergan, A. W. Thomas. 2000-02-08. Lambda Polarization in Polarized Proton-Proton Collisions at RHIC. https://doi.org/10.1103/physrevd.62.014021

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