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arXiv · 0707.0534

Anti-Hyperon polarization in high energy pp collisions with polarized beams

Ye Chen·Zuo-tang Liang·Ernst Sichtermann·Qing-hua Xu·Shan-shan Zhou
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Abstract

We study the longitudinal polarization of the Sigma_bar and Xi_bar anti-hyperons in polarized high energy pp collisions at large transverse momenta, extending a recent study for the Lambda_bar anti-hyperon. We make predictions by using different parametrizations of the polarized parton densities and models for the polarized fragmentation functions. Similar to the Lambda_bar polarization, the Xi_bar0 and Xi_bar+ polarizations are found to be sensitive to the polarized anti-strange sea in the nucleon. The Sigma_bar- and Sigma_bar+ polarizations show sensitivity to the light sea quark polarizations, Δ\bar u(x) and Δ\bar d(x), and their asymmetry.

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Ye Chen, Zuo-tang Liang, Ernst Sichtermann, Qing-hua Xu, Shan-shan Zhou. 2008-08-31. Anti-Hyperon polarization in high energy pp collisions with polarized beams. https://doi.org/10.1103/physrevd.78.054007

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