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arXiv · hep-ph/9806276

Spin asymmetries at RHIC and polarized parton distributions

S. Hino·M. Hirai·S. Kumano·M. Miyama
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Abstract

We discuss polarized parton distributions and their effects on spin asymmetries at RHIC. In particular, transversity distributions and transverse spin asymmetry are studied. First, we show the $Q^2$ evolution difference between a transversity distribution and a corresponding longitudinally polarized distribution. The difference could be an important test of perturbative QCD in high-energy spin physics. Then, the transverse spin asymmetry $A_{TT}$ is calculated with possible transversity distributions. Next, we study antiquark flavor asymmetry $Δ_{_T} \bar u/ Δ_{_T} \bar d$ in the transversity distributions by using a simple model. Its effects on the transverse spin asymmetry are also discussed.

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S. Hino, M. Hirai, S. Kumano, M. Miyama. 1998-06-05. Spin asymmetries at RHIC and polarized parton distributions. https://arxiv.org/abs/hep-ph/9806276

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