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arXiv · hep-ph/9905559

Transversity distributions and Drell-Yan spin asymmetries

M. Miyama
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Abstract

We discuss transversity distributions and Drell-Yan transverse double spin asymmetries. First, the antiquark flavor asymmetry $Δ_{_T} \bar u/Δ_{_T} \bar d$ is discussed by using two different descriptions, a meson-cloud model and a Pauli exclusion model. We find that both calculations produce a significant $Δ_{_T} \bar d$ excess over $Δ_{_T} \bar u$. Next, we study its effects on the transverse spin asymmetry $A_{_{TT}}$ and on the Drell-Yan proton-deuteron asymmetry $Δ_{_T}σ^{pd}/2 Δ_{_T}σ^{pp}$. We find that the ratio $Δ_{_T}σ^{pd}/2 Δ_{_T}σ^{pp}$ is very useful for investigating the flavor asymmetry effect.

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M. Miyama. 1999-05-31. Transversity distributions and Drell-Yan spin asymmetries. https://doi.org/10.1016/s0920-5632(99)00801-4

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