Drell-Yan Non-Singlet Spin Cross Sections and Spin Asymmetry to $O(α_s^2)$ (II)

Sanghyeon Chang; Claudio Coriano; R. D. Field

doi:10.1016/s0550-3213(98)00324-1

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arXiv · hep-ph/9803280

Drell-Yan Non-Singlet Spin Cross Sections and Spin Asymmetry to $O(α_s^2)$ (II)

Sanghyeon Chang·Claudio Coriano·R. D. Field

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Abstract

We present predictions for the non-singlet Drell-Yan longitudinal spin cross sections and spin asymmetry, $A_{LL}$, in proton-proton collisions at large $p_T$ at the RHIC energy of $200\gev$ at next-to-leading order QCD. The higher order corrections to the non-singlet polarized cross section, $σ_{NS}^{LL}$, are sizeable and similar to those found for the unpolarized cross section. The non-singlet asymmetry parameter, $A^{NS}_{LL}$, is very stable against higher order corrections and is a direct measurement of the non-singlet (i.e. valence) polarized quark distributions within the proton.

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Sanghyeon Chang, Claudio Coriano, R. D. Field. 1998-03-09. Drell-Yan Non-Singlet Spin Cross Sections and Spin Asymmetry to $O(α_s^2)$ (II). https://doi.org/10.1016/s0550-3213(98)00324-1

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