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arXiv · 2408.16552

AAK24: Global QCD analysis on polarized parton distribution in the presence of $A_2$ asymmetry measurements

Fatemeh Arbabifar·Shahin Atashbar Tehrani·Hamzeh Khanpour
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Abstract

This article introduces {\tt AAK24}, a Next-to-Leading Order (NLO) QCD analysis of polarized data from both polarized Deep Inelastic Scattering (DIS) and Semi-Inclusive Deep Inelastic Scattering (SIDIS) experiments on the nucleon. The {\tt AAK24} QCD analysis incorporates SU(2) and SU(3) symmetry breaking, specifically $\delta \bar{u} \neq \delta \bar{d} \neq \delta \bar{s}$, while assuming $\delta \bar{s}$ and $\delta s$ are equal. Emphasizing the significance of the semi-inclusive data, the study explores the determination of polarized sea quark distributions. Recent experimental data from {\tt JLAB17}, {\tt COMPASS16}, and {\tt COMPASS17}, including the $A_2$ asymmetry measurements along with SIDIS observables, are thoroughly examined for their impact on the central values of polarized PDFs, their uncertainties, and overall fit quality. Additionally, we include the nonperturbative target mass corrections (TMC) as well as higher-twist terms (HT) which are particularly important. In this work, the uncertainties are quantified using the standard Hessian method. The main results and findings of the {\tt AAK24} QCD analysis show overall good agreement with the analyzed experimental data, aligning well with other polarized PDF determinations, particularly {\tt DSSV14}, {\tt LSS10}, {\tt JAM17}, and {\tt AKS14}, all considering SU(2) and SU(3) symmetry breaking.

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Fatemeh Arbabifar, Shahin Atashbar Tehrani, Hamzeh Khanpour. 2024-08-29. AAK24: Global QCD analysis on polarized parton distribution in the presence of $A_2$ asymmetry measurements. https://doi.org/10.1140/epjp/s13360-024-05601-5

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