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arXiv · 1601.07782

Iterative Monte Carlo analysis of spin-dependent parton distributions

Nobuo Sato·W. Melnitchouk·S. E. Kuhn·J. J. Ethier·A. Accardi
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Abstract

We present a comprehensive new global QCD analysis of polarized inclusive deep-inelastic scattering, including the latest high-precision data on longitudinal and transverse polarization asymmetries from Jefferson Lab and elsewhere. The analysis is performed using a new iterative Monte Carlo fitting technique which generates stable fits to polarized parton distribution functions (PDFs) with statistically rigorous uncertainties. Inclusion of the Jefferson Lab data leads to a reduction in the PDF errors for the valence and sea quarks, as well as in the gluon polarization uncertainty at $x \gtrsim 0.1$. The study also provides the first determination of the flavor-separated twist-3 PDFs and the $d_2$ moment of the nucleon within a global PDF analysis.

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Nobuo Sato, W. Melnitchouk, S. E. Kuhn, J. J. Ethier, A. Accardi. 2016-01-28. Iterative Monte Carlo analysis of spin-dependent parton distributions. https://doi.org/10.1103/physrevd.93.074005

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