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arXiv · 0711.2557

Global NLO Analysis of Nuclear Parton Distribution Functions

M. Hirai·S. Kumano·T. -H. Nagai
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Abstract

Nuclear parton distribution functions (NPDFs) are determined by a global analysis of experimental measurements on structure-function ratios F_2^A/F_2^{A'} and Drell-Yan cross section ratios σ_{DY}^A/σ_{DY}^{A'}, and their uncertainties are estimated by the Hessian method. The NPDFs are obtained in both leading order (LO) and next-to-leading order (NLO) of α_s. As a result, valence-quark distributions are relatively well determined, whereas antiquark distributions at x>0.2 and gluon distributions in the whole x region have large uncertainties. The NLO uncertainties are slightly smaller than the LO ones; however, such a NLO improvement is not as significant as the nucleonic case.

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M. Hirai, S. Kumano, T. -H. Nagai. 2007-11-16. Global NLO Analysis of Nuclear Parton Distribution Functions. https://doi.org/10.1063/1.2898955

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