Global NLO Analysis of Nuclear Parton Distribution Functions
نویسندگان
چکیده
Nuclear parton distribution functions (NPDFs) are determined by a global analysis of experimental measurements on structure-function ratios FA 2 /F A 2 and Drell-Yan cross section ratios σ A DY /σA ′ DY , 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 αs. 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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