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Nuclear parton distribution functions and their uncertainties

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

We analyze experimental data of nuclear structure-function ratios F_2^A/F_2^{A'} and Drell-Yan cross section ratios for obtaining optimum parton distribution functions (PDFs) in nuclei. Then, uncertainties of the nuclear PDFs are estimated by the Hessian method. Valence-quark distributions are determined by the F_2 data at large x; however, the small-x part is not obvious from the data. On the other hand, the antiquark distributions are determined well at x~0.01 from the F_2 data and at x~0.1 by the Drell-Yan data; however, the large-x behavior is not clear. Gluon distributions cannot be fixed by the present data and they have large uncertainties in the whole x region. Parametrization results are shown in comparison with the data. We provide a useful code for calculating nuclear PDFs at given x and Q^2.

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M. Hirai, S. Kumano, T. -H. Nagai. 2004-07-15. Nuclear parton distribution functions and their uncertainties. https://doi.org/10.1103/physrevc.70.044905

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