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arXiv · hep-ph/9906484

Nuclear Parton Distributions - a DGLAP Analysis

K. J. Eskola·V. J. Kolhinen·P. V. Ruuskanen·C. A. Salgado
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Abstract

Nuclear parton distributions $f_A(x,Q^2)$ are studied within a framework of the DGLAP evolution. Measurements of $F_2^A/F_2^D$ in deep inelastic $lA$ collisions, and Drell--Yan dilepton cross sections measured in $pA$ collisions are used as constraints. Also conservation of momentum and baryon number is required. It is shown that the calculated $Q^2$ evolution of $F_2^{\rm Sn}/F_2^{\rm C}$ agrees very well with the recent NMC data, and that the ratios $R_f^A=f_A/f$ are only moderately sensitive to the choice of a specific modern set of free parton distributions. For general use, we offer a numerical parametrization of $R_f^A(x,Q^2)$ for all parton flavours $f$ in $A>2$, and at $10^{-6}\le x \le 1$ and $2.25 {\rm GeV}^2\le Q^2\le 10^4 {\rm GeV}^2$.

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K. J. Eskola, V. J. Kolhinen, P. V. Ruuskanen, C. A. Salgado. 1999-06-24. Nuclear Parton Distributions - a DGLAP Analysis. https://doi.org/10.1016/s0375-9474(99)85108-2

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