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Scale evolution of nuclear parton distributions

K. J. Eskola·V. J. Kolhinen·P. V. Ruuskanen
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Abstract

Using the NMC and E665 nuclear structure function ratios $F_2^A/F_2^D$ and $F_2^A/F_2^{C}$ from deep inelastic lepton-nucleus collisions, and the E772 Drell--Yan dilepton cross sections from proton-nucleus collisions, and incorporating baryon number and momentum sum rules, we determine nuclear parton distributions at an initial scale $Q_0^2$. With these distributions, we study QCD scale evolution of nuclear parton densities. The emphasis is on small values of $x$, especially on scale dependence of nuclear shadowing. As the main result, we show that a consistent picture can be obtained within the leading twist DGLAP evolution, and in particular, that the calculated $Q^2$ dependence of $F_2^{Sn}/F_2^{C}$ agrees very well with the recent NMC data.

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K. J. Eskola, V. J. Kolhinen, P. V. Ruuskanen. 1998-02-18. Scale evolution of nuclear parton distributions. https://doi.org/10.1016/s0550-3213(98)00589-6

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