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arXiv · 0801.1502

Heavy-quark contributions to the ratio F_L/F_2 at low x

Alexey Yu. Illarionov·Bernd A. Kniehl·Anatoly V. Kotikov
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Abstract

We study the heavy-quark contribution to the proton structure functions F_2^i(x,Q^2) and F_L^i(x,Q^2), with i=c,b, for small values of Bjorken's x variable at next-to-lading order and provide compact formulas for their ratios R_i=F_L^i/F_2^i that are useful to extract F_2^i(x,Q^2) from measurements of the doubly differential cross section of inclusive deep-inelastic scattering at DESY HERA. Our approach naturally explains why R_i is approximately independent of x and the details of the parton distributions in the small-x regime.

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Alexey Yu. Illarionov, Bernd A. Kniehl, Anatoly V. Kotikov. 2008-01-09. Heavy-quark contributions to the ratio F_L/F_2 at low x. https://doi.org/10.1016/j.physletb.2008.02.068

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