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Truncated Moments of Nonsinglet Parton Distributions in the double logarithmic $ln^2x$ approximation

D. Kotlorz·A. Kotlorz
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Abstract

The method of truncated Mellin moments in a solving QCD evolution equations of the nonsinglet structure functions $F_2^{NS}(x,Q^2)$ and $g_1^{NS}(x,Q^2)$ is presented. All calculations are performed within double logarithmic $ln^2x$ approximation. An equation for truncated moments which incorporates $ln^2x$ effects is formulated and solved for the unintegrated structure function $f^{NS}(x,Q^2)$. The contribution to the Bjorken sum rule coming from the region of very small $x$ is quantified. Further possible improvement of this approach is also discussed.

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D. Kotlorz, A. Kotlorz. 2004-03-05. Truncated Moments of Nonsinglet Parton Distributions in the double logarithmic $ln^2x$ approximation. https://arxiv.org/abs/hep-ph/0403061

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