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Small -x behavior of the non-singlet and singlet structure functions g_1

B. I. Ermolaev·M. Greco·S. I. Troyan
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Abstract

Explicit expressions for the non-singlet and singlet structure functions g_1 at the small $x$-region are obtained. They include the total resummation of double-logarithmic contributions and accounting for the running QCD coupling effects. We predict that both the non-singlet and singlet g_1 asymptotically ~ x^{- Δ}, with the singlet intercept = 0.86 and being more than twice larger than the non-singlet intercept = 0.4. The impact of the initial quark and gluon densities on the sign of g_1 at x << 1 is discussed.

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B. I. Ermolaev, M. Greco, S. I. Troyan. 2003-12-02. Small -x behavior of the non-singlet and singlet structure functions g_1. https://arxiv.org/abs/hep-ph/0312029

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