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arXiv · hep-ph/0307128

Running coupling effects for the singlet structure function g_1 at small x

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

The running of the QCD coupling is incorporated into the infrared evolution equations for the flavour structure function g_1. The explicit expressions for g_1 including the total resummation of the double-logarithmic contributions and accounting for the running coupling are obtained. We predict that asymptotically g_1 ~ x^{- Δ_S}, with the intercept Δ_S = 0.86, which is more than twice larger than the non-singlet intercept. The impact of the initial quark (δq) and gluon (δg) densities on the sign of g_1 at x << 1 is discussed and explicit expressions relating δq and δg are obtained.

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B. I. Ermolaev, M. Greco, S. I. Troyan. 2003-11-18. Running coupling effects for the singlet structure function g_1 at small x. https://doi.org/10.1016/j.physletb.2003.11.016

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