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Analytic Approximation to the GLAP evolution of $F_2(x,Q^2)$ in the small-$x$ region

L. Mankiewicz·A. Saalfeld·T. Weigl
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Abstract

We propose a systematic approximation scheme for solving GLAP evolution equations at small Bjorken-$x$. The approximate solutions interpolate smoothly between hard (singular as $x^{-(1+λ)}$, $λ> 0$) and soft (singular at most as $x^{-1}$) initial conditions and may be applied in a wide range of $Q^2$. The small-$x$ behavior of $F_2^p(x,Q^2)$ which is extracted from a fit to HERA data agrees with results from a global fit.

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L. Mankiewicz, A. Saalfeld, T. Weigl. 1997-06-11. Analytic Approximation to the GLAP evolution of $F_2(x,Q^2)$ in the small-$x$ region. https://arxiv.org/abs/hep-ph/9706330

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