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arXiv · hep-ph/9408377

Small $x$ Contributions to the Structure Function $F_L(x,Q^2)$

Johannes Blümlein
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Abstract

The gluon contributions to $F_L(x,Q^2)$ in ${\cal O}(α_s)$ are calculated taking into account the transverse momentum of the initial state parton. In comparison with collinear factorization $F_L(x,Q^2)$, is not affected at large $x$ but takes smaller values in the small $x$ range. The onset of the $k_{\perp}$ effect is a function of $Q^2$.

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Johannes Blümlein. 1994-08-26. Small $x$ Contributions to the Structure Function $F_L(x,Q^2)$. https://doi.org/10.1016/0920-5632(95)00035-8

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