Rise of the DIS structure function F_L at small x caused by double-logarithmic contributions

TL;DR

This paper demonstrates that double-logarithmic contributions cause a power-like rise of the structure function F_L at small x, highlighting the importance of resummed higher-order effects in quantum chromodynamics.

Contribution

It introduces a calculation of F_L in the double-logarithmic approximation showing the combined effect of 1/x factors and resummed contributions leading to a rise at small x.

Findings

F_L exhibits a power-like increase at small x.

Double-logarithmic effects are crucial for understanding F_L behavior.

Resummation of higher orders enhances the rise of F_L.

Abstract

We present calculation of F_L in the double-logarithmic approximation and demonstrate that the synergic effect of the factor 1/x from the \alpha_s^2-order and the steep x-dependence of the totally resummed double logarithmic contributions of higher orders ensures the power-like rise of F_L at small x and arbitrary Q^2.