Small x resummation in collinear factorisation

Understand

The summation of the small x-corrections to hard-scattering QCD amplitudes by collinear factorisation method is reconsidered and the K-factor is derived in leading ln x approximation with a result differing from the corresponding expression by Catani and Hautmann (Nucl.

• Phys.
• B 427, 475, 1994).
• The significance of the difference is demonstrated in the examples of structure function F_L and of exclusive vector meson electroproduction.