High-energy Operator Product Expansion at sub-eikonal level

Abstract

The high energy Operator Product Expansion for the product of two electromagnetic currents is extended to the sub-eikonal level in a rigorous way. I calculate the impact factors for polarized and unpolarized structure functions, define new distribution functions, and derive the evolution equations for unpolarized and polarized structure functions in the flavor singlet and non-singlet case.

Comments: 82 pages, 16 figures, JHEP version with typos corrected, references added