High-energy amplitudes in N=4 SYM in the next-to-leading order

TL;DR

This paper investigates the high-energy behavior of N=4 SYM amplitudes in the Regge limit, calculating the coefficient function for the pomeron in four-point correlators at next-to-leading order using Wilson line operator expansion.

Contribution

It provides the first calculation of the pomeron coefficient function for four $Z^2$ current correlators at NLO in perturbation theory within the Wilson-line OPE framework.

Findings

Pomeron intercept is universal and known at NLO.

Coefficient function for four $Z^2$ currents calculated at NLO.

Wilson-line OPE effectively computes high-energy amplitudes.

Abstract

The high-energy behavior of the N=4 SYM amplitudes in the Regge limit can be calculated order by order in perturbation theory using the high-energy operator expansion in Wilson lines. At large $N_c$, a typical four-point amplitude is determined by a single BFKL pomeron. The conformal structure of the four-point amplitude is fixed in terms of two functions: pomeron intercept and the coefficient function in front of the pomeron (the product of two residues). The pomeron intercept is universal while the coefficient function depends on the correlator in question. The intercept is known in the first two orders in coupling constant: BFKL intercept and NLO BFKL intercept calculated in Ref. 1. As an example of using the Wilson-line OPE, we calculate the coefficient function in front of the pomeron for the correlator of four $Z^2$ currents in the first two orders in perturbation theory.