Subleading Regge limit from a soft anomalous dimension

TL;DR

This paper investigates subleading corrections in the Regge limit of massive scattering amplitudes in N=4 super Yang-Mills, revealing a simple power-law form governed by a Wilson loop anomalous dimension.

Contribution

It introduces a novel understanding of subleading Regge corrections using Wilson loop anomalous dimensions in a Higgsed N=4 SYM model, supported by three-loop calculations.

Findings

First power suppressed term is a simple power law

Exponent linked to Wilson loop with scalar insertion at the cusp

Proposes an exact high-energy total cross-section formula

Abstract

Wilson lines capture important features of scattering amplitudes, for example soft effects relevant for infrared divergences, and the Regge limit. Beyond the leading power approximation, corrections to the eikonal picture have to be taken into account. In this paper, we study such corrections in a model of massive scattering amplitudes in N = 4 super Yang-Mills, in the planar limit, where the mass is generated through a Higgs mechanism. Using known three-loop analytic expressions for the scattering amplitude, we find that the first power suppressed term has a very simple form, equal to a single power law. We propose that its exponent is governed by the anomalous dimension of a Wilson loop with a scalar inserted at the cusp, and we provide perturbative evidence for this proposal. We also analyze other limits of the amplitude and conjecture an exact formula for a total cross-section at high energies.