Dual conformal symmetry of 1-loop NMHV amplitudes in N=4 SYM theory

TL;DR

This paper proves that 1-loop NMHV superamplitudes in N=4 SYM theory exhibit dual conformal covariance for any number of external particles, providing explicit formulas and extending previous results.

Contribution

It establishes dual conformal covariance for all n in 1-loop NMHV amplitudes and derives explicit representations in terms of conformal cross-ratios.

Findings

All 1-loop NMHV superamplitudes are dual conformal covariant.

Explicit formulas for superamplitudes in terms of conformal cross-ratios.

Box coefficients from maximal cuts are also dual conformal covariant.

Abstract

We prove that 1-loop n-point NMHV superamplitudes in N=4 SYM theory are dual conformal covariant for all numbers n of external particles (after regularization and subtraction of IR divergences). This property was previously established for n < 10 in arXiv:0808.0491. We derive an explicit representation of these superamplitudes in terms of dual conformal cross-ratios. We also show that all the 1-loop `box coefficients' obtained from maximal cuts of N^kMHV n-point functions are covariant under dual conformal transformations.