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

Understand

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.