Proof of the Dual Conformal Anomaly of One-Loop Amplitudes in N = 4 SYM

We provide two derivations of the one-loop dual conformal anomaly of generic npoint superamplitudes in maximally supersymmetric Yang-Mills theory. Our proofs are based on simple applications of unitarity, and the known analytic properties of the amplitudes. 1 {a.brandhuber, p.j.heslop, g.travaglini}@qmul.ac.uk