Effective action of beta-deformed N = 4 SYM theory: Farewell to two-loop BPS diagrams

Sergei M. Kuzenko, Ian N. McArthur

Within the background field approach, all two-loop sunset vacuum diagrams, which occur in the Coulomb branch of N = 2 superconformal theories(including N = 4 SYM), obey the BPS con…