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The Background Field Method for N = 2 Super Yang-Mills Theories in Harmonic Superspace

I. L. Buchbinder·E. I. Buchbinder·S. M. Kuzenko·B. A. Ovrut
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Abstract

The background field method for N=2 super Yang-Mills theories in harmonic superspace is developed. The ghost structure of the theory is investigated. It is shown that the ghosts include two fermionic real omega-hypermultiplets (Faddeev-Popov ghosts) and one bosonic real omega-hypermultiplet (Nielsen-Kallosh ghost), all in the adjoint representation of the gauge group. The one-loop effective action is analysed in detail and it is found that its structure is determined only by the ghost corrections in the pure super Yang-Mills theory. As applied to the case of N=4 super Yang-Mills theory, realized in terms of N=2 superfields, the latter result leads to the remarkable conclusion that the one-loop effective action of the theory does not contain quantum corrections depending on the N=2 gauge superfield only. We show that the leading low-energy contribution to the one-loop effective action in the N=2 SU(2) super Yang-Mills theory coincides with Seiberg's perturbative holomorphic effective action.

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I. L. Buchbinder, E. I. Buchbinder, S. M. Kuzenko, B. A. Ovrut. 1997-04-30. The Background Field Method for N = 2 Super Yang-Mills Theories in Harmonic Superspace. https://doi.org/10.1016/s0370-2693(97)01319-1

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