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arXiv · hep-th/9703147

Effective Action of the N = 2 Maxwell Multiplet in Harmonic Superspace

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

We present, in the N=2, D=4 harmonic superspace formalism, a general method for constructing the off-shell effective action of an N=2 abelian gauge superfield coupled to matter hypermultiplets. Using manifestly N=2 supersymmetric harmonic supergraph techniques, we calculate the low-energy corrections to the renormalized one-loop effective action in terms of N=2 (anti)chiral superfield strengths. For a harmonic gauge prepotential with vanishing vacuum expectation value, corresponding to massless hypermultiplets, the only non-trivial radiative corrections to appear are non-holomorphic. For a prepotential with non-zero vacuum value, which breaks the U(1)-factor in the N=2 supersymmetry automorphism group and corresponds to massive hypermultiplets, only non-trivial holomorphic corrections arise at leading order. These holomorphic contribution are consistent with Seiberg's quantum correction to the effective action, while the first non-holomorphic contribution in the massless case is the N=2 supersymmetrization of the Heisenberg-Euler effective Lagrangian.

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I. L. Buchbinder, E. I. Buchbinder, E. A. Ivanov, S. M. Kuzenko, B. A. Ovrut. 1997-03-28. Effective Action of the N = 2 Maxwell Multiplet in Harmonic Superspace. https://doi.org/10.1016/s0370-2693(97)01025-3

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