Exact propagators in harmonic superspace

TL;DR

This paper derives exact propagators in harmonic superspace for N=2 super Yang-Mills theories, simplifying calculations of quantum corrections and enabling multi-loop computations in supersymmetric gauge theories.

Contribution

It provides the first exact expressions for propagators with a covariantly constant background, enhancing multi-loop quantum correction calculations in N=2 supersymmetric theories.

Findings

Exact propagators for covariantly constant background vector multiplet.

Simplification of harmonic superspace dependence in on-shell cases.

Facilitates efficient multi-loop quantum correction computations.

Abstract

Within the background field formulation in harmonic superspace for quantum N = 2 super Yang-Mills theories, the propagators of the matter, gauge and ghost superfields possess a complicated dependence on the SU(2) harmonic variables via the background vector multiplet. This dependence is shown to simplify drastically in the case of an on-shell vector multiplet. For a covariantly constant background vector multiplet, we exactly compute all the propagators. In conjunction with the covariant multi-loop scheme developed in hep-th/0302205, these results provide an efficient (manifestly N = 2 supersymmetric) technical setup for computing multi-loop quantum corrections to effective actions in N = 2 supersymmetric gauge theories, including the N = 4 super Yang-Mills theory.