D-instanton derivation of multi-fermion F-terms in supersymmetric QCD

TL;DR

This paper derives multi-fermion F-terms in supersymmetric QCD using D-instantons in string theory, confirming previous results for SU(2) and extending to symplectic groups, thereby elucidating instanton effects on moduli space deformation.

Contribution

It provides a string theory derivation of multi-fermion F-terms in SQCD, including new results for symplectic gauge groups, linking D-instanton effects to field theory instantons.

Findings

Derived multi-fermion F-terms from D-instantons in SQCD.

Confirmed agreement with previous results for SU(2).

Extended analysis to symplectic gauge groups showing moduli space deformation.

Abstract

We investigate effects of field theory instantons by considering D-instantons in a suitable D3-brane background. In supersymmetric QCD with SU(N_c) gauge group with N_f=N_c flavors, the moduli space of vacua is deformed by instantons. This effect can be described by the chiral interactions which are called multi-fermion F-terms. We derive these chiral interaction terms as D-instanton effects in the presence of D3-branes. For SU(2), the obtained result agrees with the previous result worked out by Beasley and Witten [hep-th/0409149]. We also explicitly work out those for the case of the symplectic gauge group, and show that they describe the deformation of the moduli space.