Instanton effects in N=1 brane models and the Kahler metric of twisted matter

TL;DR

This paper investigates instanton effects in N=1 brane models with magnetized D9 branes on orbifolds, revealing how Euclidean 5 branes influence the superpotential and providing insights into the Kahler metric of twisted matter.

Contribution

It introduces a detailed analysis of instanton effects from Euclidean 5 branes in magnetized D-brane models, connecting annuli diagrams to the Kahler metric of twisted matter.

Findings

Euclidean 5 branes generate superpotential contributions like ADS/TVY.

The interplay between annuli diagrams and holomorphicity constrains the effective action.

Results provide new insights into the Kahler metric of twisted matter multiplets.

Abstract

We consider locally consistent systems of magnetized D9 branes on an orbifolded six-torus which support N=1 gauge theories. In such realizations, the matter multiplets arise from "twisted" strings connecting different stacks of branes. The introduction of Euclidean 5 branes (E5) wrapped on the six-dimensional compact space leads to instanton effects. For instance, if the system is engineered so as to yield SQCD, a single E5 brane may account for the ADS/TVY superpotential. We discuss the subtle interplay that exists between the annuli diagrams with an E5 boundary and the holomorphicity properties of the effective low-energy action of the N=1 theory. The consistency of this picture allows to obtain information on the Kahler metric of the chiral matter multiplets arising from twisted strings.