String Junctions and the BPS Spectrum of N=2 SU(2) Theory with Massive Matters

TL;DR

This paper investigates the BPS spectrum of four-dimensional N=2 SU(2) gauge theory with massive fundamental matter, using D3-brane probes to explicitly determine string web configurations and analyze the structure of marginal stability curves.

Contribution

It provides a detailed analysis of BPS string webs with multiple junctions and explains the nested structure of marginal stability curves in massive N=2 SU(2) theories.

Findings

Identification of BPS string webs with multiple junctions.

Explanation of nested marginal stability curves.

Explicit configurations of BPS states in massive theories.

Abstract

We study the BPS spectrum of four dimensional N=2 SU(2) theory with massive fundamental matters using the D3-brane probe. Since the BPS states are realized by string webs subject to the BPS conditions, we determine explicitly the configurations of such webs. It is observed that there appear BPS string webs with multiple of junctions corresponding to the fact that the curves of marginal stability in massive theory are infinitely nested. In terms of the string configurations, various properties of the curves of marginal stability are explained intuitively.