Singular points in N=2 SQCD

TL;DR

This paper analyzes the structure of singular points in N=2 SQCD with classical gauge groups, revealing the low-energy physics involves superconformal sectors and an infrared free SU(2) gauge group, especially when softly breaking to N=1.

Contribution

It applies a recent technique to identify the low-energy physics at singular points in N=2 SQCD, including the emergence of superconformal sectors coupled to an IR free SU(2) gauge group.

Findings

Maximally singular points involve two superconformal sectors coupled to an IR free SU(2) gauge group.

In USp and SO gauge groups, one sector is always free, unlike in SU cases.

Adding a mass term leads to a finite number of confining vacua.

Abstract

We revisit the study of singular points in N=2 SQCD with classical gauge groups. Using a technique proposed recently by Gaiotto, Seiberg and Tachikawa we find that the low-energy physics at the maximally singular point involves two superconformal sectors coupled to an infrared free SU(2) gauge group. When one softly breaks extended supersymmetry to N=1 adding a mass term for the chiral multiplet in the adjoint representation, a finite number of vacua remain and the theory becomes confining. Our analysis allows to identify the low-energy physics at these distinguished points in the moduli space. In some cases, which we will describe in detail, two sectors coupled to an infrared free SU(2) gauge group emerge as before. For USp and SO gauge groups one of these sectors is always free, contrary to the SU case.