Non-Abelian confinement via Abelian flux tubes in softly broken N=2 SUSY QCD

We study confinement in softly broken N = 2 SUSY QCD with gauge group SU(N-c) and N-f hypermultiplets of fundamental matter (quarks) when the Coulomb branch is lifted by small mass of adjoint matter. Concentrating mostly on the theory with SU(3) gauge group we discuss the N = 1 vacua which arise in the weak coupling at large values of quark masses and study flux tubes and monopole confinement in these vacua. In particular we find the BPS strings in SU(3) gauge theory formed by two interacting U(1) gauge fields and two scalar fields generalizing ordinary Abrikosov-Nielsen-Olesen vortices. Then we focus on the SU(3) gauge theories with N-f = 4 and Nf = 5 flavors with equal masses. In these theories there are V = 1 vacua with restored SU(2) gauge subgroup in quantum theory since SU(2) subsectors are not asymptotically free. We show that although the confinement in these theories is due to Abelian flux tubes the multiplicity of meson spectrum is the same as expected in a theory with non-Abelian confinement. (C) 2002 Published by Elsevier Science B.V.