Vacuum structure and flavor symmetry breaking in supersymmetric SO(nc) gauge theories

We determine the vacuum structure and phases of N = 1 theories obtained via a mass mu for the adjoint chiral superfield in N = 2, SO(n(c)) SQCD. For large number of flavors these theories have two groups of vacua. The first exhibits dynamical breaking of flavor symmetry USp(2n f) --> U(n f) and arises as a relevant deformation of a non-trivial superconformal theory. These are in the confined phase. The second group, in an IR-free phase with unbroken flavor symmetry, is produced from a Coulomb branch singularity with Seiberg's dual gauge symmetry. In the large-mu regime both groups of vacua are well-described by dual quarks and mesons, and dynamical symmetry breaking in the first group occurs via meson condensation. We follow the description of these vacua from weak to strong coupling and demonstrate a nontrivial agreement between the phases and the number of vacua in the two regimes. We construct the semiclassical monopole flavor multiplets and argue that their multiplicity is consistent with the number of N = 1 vacua. (C) 2001 Published by Elsevier Science B.V.