Domain walls in supersymmetric QCD: The taming of the zoo

We provide a unified picture of the domain wall spectrum in supersymmetric QCD with Nc colors and Nf flavors of quarks in the (anti) fundamental representation. Within the framework of the Veneziano-Yankielowicz-Taylor effective Lagrangian, we consider domain walls connecting chiral symmetry breaking vacua, and we take the quark masses to be degenerate. For Nf/Nc<1/2, there is one BPS saturated domain wall for any value of the quark mass m. For 1/2<~Nf/Nc<1 there are two critical masses m* and m** which depend on the number of colors and flavors only through the ratio Nf/Nc. If m<m*, there are two BPS walls; if m*<m<m**, there is one non-BPS wall; and if m>m**, there is no domain wall. We numerically determine m* and m** as a function of Nf/Nc, and we find that m** approaches a constant value in the limit that this ratio goes to 1.