2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/189465We provide a manifestly N=2 supersymmetric formulation of the N=2 U(N_c) gauge model constructed in terms of N=1 superfields in hep-th/0409060. The model is composed of N=2 vector multiplets in harmonic superspace and can be viewed as the N=2 U(N_c) Yang-Mills effective action equipped with the electric and magnetic Fayet-Iliopoulos terms. We generalize this gauge model to an N=2 U(N_c) QCD model by introducing N=2 hypermultiplets in harmonic superspace which include both the fundamental representation of U(N_c) and the adjoint representation of U(N_c). The effect of the magnetic Fayet-Iliopoulos term is to shift the auxiliary field by an imaginary constant. Examining vacua of the model, we show that N=2 supersymmetry is spontaneously broken down to N=1.26 pages; typos fixed; version to appear in Nucl.Phys.B; eqn.(2.4) and typos correctedHigh Energy Physics - Theorytext