Supersymmetry breaking and gauge mediation in models with a generic superpotential

We present a general scheme for finding or creating a metastable vacuum in supersymmetric theories. By using the formalism, we show that there is a parameter region where a metastable vacuum exists in the Wess-Zumino model coupled to messenger fields. This model serves as a perturbative renormalizable model of direct gauge mediation.Comment: 13 pages, 1 figures. v2 two loop corrections and references added. to appear in PL

Gravitational Correction to Fuzzy String in Metastable Brane Configuration

We study dynamics of a cosmic string in a metastable brane configuration in Type IIA string theory. We first discuss a decay process of the cosmic string via a fuzzy brane (equivalently bubble/string bound state) by neglecting gravitational corrections in ten-dimension. We find that depending on the strength of the magnetic field induced on the bubble, the decay rate can be either larger or smaller than that of $O(4)$ symmetric bubble. Then, we investigate gravitational corrections to the fuzzy brane by using the extremal black $NS$-five brane solution, which makes the lifetime of the metastable state longer.Comment: 21 pages, 9 figure

Radiation of Supersymmetric Particles from Aharonov-Bohm R-string

We study radiation of supersymmetric particles from an Aharonov-Bohm string associated with a discrete R-symmetry. Radiation of the lightest supersymmetric particle, when combined with the observed dark matter density, imposes constraints on the string tension or the freeze-out temperature of the particle. We also calculate the amplitude for Aharonov-Bohm radiation of massive spin $3/2$ particles.Comment: 18 pages, 2 figures, v2: typos corrected,v3: section 3.2 and appendix B adde

Light Gauginos and Conformal Sequestering

In a wide class of direct and semi-direct gauge mediation models, it has been observed that the gaugino masses vanish at leading order. It implies that there is a hierarchy between the gaugino and sfermion masses, invoking a fine-tuning problem in the Higgs sector via radiative corrections. In this paper, we explore the possibility of solving this anomalously light gaugino problem exploiting strong conformal dynamics in the hidden sector. With a mild assumption on the anomalous dimensions of the hidden sector operators, we show that the next to leading order contributions to the gaugino masses can naturally be in the same order as the sfermion masses. \mu/B_\mu problem is also discussed.Comment: 17 pages, 1 figure. References adde

Metastable Vacua in Perturbed Seiberg-Witten Theories

We show that, for a generic choice of a point on the Coulomb branch of any N=2 supersymmetric gauge theory, it is possible to find a superpotential perturbation which generates a metastable vacuum at the point. For theories with SU(N) gauge group, such a superpotential can be expressed as a sum of single-trace terms for N=2 and 3. If the metastable point is chosen at the origin of the moduli space, we can show that the superpotential can be a single-trace operator for any N. In both cases, the superpotential is a polynomial of degree 3N of the vector multiplet scalar field.Comment: 22 pages, 4 figures; adding chiral ring arguments in appendix B.

Supersymmetry Breaking and Gauge Mediation

We review recent works on supersymmetry breaking and gauge mediation. We survey our current understanding of dynamical supersymmetry breaking mechanisms and describe new model building tools using duality, meta-stability, and stringy construction. We discuss phenomenological constraints and their solutions, paying attentions to issues with gaugino masses and electroweak symmetry breaking.Comment: 42 pages, 9 figures, invited review to appear in Annu. Rev. Nucl. Part. Sci. v2: references adde