Mechanisms of Supersymmetry Breaking in the MSSM

Preliminary Remarks. Gauge mediated supersymmetry breaking. Gravity mediated supersymmetry breaking. Anomaly mediated supersymmetry breaking. Gaugino mediated supersymmetry breaking. Braneworld supersymmetry breaking. Conclusions.Comment: New references added, minor misprints corrected, text otherwise unchange

Duality in the Presence of Supersymmetry Breaking

We study Seiberg duality for N=1 supersymmetric QCD with soft supersymmetry-breaking terms. We generate the soft terms through gauge mediation by coupling two theories related by Seiberg duality to the same supersymmetry-breaking sector. In this way, we know what a supersymmetry-breaking perturbation in one theory maps into in its ``dual''. Assuming a canonical Kahler potential we calculate the soft terms induced in the magnetic theory and find that some of the scalars acquire negative masses squared. If duality is still good for small supersymmetry breaking, this may imply some specific symmetry breaking patterns for supersymmetric QCD with small soft supersymmetry-breaking masses, in the case that its dual theory is weakly coupled in the infrared. In the limit of large supersymmetry breaking, the electric theory becomes ordinary QCD. However, the resulting symmetry breaking in the magnetic theory is incompatible with that expected for QCD.Comment: 27 pages, LaTex, minor changes, version to appear in Nucl. Phys.

Lectures on Supersymmetry Breaking

We review the subject of spontaneous supersymmetry breaking. First we consider supersymmetry breaking in a semiclassical theory. We illustrate it with several examples, demonstrating different phenomena, including metastable supersymmetry breaking. Then we give a brief review of the dynamics of supersymmetric gauge theories. Finally, we use this dynamics to present various mechanisms for dynamical supersymmetry breaking. These notes are based on lectures given by the authors in 2007, at various schools.Comment: 47 pages. v2: minor correction

Supersymmetry Breaking, R-Symmetry Breaking and Metastable Vacua

Models of spontaneous supersymmetry breaking generically have an R-symmetry, which is problematic for obtaining gaugino masses and avoiding light R-axions. The situation is improved in models of metastable supersymmetry breaking, which generically have only an approximate R-symmetry. Based on this we argue, with mild assumptions, that metastable supersymmetry breaking is inevitable. We also illustrate various general issues regarding spontaneous and explicit R-symmetry breaking, using simple toy models of supersymmetry breaking.Comment: 23 page

Supersymmetry breaking

These lectures provide a simple introduction to supersymmetry breaking. After presenting the basics of the subject and illustrating them in tree-level examples, we discuss dynamical supersymmetry breaking, emphasizing the role of holomorphy and symmetries in restricting dynamically-generated superpotentials. We then turn to mechanisms for generating the MSSM supersymmetry-breaking terms, including ``gravity mediation'', gauge mediation, and anomaly mediation. We clarify some confusions regarding the decoupling of heavy fields in general and D-terms in particular in models of anomaly-mediation.Comment: 26 pages. Lectures given at the Les Houches Summer School (Session LXXXIV) on ``Particle Physics Beyond the Standard Model'', Les Houches, France, August 1-26, 200

Sparticle spectrum and constraints in anomaly mediated supersymmetry breaking models

We study in detail the particle spectrum in anomaly mediated supersymmetry breaking models in which supersymmetry breaking terms are induced by the super-Weyl anomaly. We investigate the minimal anomaly mediated supersymmetry breaking models, gaugino assisted supersymmetry breaking models, as well as models with additional residual nondecoupling D-term contributions due to an extra U(1) gauge symmetry at a high energy scale. We derive sum rules for the sparticle masses in these models which can help in differentiating between them. We also obtain the sparticle spectrum numerically, and compare and contrast the results so obtained for the different types of anomaly mediated supersymmetry breaking models.Comment: LaTeX, 20 pages, 6 figures. A few comments and a reference added; typos corrected; version published in Phys. Rev.

Supersymmetry and Electroweak Breaking in the Interval

Hypermultiplets are considered in the five-dimensional interval where all fields are continuous and the boundary conditions are dynamically obtained from the action principle. The orbifold boundary conditions are obtained as particular cases. We can interpret the Scherk-Schwarz supersymmetry breaking as a misalignment of boundary conditions while a new source of supersymmetry breaking corresponding to a mismatch of different boundary parameters is identified. The latter can be viewed as coming from boundary supersymmetry breaking masses for hyperscalars and the nature of the corresponding supersymmetry breaking parameter is analyzed. For some regions of the parameter space where supersymmetry is broken (either by Scherk-Schwarz boundary conditions or by boundary hyperscalar masses) electroweak symmetry breaking can be triggered at the tree level.Comment: 28 pages, 5 figure

Gauge/Anomaly Syzygy and Generalized Brane World Models of Supersymmetry Breaking

In theories in which SUSY is broken on a brane separated from the MSSM matter fields, supersymmetry breaking is naturally mediated in a variety of ways. Absent other light fields in the theory, gravity will mediate supersymmetry breaking through the conformal anomaly. If gauge fields propagate in the extra dimension they, too, can mediate supersymmetry breaking effects. The presence of gauge fields in the bulk motivates us to consider the effects of new messenger fields with holomorphic and non-holomorphic couplings to the supersymmetry breaking sector. These can lead to contributions to the soft masses of MSSM fields which dramatically alter the features of brane world scenarios of supersymmetry breaking. In particular, they can solve the negative slepton mass squared problem of anomaly mediation and change the predictions of gaugino mediation.Comment: 4 pages, RevTe

Soft supersymmetry-breaking terms from supergravity and superstring models

We review the origin of soft supersymmetry-breaking terms in N=1 supergravity models of particle physics. We first consider general formulae for those terms in general models with a hidden sector breaking supersymmetry at an intermediate energy scale. The results for some simple models are given. We then consider the results obtained in some simple superstring models in which particular assumptions about the origin of supersymmetry breaking are made. These are models in which the seed of supersymmetry breaking is assumed to be originated in the dilaton/moduli sector of the theory.Comment: 24 pages, to appear in the book `Perspectives on Supersymmetry', World Scientific, Editor G. Kane; some comments and references adde