Dynamical supersymmetry breaking, with flavor

We explore calculable models with low-energy supersymmetry where the flavor hierarchy is generated by quark and lepton compositeness, and where the composites emerge from the same sector that dynamically breaks supersymmetry. The observed pattern of standard model fermion masses and mixings is obtained by identifying the various generations with composites of different dimension in the ultraviolet. These “single-sector” supersymmetry-breaking models give rise to various spectra of soft masses which are, in many cases, quite distinct from what is commonly found in models of gauge or gravity mediation. In typical models which satisfy all flavor-changing neutral current constraints, both the first- and second-generation sparticles have masses of order 20 TeV, while the stop mass is a few TeV. In other cases, all sparticles obtain masses of order a few TeV predominantly from gauge mediation, even though the first two generations are composite.

Figure 1

Constraints on first and second-generation sfermion masses. Light gray region ruled out by $K-\overline{K}$-mixing. (a) Dark gray region ruled out by tachyonic stops at the weak scale [$m_{\tilde{t}}(1\mathrm{TeV})<0$]. We assumed $m_{\tilde{g}}=500\mathrm{GeV}$, $m_{\tilde{t}}(100\mathrm{TeV})=1\mathrm{TeV}$. Note that the stop mass constraint disappears completely for the $m_{{\tilde{f}}_1}$ and $m_{{\tilde{f}}_2}$ mass range shown when $m_{\tilde{t}}(100\mathrm{TeV})\gtrsim 1.6\mathrm{TeV}$. (b) Dark gray region ruled out by stops being too light at the weak scale to give a Higgs mass above LEP limits [$m_{\tilde{t}}(1\mathrm{TeV})\lesssim 1000\mathrm{GeV}$, assuming the trilinear coupling is negligible]. We assumed $m_{\tilde{g}}=500\mathrm{GeV}$, $m_{\tilde{t}}(100\mathrm{TeV})=1.6\mathrm{TeV}$.