Phenomenological indications of the scale of supersymmetry

Electroweak precision measurements can provide indirect information about the possible scale of supersymmetry already at the present level of accuracy. We update the present-day sensitivities of precision data using mt 172.7±2.9 GeV for the experimental value of the top-quark mass, within the constrained minimal supersymmetric extension of the Standard Model (CMSSM), in which there are three independent soft supersymmetry-breaking parameters m1/2, m0 and A0. In addition to MW and sin2θeff, the analysis is based on (g-2)μ, BR(b→sγ) and the lightest MSSM Higgs boson mass, Mh. Assuming initially that the lightest supersymmetric particle (LSP) is a neutralino, we display the CMSSM results as functions of m1/2, fixing m0 so as to obtain the cold dark matter density allowed by WMAP and other cosmological data for specific values of A0, tan β and μ>0. For a sample value of tan β we analyze how the global χ2 function would change following a possible future evolution of the experimental central value of mt and its error. In a second step, we extend the analysis to other constrained versions of the MSSM: the NUHM in which the soft supersymmetry-breaking contributions to the Higgs masses are independent and the Higgs mixing parameter μ and the pseudoscalar Higgs mass MA become additional free parameters compared to the CMSSM, a VCMSSM in which the bilinear soft supersymmetry breaking parameter B0 = A0 - m0, and the GDM in which the LSP is the gravitino. In all scenarios we find indications for relatively light soft supersymmetry-breaking masses, offering good prospects for the LHC and the ILC, and in some cases also for the Tevatron