1388004
Low-scale anomalous U(1) and decoupling solution to supersymmetric flavor problem
Abstract Supersymmetric standard models where the ultraviolet cut-off scale is only a few orders of magnitude higher than the electroweak scale are considered. Phenomenological consequences of this class of models are expected to be very different from, for example, the conventional supergravity scenario. We apply this idea to a model with an anomalous U(1) gauge group and construct a viable model in which some difficulties of the decoupling solution to the supersymmetric flavor problem are ameliorated.
2040672
Radiative corrections to a supersymmetric relation: A new approach
Recently it has been realized that the production and decay processes of charginos, neutralinos, and sleptons receive corrections which grow like logm{sub {tilde q}} for large m{sub {tilde q}}. In this paper we calculate the chargino pair production cross section at e{sup +}e{sup {minus}} colliders with quark-squark loop corrections. We introduce a novel formulation, where the one-loop amplitude is reorganized into two parts. One part is expressed in terms of the {open_quotes}effective{close_quotes} chargino coupling {bar g}{sub e{tilde {nu}}{tilde W}} and mixing matrices U{sup P},V{sup P}, and includes all O(logm{sub {tilde q}}) corrections, while the other decouples for large m{sub {tilde q}}. The form of the one-loop cross section then becomes physically transparent. Our formulation can be easily extended to other loops and processes. Numerically, we find significant corrections due to the effective t-channel coupling {bar g}{sub e{tilde {nu}}{tilde W}}, for gaugino-like charginos. In the mixed region, where the chargino has large gaugino and Higgsino components, the corrections due to (U{sup P},V{sup P}) are also significant. Our numerical results disagree with a previous calculation. We reexamine previous studies of the determination of {bar g}{sub e{tilde {nu}}{tilde W}} through the measurement of the chargino production cross section. We point out that amore » previous study, which claimed that the measurement suffers large systematic errors, was performed at a {open_quotes}pessimistic{close_quotes} point in MSSM parameter space. We provide reasons why the systematic errors are not a limiting factor for generic parameter choices. {copyright} {ital 1998} {ital The American Physical Society}« less
16212962
Motivations for and implications of nonuniversal GUT scale boundary conditions for soft SUSY breaking parameters
We outline several well-motivated models in which GUT boundary conditions for SUSY breaking are non-universal. The diverse phenomenological implications of the non-universality for SUSY discovery at LEP2, the Tevatron, the LHC and the NLC are sketched.
17333378
SUSY - QCD corrections to top and bottom squark decays into Higgs bosons
We calculate the $\mathcal{O}({\ensuremath{\alpha}}_{s})$ SUSY-QCD corrections to the widths of top and bottom squark decays into Higgs bosons within the minimal supersymmetric standard model. We give the complete analytical formulas, paying particular attention to the on-shell renormalization of the soft SUSY-breaking parameters. We also perform a detailed numerical analysis of both top and bottom squark decays into all Higgs bosons ${h}^{0},$ ${H}^{0},$ ${A}^{0},$ and ${H}^{\ifmmode\pm\else\textpm\fi{}}.$ We find that the SUSY-QCD corrections are significant, mostly negative, and of the order of a few ten percent.
11356307
Two-loop renormalization of gaugino masses in general supersymmetric gauge models.
We calculate the two-loop renormalization group equations for the running gaugino masses in general supersymmetry (SUSY) gauge models, improving our previous result. We also study its consequences on the unification of the gaugino masses in the SUSY SU(5) model. The two-loop correction to the one-loop relation [ital m][sub [ital i]]([mu])[proportional to][alpha][sub [ital i]]([mu]) is found to be of the order of a few percent.
16486262
SUSY--QCD Corrections to Higgs Particle Decays into Quarks and Squarks
We study the decays of the Higgs bosons $H^{\pm}$, $H^0$, and $A^0$ within the Minimal Supersymmetric Standard Model. For decays into quarks and squarks we include the supersymmetric QCD radiative corrections. We find that the corrections are significant and can go up to 50%. The supersymmetric decay modes $H^+ \to \tilde t \bar{\tilde b}$ and $H^0 (A^0) \to \tilde t \bar{\tilde t}$ can be dominant in a wide range of the model parameters due to the large Yukawa couplings and mixings of $\tilde t$ and $\tilde b$.
44450900
Illustrating SUSY breaking effects on various inflation mechanisms
A bstractWe consider the supersymmetry breaking effects on typical inflation models with different types of Kähler potential. The critical size of supersymmetry-breaking scale, above which the flatness of the inflaton potential is spoiled, drastically changes model by model. We present the universal description of such effects in terms of a field-dependent scaling factor by which gravity-mediated supersymmetry breaking terms are suppressed or enhanced, based on the conformal supergravity framework. Such a description would be useful when we estimate them in constructing supersymmetric models of particle cosmology.