相关论文: Constraints on Trilinear Coupling Constant A_0 in …
In the present work we search for renormalization group invariant relations among the various massless and massive parameters of the Minimal Supersymmetric Standard Model. We find that indeed several of the previously free parameters of the…
In the Higgs sector of the Minimal Supersymmetric Standard Model, the mass of the pseudoscalar $A$ is an independent parameter together with $\tan \beta \equiv v_2/v_1$. If $m_A$ is small, then the process $e^+ e^- \to h + A$ is…
Renormalization group analysis is made on the relation $m_{\rm H} \simeq \sqrt{2}m_t$ for masses of the top quark and the Higgs boson, which is predicted by the standard model based on generalized covariant derivatives with gauge and Higgs…
If N=2 supersymmetry breaks to N=1 supersymmetry at an intermediate scale $m_2$ and then, later on, N=1 supersymmetry breaks and produces standard model at a scale $m_{susy}$ such that $m_2 > m_{susy}$, renormalization group evolution of…
We discuss a possibility of restricting parameters in $\mathcal{N}=2$ supergravity based on axion observations. We derive conditions that prepotential and gauge couplings should satisfy. Such conditions not only allow us to constrain the…
It is possible to place constraints on non-Standard-Model gauge-boson self-couplings and other new physics by studying their one-loop contributions to precisely measured observables. We extend previous analyses which constrain such…
We study the effect of integrating out the heavy fields in a supersymmetric GUT which does not contain small mass parameters in the limit of exact supersymmetry. The trilinear ($A$) and bilinear ($B$) coefficients of the supersymmetry…
A global analysis is performed using the latest data from LEP and SLC. Constraints on the electroweak universal parameters ($S,T,U$) and on the masses of the top quark and Higgs boson within the Standard Model (SM) are investigated. The…
We study the stability constraints on the parameter space of a triplet extension of MSSM. Existence of unbounded from below directions in the potential can spoil successful Electroweak (EW) symmetry breaking by making the corresponding…
Non-Abelian gauge theories may have continuum limits in more than four dimensions, supported by non-trivial ultra-violet fixed points. Moreover, such theories can be expected to be accessible to Wilson's epsilon expansion. We investigate…
If there is no the Standard Model Higgs boson, the interaction among the gauge bosons becomes strong at high energies (~ 1TeV). The effects of strong electroweak symmetry breaking could manifest themselves indirectly through the vertices as…
We present an orbifold GUT model in which the NMSSM Higgs trilinear couplings are unified with the three Standard Model gauge couplings. The model is constructed as an N=2 supersymmetric SU(8) gauge theory in six dimensions, which is…
The status of coupling constant unification (with and without a unification of Yukawa couplings) is discussed. Uncertainties associated with the input coupling constants, $m_{b}$ and $m_{t}$, threshold corrections at the low and high scale,…
The trilinear Higgs coupling $\lambda_{hhh}$ is a crucial tool to probe the structure of the Higgs potential and to search for possible effects of physics beyond the Standard Model (SM). Focusing on the Two-Higgs-Doublet Model as a concrete…
In supersymmetric models extended with a gauge singlet the mass of the lightest Higgs boson has contributions proportional to the adimensional coupling $\lambda$. In minimal scenarios, the requirement that this coupling remains perturbative…
We investigate the general two Higgs doublet model imposing both the unitarity conditions and the bounded-from-below conditions. Both types of conditions restrict the ranges of the parameters of the scalar potential. We study the model in…
We present the simplest, string-derivable, supergravity model and discuss its experimental consequences. This model is a new string-inspired flipped $SU(5)$ which unifies at the string scale $M_U=10^{18}\GeV$ due to the introduction of an…
The standard model extended by three vector-like families with masses of order 1 TeV -- 100 TeV allows for unification of gauge couplings. The values of gauge couplings at the electroweak scale are highly insensitive to fundamental…
The scale invariant of the effective potential of the standard model at two-loop is used as a boundary condition under the assumption that the two-loop effective potential approximates the full effective potential. This condition leads with…
For the three-dimensional cubic model, the nonlinear susceptibilities of the fourth, sixth, and eighth orders are analyzed and the parameters \delta^(i) characterizing their reduced anisotropy are evaluated at the cubic fixed point. In the…