Related papers: Threshold Corrections in the Exceptional Supersymm…
The Standard Model global fit to precision data is excellent. The Minimal Supersymmetric Standard Model can also fit the data well, though not as well as the Standard Model. At best, supersymmetric contributions either decouple or only…
High precision measurements of electroweak observables at $e^\pm$ colliders indicate the existence of a light Higgs boson below the $W^\pm$ threshold. If such a fundamental scalar should be found in the near future it is important to fully…
We analyze the parametric space of the constrained minimal supersymmetric standard model with mu>0 supplemented by a generalized asymptotic Yukawa coupling quasi-unification condition which yields acceptable masses for the fermions of the…
We embed a theory with Zprime gauge boson (related to extra U(1) gauge group) into a supersymmetric GUT theory based on SO(10). Two possible sequences of SO(10) breaking via VEVs of appropriate Higgs fields are considered. Gauge coupling…
We study the Higgs-boson mass spectrum of the minimal supersymmetric standard model, in which the tree-level CP invariance of the Higgs potential is broken explicitly by loop effects of soft-CP-violating Yukawa interactions related to…
Constraint on spin-dependent and spin-independent Yukawa potential at atomic scale is developed. That covers constraints on a coupling constant of an additional photon $\gamma^*$ and a pseudovector boson. The mass range considered is from…
In supersymmetric models with minimal particle content and without large left-right squarks mixing, the conventional knowledge is that the Higgs Boson mass around 125 GeV leads to top squark masses ${\cal O}(10)$ TeV, far beyond the reach…
We compute one-loop corrections to the mass matrix of the neutral Higgs bosons of the Minimal Supersymmetric Standard Model with explicit CP violation. We use the effective potential method, allowing for arbitrary splitting between squark…
We show that if the Standard Model gauge fields and fermions propagate in extra dimenions, a composite Higgs field with the correct quantum number can arise naturally as a bound state due to the strong gauge interactions in higher…
The Minimal supersymmetric extension of the Standard Model (MSSM) with light stops, charginos or pseudoscalar Higgs bosons has been suggested as an explanation of the too high value of the branching ratio of the Z0 boson into b quarks (Rb…
The large top Yukawa coupling results in the top quark contributing significantly to the quantum correction of the Higgs mass term. Traditionally, this effect is canceled by the presence of top partners in symmetry-based models. However,…
We calculate the Yukawa corrections of order ${\cal O}(\alpha_{ew}m_{t(b)}^2/m_W^2)$, ${\cal O}(\alpha_{ew}m_{t(b)}^3/m_W^3)$ and ${\cal O}(\alpha_{ew}m_{t(b)}^4/m_W^4)$ to the widths of the decays $\tilde t_2\to \tilde t_1 + (h^0,H^0,A^0)$…
We study the low energy evolution of coupling constants of the standard model and show that gauge coupling unification can be achieved at the electroweak scale with a suitable normalization. We choose the grand unification group to be the…
We systematically study the modifications in the couplings of the Higgs boson, when identified as a pseudo Nambu-Goldstone boson of a strong sector, in the light of LHC Run 1 and Run 2 data. For the minimal coset SO(5)/SO(4) of the strong…
The presence of new matter fields charged under the Standard Model gauge group at intermediate scales below the Grand Unification scale modifies the renormalization group evolution of the gauge couplings. This can in turn significantly…
We perform global fits to the parameters of the Constrained Minimal Supersymmetric Standard Model (CMSSM) and to a variant with non-universal Higgs masses (NUHM1). In addition to constraints from low-energy precision observables and the…
We perform global fits of the Higgs boson couplings to the full Higgs datasets collected at the LHC with the integrated luminosities per experiment of approximately 5/fb at 7 TeV, 20/fb at 8 TeV, and up to 139/fb at 13 TeV. Our combined…
We study the deviation of yukawa coupling in the gauge-Higgs unification scenario from the Standard Model one. Taking into account the brane mass terms necessary for generating the flavor mixing and removing the exotic massless fermions, we…
We present a Z_6 orbifold compactification of the E_8xE_8 heterotic string which leads to the (supersymmetric) Standard Model gauge group and matter content. The quarks and leptons appear as three 16-plets of SO(10), whereas the Higgs…
The considerable part of the parameter space in the MSSM corresponding to the infrared quasi fixed point scenario is excluded by LEP II bounds on the lightest Higgs boson mass. In the NMSSM the mass of the lightest Higgs boson reaches its…