Related papers: Global Electroweak Fits and Gauge Coupling Unifica…
We reanalyze precision LEP data and coupling constant unification in the minimal supersymmetric $SU(5)$ model including the evolution of the gaugino masses. We derive general bounds on the primordial gaugino supersymmetry-breaking…
The ununified standard model is an extension of the standard model that contains separate electroweak gauge groups for quarks and leptons. When it was originally proposed, data allowed the new gauge bosons to be quite light. We use recent…
The Next to Minimal Supersymmetric Standard Model (NMSSM) with a Higgs-singlet coupling {\lambda} close to unity, moderate tan {\beta} and stop masses below 1 TeV minimizes the fine tuning of the electroweak scale, making possible that the…
In view of the recent measurement of the muon g-2 and finalization of the LEP electroweak data, we re-examine all the new particle contributions to those observables in the MSSM. The SM fits the latest electroweak data excellently with the…
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 radiative electroweak symmetry breaking, the b-\tau Yukawa and gauge couplings unification in the MSSM and its SU(5) extensions are studied in detail. In the framework of the two-loop renormalization group equations both low- and…
Motivated by the coupling unification problem, we propose a novel extension of the Minimal Supersymmetric Standard Model. One of the predictions of this extension is existence of new states neutral under SU(3)_c X SU(2)_w but charged under…
It is challenging to explain the tentative 125 GeV Higgs signal in the Minimal Supersymmetric Standard Model (MSSM) without introducing excessive fine-tuning, and this motivates the study of non-minimal implementations of low energy…
We study the electroweak symmetry breaking in a five dimensional $Sp(6)$ gauge-Higgs unification model where the weak mixing angle is predicted to be $\sin^2 \theta_W=1/4$ at the compactification scale. We find that the correct pattern of…
The prediction of the strong coupling assuming (supersymmetric) coupling constant unification is reexamined. We find, using the new electroweak data, $\alpha_{s}(M_{Z}) \approx 0.129 \pm 0.010$. The implications of the large $\alpha_{s}$…
We present selected results of our program to determine the masses, gauge couplings, and Yukawa couplings of the minimal supersymmetric model in a full one-loop calculation. We focus on the precise prediction of the strong coupling…
We perform a detailed analysis of the next-to-minimal supersymmetric standard model (NMSSM), imposing the constraints of two-loop gauge coupling unification, universal soft supersymmetry breaking and the correct pattern of electroweak…
In this letter, we study collider phenomenology in the supersymmetric Standard Model with a certain type of non-universal gaugino masses at the gauge coupling unification scale, motivated by the little hierarchy problem. In this scenario,…
We will explore the consequences on the electroweak breaking condition, the mass of supersymmetric partners and the scale at which supersymmetry is broken, for arbitrary values of the supersymmetric parameters tan(beta) and the stop mixing…
We analyze the implications of electroweak and strong coupling unification in a very general class of models extending the minimal supersymmetric standard model in $4+p$ dimensions $(p\geq 0)$. In general, electroweak precision data require…
In the light of the gathering evidence for $\nu_{\mu}-\nu_{\tau}$ neutrino oscillations, coming in particular from the Super-Kamiokande data on atmospheric neutrinos, we re-analyze the unification of gauge and Yukawa couplings within the…
We study the gauge coupling unification of the minimal supersymmetric standard model with non-universal soft scalar and gaugino masses. The unification scale of the gauge couplings is estimated for non-universal cases. It is sensitive to…
Within the framework of supersymmetric grand unification, estimates of the $b$ quark mass based on the asymptotic relation $m_b \simeq m_\tau$ single out the region with $\tan\beta$ close to unity, particularly if $m_t(m_t)…
We show how gauge coupling unification near the Planck scale $M_P\sim 10^{19}$ GeV can be achieved in the framework of supersymmetry, facilitating a full unification of all forces with gravity. Below the conventional GUT scale $M_{GUT}\sim…
We discuss the fine-tuning issue within the MSSM framework. Following the idea that the fine-tuning can measure effects of some missing mechanism, we impose non-universal gaugino masses at the GUT scalem and explore the low scale…