相关论文: Gauge coupling unification in a minimal non-supers…
We calculate the weak scale MSSM spectrum starting from a heterotic string theory compactified on an anisotropic orbifold. Supersymmetry breaking is mediated by vector-like exotics that arise naturally in heterotic string theories. The…
In light of null results from New Physics searches at the LHC, we look at unification of the gauge couplings as a model-building principle. As a first step, we consider extensions of the Standard Model with vector-like fermions. We present…
The string landscape suggests that the supersymmetry breaking scale can be high, and then the simplest low energy effective theory is the Standard Model (SM). Considering grand unification scale supersymmetry breaking, we show that gauge…
We recapitulate the latest results on the class of the simplest SO(10) grand unified models in which the GUT-scale symmetry breaking is triggered by an adjoint Higgs representation. We argue that the minimal survival approximation…
The idea of grand unification in a minimal supersymmetric SU(5)xSU(5) framework is revisited. It is shown that the unification of gauge couplings into a unique coupling constant can be achieved at a high-energy scale compatible with proton…
We investigate unification prospects of two heavy scalar triplet extension of the standard model where, in the absence of any right-handed neutrino (RHN), type-II seesaw accounts for current oscillation data with hierarchical neutrino…
We examine the consequences of leptoquark explanation of HERA anomaly in the context of R parity conserving supersymmetric gauge unified theory with the gauge unification scale at $\sim 10^{16}$ GeV. We pointed out the difficulty of…
A model for electroweak unification of quarks and leptons, in a gauge group $SU_{C}(3)\times SU(4)\times U_{X}(1)$ is constructed. The model requires, three generations of quarks and leptons which are replicas (mirror) of the standard…
We show that contrary to first expectations realistic three generation supersymmetric intersecting brane world models give rise to phenomenologically interesting predictions about gauge coupling unification. Assuming the most economical way…
We propose a unified model for the three Standard Model (SM) gauge symmetries and $SU(3)$ family symmetry based on $SO(16)$ grand unified gauge symmetry on six-dimensional (6D) spacetime. In this model, three chiral generations of quarks…
We present a minimal renormalizable non-supersymmetric SO(10) grand unified model with a symmetry breaking sector consisting of Higgs fields in the 54_H + 126_H + 10_H representations. This model admits a single intermediate scale…
We look for minimal extensions of Standard Model with vector like fermions leading to precision unification of gauge couplings. Constraints from proton decay, Higgs stability and perturbativity are considered. The simplest models contain…
We study a non-supersymmetric SO(10) Grand Unification Theory with a very high energy intermediate symmetry breaking scale in which not only gauge but also Yukawa coupling unification are enforced via suitable threshold corrections and…
We make a detailed analysis of gauge coupling unification in supersymmetry. When the Standard Model gauge group is embedded in a Grand Unified Theory, new particles often appear below the GUT scale in order to predict the right…
In Grand Unified Theories (GUTs), the Standard Model (SM) gauge couplings need not be unified at the GUT scale due to the high-dimensional operators. Considering gravity mediated supersymmetry breaking, we study for the first time the…
A $Z'$ gauge boson with sub-GeV mass has acquired a significant interest in phenomenology, particularly in view of the muon $g-2$ anomaly and coherent elastic neutrino-nucleon scattering. The latter is challenged by the nuclear recoil…
I investigate the phenomenology of supersymmetric models with extra vector-like supermultiplets that couple to the Standard Model gauge fields and transform as the fundamental representation of a new confining non-Abelian gauge interaction.…
It is often argued that in the class of non-supersymmetric SO(10) grand unified theories there is barely any room for reconciling the lower bound on the position of the GUT scale emerging from the proton decay searches and the lower limit…
We propose a natural Higgs sector in E_6 grand unified theory (GUT) with anomalous U(1)_A gauge symmetry. In the scenario, the doublet-triplet splitting can be realized while the proton decay via dimension 5 operator is suppressed. The…
We study the proton lifetime in the $SO(10)$ Grand Unified Theory (GUT), which has the left-right (LR) symmetric gauge theory below the GUT scale. In particular, we focus on the minimal model without the bi-doublet Higgs field in the LR…