Related papers: A Common Source for Scalars: Axiflavon-Higgs Unifi…
Gauge-Higgs unification is the fascinating scenario solving the hierarchy problem without supersymmetry. In this scenario, the Standard Model (SM) Higgs doublet is identified with extra component of the gauge field in higher dimensions and…
Exotic Higgs decays are promising channels to discover new physics in the near future. We present a simple model with a new light scalar that couples to the Standard Model through a charged lepton-flavor violating interaction. This can…
We summarize recent studies of realistic nonsupersymmetric Grand Unified Theories (GUTs) extended with a global $U(1)_{\rm PQ}$ symmetry, so as to accommodate the axion solution to the strong CP problem. Aside from solving the CP problem…
New singlet scalar bosons have broad phenomenological utility and feature prominently in many extensions of the Standard Model. Such scalars are often taken to have Higgs-like couplings to SM fermions in order to evade stringent flavor…
We argue that adding gauge-singlet real scalars to the Standard Model can both ameliorate the little hierarchy problem and provide a realistic source of Dark Matter. Masses of the scalars should be in the 1-3 TeV range, while the lowest…
We present a minimal viable Gauge-Higgs Grand Unification scenario in warped space based on a $SU(6)$ bulk symmetry - unifying the gauge symmetries of the SM and their breaking sector. We show how the issue of light exotic new states is…
We study a class of models in which the Higgs pair production is enhanced at hadron colliders by an extra neutral scalar. The scalar particle is produced by the gluon fusion via a loop of new colored particles, and decays into di-Higgs…
Little Higgs Models have been introduced to resolve the fine-tuning problems associated with the stability of the electroweak scale and the constraints imposed by the precision electroweak analysis of experiments testing the Standard Model…
We present a minimal model for particle physics and cosmology. The Standard Model (SM) particle content is extended by three right-handed SM-singlet neutrinos N_i and a vector-like quark Q, all of them being charged under a global lepton…
Discovery of neutrino mass has put the spotlight on supersymmetric SO(10) as a natural candidate for grand unification of forces and matter. However, the suppression of proton decay is a major problem in any supersymmetric grand unified…
We derive bounds on the Higgs boson coupling $g^{\prime}$ to a stable light scalar which is regarded as a collisional dark matter candidate. We study the behaviour of this scalar, that we refer to as phion ($\phi$), in the early Universe…
The apparent finding of a 125-GeV light Higgs boson closes unitarity of the minimal Standard Model (SM), that is weakly interacting: this is an exceptional feature not generally true if new physics exists beyond the mass gap found at the…
We consider the impact of colored scalars that can couple directly to matter fields on the recently measured h to gamma gamma excess. Among all possible candidates only scalar states transforming as (8, 2,1/2) and (6,3,1/3) under the…
We construct a scalar dark matter model with $U(1)_{L_\mu-L_\tau}$ symmetry in which the dark matter interacts with the quark flavours, allowing lepton non-universal $b \to s \ell \bar{\ell}$ decays. The model can solve $b \to s \mu \mu$…
Axions arise in many theoretical extensions of the Standard Model of particle physics, in particular the "string axiverse". If the axion masses, $m_a$, and (effective) decay constants, $f_a$, lie in specific ranges, then axions contribute…
In 2001, a supersymmetric model was proposed to relate the axion scale to that of neutrino mass seesaw. Whereas this scenario is realistic, the particles associated with this mechanism are either too heavy or too weakly coupled for them to…
Precision measures of electroweak and flavour observables, at both low and high energies, are highly complementary to direct searches for New Physics at high-energy colliders. Despite the discovery of the Higgs boson at the Large Hadron…
We propose a non-universal $\mathrm{U}(1)_{X}$ gauge extension to the Standard Model (SM) and an additional Peccei-Quinn (PQ) global symmetry to study the mass hierarchy and strong CP problem. The scheme allows us to distinguish among…
The neutrino mass and dark matter (DM) problems are addressed in a Standard Model extension where the type-II seesaw and scotogenic mechanisms coexist. The model features a flavour $\mathcal{Z}_8$ discrete symmetry which is broken down to a…
We show how the scales responsible for Peccei-Quinn (PQ), seesaw, and Froggatt and Nielsen (FN) mechanisms can be fixed, by constructing a compact model for resolving rather recent, but fast-growing issues in astro-particle physics,…