Related papers: Doublet-singlet model and unitarity
The Inert Doublet Model is one of the simplest extensions of the Standard Model, providing a dark matter candidate. It is a two Higgs doublet model with a discrete $Z_2$ symmetry, that prevents the scalars of the second doublet (inert…
We investigate fermionic dark matter interactions with standard model particles from an additional $\mathrm{U}(1)_\mathrm{X}$ gauge symmetry, assuming kinetic mixing between the $\mathrm{U}(1)_\mathrm{X}$ and $\mathrm{U}(1)_\mathrm{Y}$…
We search for an extension of the Standard Model that contains a viable dark matter candidate and that can be embedded into a fundamental, asymptotically safe, quantum field theory with quantum gravity. Demanding asymptotic safety leads to…
In the two Higgs doublet model, natural flavour conservation can be achieved through the use of a discrete Z2 symmetry. A less restrictive condition is the requirement of alignment in the Yukawa sector. So far, alignment has been an anzatz,…
Recent progress on muon $g-2$ measurement prompts one to take it even more seriously. In the general two Higgs doublet model that allows extra Yukawa couplings, we take a simplified approach of single enhanced coupling. We fix the charged…
Adding a second scalar doublet (eta^+,eta^0) and three neutral singlet fermions N_{1,2,3} to the Standard Model of particle interactions with a new Z_2 symmetry, it has been shown that Re(eta^0) or Im(eta^0) is a good dark-matter candidate…
The new observation of CDMS II favors low mass WIMPs. Taking the CDMS II new results as inputs, we consider a SM singlet: the darkon as the dark matter candidate, which can be either scalar, fermion or vector. It is found that the simplest…
We consider theories with a large number $N_F$ of charged fermions and compute the renormalisation group equations for the gauge, Yukawa and quartic couplings resummed at leading order in $1/N_F$. We construct extensions of the Standard…
We discuss singlet fermion dark matter within a left-right symmetric model promoting baryon and lepton numbers as separate gauge symmetries. We add a simple Dirac fermionic dark matter singlet under $SU(2)_{L,R}$ with nonzero and equal…
Supersymmetric SO(10) Grand Unified Theories with Yukawa unification represent an appealing possibility for physics beyond the Standard Model. However Yukawa unification is made difficult by large threshold corrections to the bottom mass.…
We propose a minimal extension of the Standard Model to accommodate two-component dark matter (DM) and light neutrino mass. The symmetry of the Standard Model is enhanced by an unbroken $\mathbb{Z}_2 \times \mathbb{Z}'_2$ such that being…
For raising the radiative Higgs mass without a serious fine-tuning in the Higgs sector, we introduce vector-like lepton doublets and neutral singlets {L,L^c; N,N^c}, and consider their order one Yukawa coupling to the Higgs, W \supset…
We study a three Higgs doublet model where one doublet is inert and the other two doublets are active. Flavor changing neutral currents are avoided at tree-level by imposing a softly broken $Z'_2$ symmetry and we consider type I and type II…
We study how general two Higgs doublet models can be constrained by considering their properties under renormalization group evolution of the Yukawa couplings. We take into account both the appearance of a Landau pole as well as…
The effect of $Z_3$ symmetry on the general Two Higgs Doublet Model is explored. Of particular interest is the question of what can a $Z_3$ symmetry do beyond the usual case with $Z_2$. There are two independent scenarios that give some…
Extensions of the MSSM generically feature gauge singlet Higgs bosons. These singlet Higgs bosons have tan(beta)-enhanced Yukawa couplings to down-type quarks and leptons at the one-loop level. We present an effective Lagrangian…
Assuming that mass scales arise in nature only via dimensional transmutation, we extend the dimension-less Standard Model by adding vector-like fermions charged under a new strong gauge interaction. Their non-perturbative dynamics generates…
We consider the fermion spectrum in the strong coupling vortex phase of a lattice fermion-scalar model with a global $U(1)_L\times U(1)_R$, in 2D, in the context of a recently proposed two-cutoff lattice formulation. The fermion doublers…
Unification of electromagnetic, weak, and strong coupling constants is studied in the extension of standard model with additional fermions and scalars. It is remarkable that this unification in the supersymmetric extension of standard model…
One of the simplest viable models for dark matter is an additional neutral scalar, stabilised by a $\mathbb{Z}_2$ symmetry. Using the GAMBIT package and combining results from four independent samplers, we present Bayesian and frequentist…