Related papers: From Dirac neutrino masses to baryonic and dark ma…
We consider an SU(3)'_c\times SU(2)'_L\times U(1)'_Y mirror sector where the field content and dimensionless couplings are a copy of the SU(3)_c\times SU(2)_L\times U(1)_Y ordinary sector. Our model also contains three gauge-singlet…
The $SU(3)_c^{}\times SU(2)_L^{} \times U(1)_Y^{}$ standard model is extended by a $U(1)_{B-L}^{}$ gauge symmetry with four right-handed neutrinos. Because of their Yukawa couplings to a Higgs singlet for spontaneously breaking the…
We propose a minimal model for the cosmic coincidence problem $\Omega_{\rm DM}/\Omega_B \sim 5$ and neutrino mass in a type-II seesaw scenario. We extend the standard model of particle physics with a $\rm SU(2)$ singlet leptonic Dirac…
We extend the visible content of the standard model (SM) with a hidden sector composed of three right-handed singlet neutrinos and one singlet Higgs. These extra singlets are charged under a new U(1)_X gauge symmetry while the SM particles…
We consider the minimal supersymmetric extension of the Standard Model allowing both Dirac and Majorana gauginos. The Dirac masses are obtained by pairing up extra chiral multiplets: a singlet S for U(1)_Y, a triplet T for SU(2) and an…
A dark sector resembling the standard model, where the abundance of matter is explained by baryon and lepton asymmetries, and stable constituents bind to form atoms, is a theoretically appealing possibility. We show that a minimal model…
We investigate a model of dark sector based on non-Abelian $SU(2)_D$ gauge symmetry. This dark gauge symmetry is broken into discrete $Z_2$ via vacuum expectation values of two real triplet scalars, and an $SU(2)_D$ doublet Dirac fermion…
All pieces of concrete evidence for phenomena outside the standard model (SM) - neutrino masses and dark matter - are consistent with the existence of new degrees of freedom that interact very weakly, if at all, with those in the SM. We…
We consider a simple model of a dark sector with a chiral $U(1)$ gauge symmetry. The anomaly-free condition requires at least five chiral fermions. Some of the fermions acquire masses through a vacuum expectation value of a Higgs field, and…
We study neutrino mass generation and dark matter in a left-right symmetric model. The model is based on an $SU(3)_c\times SU(2)_L \times SU(2)_R \times U(1)_{B-L}$ gauge theory with a softly broken parity symmetry. Masses of the charged…
We propose an extension of the standard model (SM) by including a dark sector comprising of three generations of heavy right-handed neutrinos, a singlet scalar and a singlet Dirac fermion, where the latter two particles are stable and are…
A Dirac fermion carrying an integral weak isospin and the vanishing hypercharge is considered as its neutral component can be a promising dark matter candidate (called the minimal dark matter) whose mass is of order 100 GeV. While the…
We propose a gauged $B-L$ extension of the standard model (SM) where light neutrinos are of Dirac type by virtue of tiny Yukawa couplings with the SM Higgs. To achieve leptogenesis, we include additional heavy Majorana fermions without…
I suggest a new extension of the standard model of particle physics, which introduces a dark sector with the $SU(2)_{D}\otimes U(1)_{D'}$ symmetry besides the SM sector. The new particles of the model all inhabit in the dark sector. The…
Dark matter is postulated to be a neutral Dirac fermion, charged under a dark $U(1)_D$ gauge symmetry. Scalar partners of the quarks and leptons are also charged under $U(1)_D$. The dark gauge boson $Z_D$ and the dark Higgs boson $h_D$…
In the type-II seesaw mechanism, the neutrino mass generation could be tested experimentally if the Higgs triplet is at the TeV scale and has a small cubic coupling to the standard model Higgs doublet. We show such small triplet-doublet…
A TeV-scale Higgs doublet with a small mixing to the standard model Higgs doublet can have the sizable Yukawa couplings to several right-handed neutrinos and the standard model lepton doublets. This provides a testable Dirac neutrino mass…
We propose a novel cogenesis mechanism by utilising the two-body decay of heavy vector-like fermions to dark matter (DM) $\chi$ and right chiral part of light Dirac neutrino $\nu_R$ via the electromagnetic dipole operator. This leads to…
We study a $U(1)_{B-L}$ extension of the Standard Model (SM) in which Dirac neutrino masses are generated radiatively at the one-loop level through the exchange of new beyond the SM fields. This framework establishes a direct connection…
Lepton number is promoted to an $U(1)_L$ gauge symmetry in a simple extension of the standard model. The spontaneous breaking of $U(1)_L$ by three units allows a conserved $Z_3^L$ lepton symmetry to remain, guaranteeing that neutrinos are…