Related papers: Extra U(1), effective operators, anomalies and dar…
The evidence of Dark Matter (DM) is one of the strongest observational arguments in favour of physics beyond the Standard Model. Despite expectations, a similar evidence has been lacking so far in collider searches, with the possible…
We augment the hidden Stueckelberg $Z'$ model by a pair of Dirac fermions in the hidden sector, in which the $Z'$ has a coupling strength comparable to weak scale coupling. We show that this hidden fermion-antifermion pair could be a…
We study the phenomenological credibility of a vectorial dark matter, coupled to a $Z'$ portal through Chern-Simons interaction. We scrutinize two possibilities of connecting a $Z'$ with the Standard Model: (1) through kinetic mixing and…
We explore a Standard Model extension based on a local $U(1)_B$ symmetry, where a baryon-charged scalar mediates interactions between a fermionic dark matter candidate and Standard Model quarks. In this setup, the dark matter relic…
We revisit a two-component dark matter model in which the dark matter particles are a singlet fermion ($\psi$) and a singlet scalar ($S$), both stabilized by a single $Z_4$ symmetry. The model, which was proposed by Y. Cai and A. Spray, is…
A comprehensive analysis of cosmological and collider constraints is presented for three simplified models characterised by a dark matter candidate (real scalar, Majorana fermion and real vector) and a coloured mediator (fermion, scalar and…
The quest for new physics beyond the Standard Model is boosted by the recently observed deviation in the anomalous magnetic moments of muon and electron from their respective theoretical prediction. In the present work, we have proposed a…
In this paper, we summarize phenomenology in lepton portal dark matter (DM) models, where DM couples to leptons and extra leptons/sleptons. There are several possible setups: complex/real scalar DM and Dirac/Majorana fermion DM. In…
We consider models where a massive spin-two resonance acts as the mediator between Dark Matter (DM) and the SM particles through the energy-momentum tensor. We examine the effective theory for fermion, vector and scalar DM generated in…
We show that a scalar and a fermion charged under a global U(1) symmetry can not only explain the existence and abundance of dark matter (DM) and dark radiation (DR), but also imbue DM with improved scattering properties at galactic scales,…
For understanding the hierarchies of fermion masses and mixing, we extend the Standard Model gauge group with \( U(1)_X \) and \( Z_2 \) symmetry. The field content of the Standard Model is augmented by three heavy right-handed neutrinos,…
We consider a non-exotic gauged U(1)$_X$ extension of the Standard Model (SM), where the U(1)$_X$ charge of a SM field is given by a linear combination of its hypercharge and Baryon-minus-Lepton ($B-L$) number. All the gauge and mixed…
We analyse the constraints on models of WIMP Dark Matter that can be derived from upper bounds on the "monojet" cross section at the LHC. These constraints were originally interpreted in the context of an effective field theory (EFT) where…
Combining neutrino mass generation and a dark matter candidate in a unified model has always been intriguing. We revisit the class of R$\nu$MDM models, which incorporate minimal dark matter in radiative neutrino mass models based on the…
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…
Models in which dark matter particles communicate with the visible sector through a pseudoscalar mediator are well-motivated both from a theoretical and from a phenomenological standpoint. With direct detection bounds being typically…
Dark matter (DM) without a matter asymmetry is studied in the context of Twin Higgs (TH) theories in which the LHC naturalness problem is addressed. These possess a twin sector related to the Standard Model (SM) by a (broken) $\mathbb{Z}_2$…
An extra $SU(2)_D$ gauge factor is added to the well-known left-right extension of the standard model (SM) of quarks and leptons. Under $SU(2)_L \times SU(2)_R \times SU(2)_D$, two fermion bidoublets $(2,1,2)$ and $(1,2,2)$ are assumed. The…
The hidden Stueckelberg Z' model is augmented by a pair of Dirac fermions. If the Z' has a coupling strength comparable to weak scale coupling, one can show that this hidden fermion-antifermion pair could be a milli-charged dark matter…
Many dark matter models involving weakly interacting massive particles (WIMPs) feature new, relatively light pseudoscalars that mediate dark matter pair annihilation into Standard Model fermions. In particular, simple models of this type…