Related papers: Light Dark Sectors through the Fermion Portal
The mirror twin Higgs framework allows for a natural Higgs mass while being consistent with collider bounds on colored symmetry partners to standard model quarks. This mechanism relies crucially on a discrete symmetry which relates each…
We study the effective field theory obtained by extending the Standard Model field content with two singlets: a 750 GeV (pseudo-)scalar and a stable fermion. Accounting for collider productions initiated by both gluon and photon fusion, we…
We consider the Singlet Majorana fermion dark matter model, in which the standard model particles interact with the dark sector through the mixing of a singlet scalar and the Higgs boson. In this model both the dark matter and the singlet…
Direct detection of and LHC search for the singlet fermion dark matter (SFDM) model with Higgs portal interaction are considered in a renormalizable model where the full Standard Model (SM) gauge symmetry is imposed by introducing a singlet…
We study an effective field theory which includes the Standard Model extended by a Dark Sector consisting of two fermionic $SU(2)_{L}$-doublets. A $Z_2$ parity guarantees that, after electroweak symmetry breaking, the lightest neutral…
The increasingly stringent bounds on the Higgs-portal coupling, arising from dark matter (DM) direct-detection searches, confront the minimal renormalizable complex scalar DM scenario with thermal production, where freeze-out occurs in the…
Models endowed with Higgs portals can probe into the hidden sectors of particle physics while providing stable dark matter candidates. Previous tree-level computations in such scenarios have shown that experimental bounds constrain dark…
The gauge-invariant operators up to dimension six in the low-energy effective field theory below the electroweak scale are classified. There are 70 Hermitian dimension-five and 3631 Hermitian dimension-six operators that conserve baryon and…
We consider an extension of the Standard Model with a singlet sector consisting of a real (pseudo)scalar and a Dirac fermion coupled with the Standard Model only via the scalar portal. We assume that the portal coupling is weak enough for…
Extensions of the Standard Model are often highly constrained by cosmology. The presence of new states can dramatically alter observed properties of the universe by the presence of additional matter or entropy. In particular, attempts too…
We introduce a dark neutrino sector which respects a hidden $U(1)^\prime$ gauge symmetry, subsequently broken by the vacuum expectation value of a dark scalar. The model is a self-consistent realisation of an extended hidden sector that…
We consider Majorana dark matter annihilation to fermion - anti-fermion pair and a photon in the effective field theory paradigm, by introducing dimension 6 and dimension 8 operators in the Lagrangian. For a given value of the cut-off…
Fermion dark matter (DM) interacting with the standard model through a Higgs portal requires non-renormalizable operators, signaling the presence of new mediator states at the electroweak scale. Collider signatures that involve the…
We study a fermionic dark matter model in which the interaction of the dark and visible sectors is mediated by Higgs portal type couplings. Specifically, we consider the mixing of a dark sector scalar with the scalars of a Two Higgs Doublet…
Fermionic dark matter interacting with the Standard Model sector through a pseudoscalar portal could evade the direct detection constraints while preserving a WIMP miracle. We study the LHC constraints on the pseudoscalar production in…
We study a gauge-singlet vector-like fermion hidden-sector dark matter model, in which the communication between the dark matter and the visible standard model sector is via the Higgs-portal scalar-Higgs mixing, and also via a hidden-sector…
An extension of the Standard Model with a hidden sector which consists of gauge singlets (a Dirac fermion $\chi$ and a scalar $S$) plus a vector boson $V_\mu$ (dark massive photon) is studied. The singlet scalar interacts with the Standard…
In this paper, we study the feeble sterile neutrino portal dark matter under the $Z_3$ symmetry. The dark sector consists of one fermion singlet $\chi$ and one scalar singlet $\chi$, which transforms as $\chi\to e^{i2\pi/3}\chi, \phi\to…
The existence of right-handed neutrinos, or heavy neutral leptons (HNLs), is strongly motivated by the observation of neutrino masses and mixing. The mass of these new particles could lie below the electroweak scale, making them accessible…
We consider a fermionic dark matter candidate interacting via a scalar mediator coupled with the Standard Model through a Higgs portal. We consider general setting including both scalar and pseudoscalar interactions between the scalar and…