Related papers: Singlet Portal to the Hidden Sector
The LHC has strongly constrained models of supersymmetry with traditional missing energy signatures. We present a variety of models that realize the concept of Stealth Supersymmetry, i.e. models with R-parity in which one or more…
The simplest extension of the Two Higgs Doublet Model is the addition of a real scalar singlet, S. The effects of mixing between the singlet and the doublets can be manifested in two ways. It can modify the couplings of the 126 GeV Higgs…
By extending the scalar sector of the Standard Model (SM) by a U(1) singlet, we show that the electroweak symmetry breaking enables the formation of a stable, electrically neutral, colorless Q-ball which couples to the SM particle spectrum…
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…
After the discovery of the 125 GeV Higgs boson, the Next-to-Minimal Supersymmetric Standard Model (NMSSM) has become more interesting as a model for new physics since new tree-level contributions to the Higgs mass makes it easier to…
Kinetic mixing of the dark photon, the gauge boson of a hidden $U(1)_D$, with the Standard Model (SM) gauge fields to induce an interaction between ordinary matter and dark matter (DM) at 1-loop requires the existence of portal matter (PM)…
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…
The asymmetric Higgs sector of one $SU(2)_L \times SU(2)_R$ bidoublet $(\phi_1^0,\phi_1^-;\phi_2^+,\phi_2^0)$ and one $SU(2)_R$ doublet [but no $SU(2)_L$ doublet] is considered in a nonsupersymmetric left-right extension of the standard…
The vector portal/kinetic mixing simplified model of dark matter, in which thermal dark matter of a mass ranging from a few MeV to a few GeV can be realized with a dark-sector $U(1)$, relies on a small kinetic mixing term between this dark…
The Higgs boson spectrum of the Next-to-Minimal Supersymmetric Standard Model is examined. The model includes a singlet Higgs field S in addition to the two Higgs doublets of the minimal extension. `Natural' values of the parameters of the…
We examine the implications of singlet-doublet Higgs mixing on the properties of a Standard Model (SM)-like Higgs boson within the Peccei-Quinn invariant extension of the NMSSM (PQ-NMSSM). The SM singlet added to the Higgs sector connects…
Several models of dark matter motivate the concept of hidden sectors consisting of SU(3)_C x SU(2)_L x U(1)_Y singlet fields. The interaction between our and hidden matter could be transmitted by new abelian U'(1) gauge bosons A' mixing…
We consider a conformal complex singlet extension of the Standard Model with a Higgs portal interaction. The global $U(1)$ symmetry of the complex singlet can be either broken or unbroken and we study each scenario. In the unbroken case,…
We consider a hidden sector dark matter, where a singlet fermion is a cold dark matter and a real singlet scalar boson $S$ is a messenger between the SM and the hidden sectors. This singlet scalar will mix with the SM Higgs boson $h$, and…
Inspired by the concept of complementarity, we present a illustrative model for the weak interactions with unbroken gauge symmetry and unbroken supersymmetry. The observable particles are bound states of some more fundamental particles.…
We consider a hidden sector model of dark matter which is charged under a hidden U(1)_X gauge symmetry. Kinetic mixing of U(1)_X with the Standard Model hypercharge U(1)_Y is allowed to provide communication between the hidden sector and…
We investigate the impact of interactions between hidden sectors and the discovered Higgs boson $h_{125}$, allowing for additional invisible decay channels of $h_{125}$. We perform $\chi^2$-fits to the measurements of the Higgs-boson cross…
In the Next-to Minimal Supersymmetric Standard Model (NMSSM), a sizable coupling $\lambda$ between the singlet and Higgs fields can naturally accommodate the observed Higgs boson mass of 125 GeV. This large coupling also results in a large…
We study scalar singlet extensions of the Standard Model (SM), focusing on scenarios where dark matter (DM) is stabilized by a \(\mathbb{Z}_2\) symmetry. In the minimal single-scalar extension of the SM, only a narrow region near the Higgs…
The significance of the electroweak phase transition is undeniable, and although initially it was believed that it was second-order, it is now believed that it is a first-order transition. However, it is not a strong first-order phase…