Related papers: Fermion Dark Matter Effect on Electroweak Phase Tr…
New fermions, strongly coupled to the Standard Model Higgs boson provide a well motivated extension of the Standard Model (SM). In this work we show that, once new physics at heavier scales is added to stabilize the Higgs potential, such an…
We consider scenarios in which dark matter is a Majorana fermion which couples to Standard Model fermions through the exchange of charged mediating particles. The matrix elements for various dark matter annihilation processes are then…
We study first-order electroweak phase transitions nonperturbatively, assuming any particles beyond the Standard Model are sufficiently heavy to be integrated out at the phase transition. Utilising high temperature dimensional reduction, we…
We reconsider the strength of the electroweak phase transition in the singlet Majoron extension of the Standard Model, with a low (~TeV) scale of the singlet VEV. A strongly first order phase transition, of interest for electroweak…
We analyse the phenomenology of a simplified model for a real scalar dark matter candidate interacting with quarks via a coloured fermionic mediator. In the coannihilation regime, the dark matter abundance is controlled by the dynamics of…
In this paper, the electroweak phase transition, the gravitational waves and the dark matter issues are investigated in two scalar singlet extension of the standard model. The detectability of the gravitational wave signals are discussed by…
We investigate the non-zero temperature dynamics of a sub-GeV dark matter scenario freezing-out via self-interactions. As a prototype, we take up the case of a scalar dark matter species undergoing $3 \to 2$ number changing annihilations…
We study an extension of the vector-like lepton dark matter model by introducing scalar leptoquarks that modify the properties of the vector-like lepton dark matter candidate, helping it evade stringent direct detection constraints. In the…
Inspired by the recent evidences of nano-Hertz stochastic gravitational waves observed by the pulsar timing array collaborations, we explore their implied supercooled electroweak phase transition in the singlet extension of the Standard…
The electroweak symmetry breaking (EWSB) sector of the Standard Model can be far richer and more interesting than the usual single scalar doublet model. We explore scenarios where the EWSB sector is nearly scale invariant and consequently…
We review a class of models in which the Standard Model (SM) is augmented by vector-like leptons: one doublet and a singlet, which are odd under an unbroken discrete $Z_2$ symmetry. As a result, the neutral component of these additional…
This closer study of the FSM: [I] retains the earlier results in offering explanation for the existence of three fermion generations, as well as the hierarchical mass and mixing patterns of leptons and quarks; [II] predicts a vector boson…
We present a detailed study of a combined singlet-doublet fermion and triplet scalar model for dark matter. These models have only been studied separately in the past. Together, they form a simple extension of the Standard Model that can…
A new type of dark matter (DM) theories are proposed in the light of the standard model (SM) singlet scalar $\phi$ which is responsible for the diphoton excess at the LHC Run 2. In the so-called $\phi$-portal DM models, after taking into…
We study the effect of BSM particles receiving most of their mass from their coupling to the Higgs boson ("Loryons") on the electroweak phase transition. The existence of BSM Loryons would imply that electroweak symmetry must be…
In these proceedings, we present a study of a combined singlet--doublet fermion and triplet scalar model for dark matter (DM). Together, these models form a simple extension of the Standard Model (SM) that can account for DM and explain the…
We investigate an one loop radiative neutrino mass model, where the loop particles, notably a singlet fermion ($\chi$), a doublet fermion ($\Psi$) and three generations of singlet scalars ($\phi_i, i=\{1,2,3\}$) are assumed to be odd under…
We perform a global fit of the extended scalar singlet model with a fermionic dark matter (DM) candidate. Using the most up-to-date results from the $\mathit{Planck}$ measured DM relic density, direct detection limits from the XENON1T…
Sterile neutrinos, fermions with no standard model couplings [SU(2) singlets], are predicted by most extensions of the standard model, and may be the dark matter. I describe the nonthermal production and linear perturbation evolution in the…
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…