Related papers: Probing the Electroweak Phase Transition in the Da…
We study phase transitions in a softly broken $U(1)$ complex singlet scalar model in which the dark matter is the pseudo-scalar part of a singlet whose direct detection coupling to matter is strongly suppressed. Our aim is to find ways to…
In this talk, I describe a class of electroweak (EW) scale dark matter (DM) models where its stability or longevity are the results of underlying dark gauge symmetries: stable due to unbroken local dark gauge symmetry or topology, or…
The stability of "visible" electroweak-type cosmic strings is investigated in an extension of the Standard Model (SM) by a minimal dark sector, consisting of a U(1) gauge field, broken spontaneously by a scalar. The "visible" and dark…
One of the simplest models of dark matter is that where a scalar singlet field S comprises some or all of the dark matter, and interacts with the standard model through an HHSS coupling to the Higgs boson. We update the present limits on…
Beyond the Standard Model physics is required to explain both dark matter and the baryon asymmetry of the universe, the latter possibly generated during a strong first-order electroweak phase transition. While many proposed models tackle…
We investigate a dark matter model involving an inert $\mathrm{SU}(2)_\mathrm{L}$ quadruplet scalar with hypercharge 1/2. After the electroweak symmetry breaking, the dark sector contains one doubly charged, two singly charged, and two…
We propose novel bosonic Technicolor models augmented by an $SU(2)_R$ gauge group and scalar doublet. Dynamical breaking of $SU(2)_R$ induced by technifermion condensation triggers $SU(2)_L$ breaking via a portal coupling. The scale of the…
We consider phase transitions in the standard model (SM) without the Higgs mass term, which is coupled through a Higgs portal term to an SM singlet, classically scale-invariant gauge sector with SM singlet scalar fields. At lower energies…
We perform a comprehensive study of a model in which the Higgs sector is extended to contain two Higgs doublet fields, with the four types of possibilities to couple to standard fermions, as well as an additional light pseudoscalar Higgs…
We investigate a two-component dark matter scenario in the type-I two-Higgs-doublet model. The dark sector contains a real scalar $s$ and a Dirac fermion $\chi$, whose stability is ensured by a $Z_4$ symmetry together with kinematic…
We study a model of spin-1 dark matter which interacts with the Standard Model predominantly via exchange of Higgs bosons. We propose an alternative UV completion to the usual Vector Dark Matter Higgs Portal, in which vector-like fermions…
A new weak-isospin triplet of scalar bosons is introduced to the Standard Model in order to ensure the electroweak symmetry for a conjectured new weak coupling between a hidden sector of the Universe, responsible for cold dark matter, and…
In an extension to the scale invariant standard model by two real singlet scalars $s$ and $s'$ in addition to the Higgs field, we investigate the strong first-order electroweak phase transition as a requirement for baryogenesis. This is the…
We propose a vector dark matter model with an exotic dark SU(2) gauge group. Two Higgs triplets are introduced to spontaneously break the symmetry. All of the dark gauge bosons become massive, and the lightest one is a viable vector DM…
The dark sector, composed of the fields neutral under the Standard Model (SM) gauge group, can couple to the SM through the Higgs, hypercharge and neutrino portals, and pull the SM towards its scale by loop corrections. This instability,…
A dark sector with non-abelian gauge symmetry provides a sound framework to justify stable dark matter (DM) candidates. We consider scalar fields charged under a $SU(N)$ gauge group, and show that the centre of $SU(N)$, the discrete…
We study a conformal version of the Standard Model (SM), which apart from SM sector, containing a $ U_{D}(1) $ dark sector with a vector dark matter candidate and a scalar field (scalon). In this model the dark sector couples to the SM…
If the Higgs boson H couples to a singlet scalar S via lambda_m |H|^2 S^2, a strong electroweak phase transition can be induced through a large potential barrier that exists already at zero temperature. In this case properties of the phase…
We explore the phenomenological consequences of a model with an extended scalar sector, incorporating strongly coupled inert Higgs doublets. The model introduces three Higgs doublets: one that interacts with the $SU(2)$ symmetry of the…
As the 125 GeV Higgs becomes disfavored as a portal to the dark sector, one is motivated to look beyond the SM-Higgs sector, into extended scalar-mediated portal mechanisms. In this work we consider one interesting possibility of such…