Related papers: Electroweak Baryogenesis with Anomalous Higgs Coup…
The realisation that the electroweak anomaly can induce significant baryon number violation at high temperature and that the standard models of particle physics and cosmology contain all the ingredients needed for baryogenesis has led to…
In collaboration with G.D. Moore, the electroweak phase transition in the minimal supersymmetric standard model is studied using the two-loop effective potential. We make a comprehensive search of the MSSM parameter space consistent with…
Electroweak baryogenesis provides a very attractive scenario to explain the origin of the baryon asymmetry. The mechanism of electroweak baryogenesis makes use of the baryon number anomaly and relies on physics that can be tested…
The electroweak phase transition in the magnetic and hypermagnetic fields is studied in the Standard Model on the base of investigation of symmetry behaviour within the consistent effective potential of the scalar and magnetic fields at…
Sphaleron is a non-perturbative solution of electroweak gauge theories, which is crucially important for the scenario of electroweak baryogenesis. The sphaleron energy depends on details of the mechanism for the electroweak symmetry…
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…
We update the phenomenology of gauge singlet extensions of the Standard Model scalar sector and their implications for the electroweak phase transition. Considering the introduction of one real scalar singlet to the scalar potential, we…
Introducing heavy particles with strong couplings to the Higgs field can strengthen electroweak phase transition, through the entropy release mechanism from both bosons and fermions. We analyze the possibility of electroweak baryogenesis in…
We propose a variant of electroweak-scale baryogenesis characterized by the spontaneous breaking of the charge-parity (CP) symmetry in the early Universe driven by the vacuum expectation value of a CP-odd scalar. This CP breaking period in…
Electroweak baryogenesis in a two-Higgs doublet model is a well-motivated and testable scenario for physics beyond the Standard Model. An attractive way of providing $CP$ violation is through flavor-changing Higgs couplings, where the…
We combine the NNLO QCD description of Higgs boson production in association with an electroweak vector boson $V = W~{\rm or}~Z$ with a similarly-precise description of Higgs boson decays into a pair of massive $b$ quarks and with the…
The Higgs potential of the standard model with an additional real Higgs singlet is studied in order to examine if it may allow the strongly first order electroweak phase transition. It is found that there are parameter values for which this…
We study the viability of electroweak baryogenesis in a two Higgs doublet model scenario augmented by vector-like, electroweakly interacting fermions. Considering a limited, but illustrative region of the model parameter space, we obtain…
We discuss an extension of the standard model by fields not charged under standard model gauge symmetry in which the electroweak symmetry breaking is driven by the Higgs quartic coupling itself without the need for a negative mass term in…
We investigate the production of (longitudinal) $Z$-boson pairs in gluon fusion as a probe of anomalous Higgs couplings. Of particular interest is the kinematic region of large center-of-mass energy, where the Higgs-boson is highly…
We study the generation of the baryon asymmetry in a variant of the standard model, where the Higgs field is stabilized by a dimension-six interaction. Analyzing the one-loop potential, we find a strong first order electroweak phase…
A cosmological first order electroweak phase transition could explain the origin of the matter-antimatter asymmetry in the Universe. Such a phase transition does not occur in the Standard Model, while it becomes possible with the existence…
We discuss the possibility of breaking the electroweak symmetry in theories with extra dimensions via boundary conditions, without a physical Higgs scalar in the spectrum. In these models the unitarity violation scale can be delayed via the…
We consider the effect of the presence of a hypermagnetic field at the electroweak phase transition. Screening of the Z-component inside a bubble of the broken phase delays the phase transition and makes it stronger first order. We show…
In this thesis, our main focus is on the $HHH$ and $VVHH$ couplings which are loosely bound. The $HHH$ coupling will determine the shape the Higgs potential and $VVHH$ couplings will tell us how the gauge bosons are coupled to the Higgs…