相关论文: High scale boundary conditions with an additional …
If the LHC does only find a Higgs boson in the low mass region and no other new physics, then one should reconsider scenarios where the Standard Model with three right-handed neutrinos is valid up to Planck scale. We assume in this spirit…
We investigate high scale boundary conditions on the quartic Higgs-couplings and their $\beta$-functions in the Type-II Two Higgs Doublet Model and the Inert Doublet Model. These conditions are associated with two possible UV physics…
We investigate Planck scale boundary conditions on the Higgs sector of the standard model with a gauge singlet scalar dark matter. We will find that vanishing self-coupling and Veltman condition at the Planck scale are realized with the 126…
Constraints on quartic interactions of the Higgs boson with gauge bosons have been obtained by the experimental LHC collaborations focussing on the so-called $\kappa$ framework of flat rescalings of SM-like interactions in weak boson fusion…
Matching conditions relate couplings to particle masses. We discuss the importance of one-loop matching conditions in Higgs and top-quark sector as well as the choice of the matching scale. We argue for matching scales $\mu_{0,t} \simeq…
We consider the conditions for the validity of a two-Higgs doublet model at high energy scales, together with all other low- and high-energy constraints. The constraints on the parameter space at low energy, including the measured value of…
We consider the Type-II seesaw model extended with another Higgs doublet, which is odd under the $Z_2$ symmetry. We look for the possibility of triggering the electroweak symmetry breaking via radiative effects. The Higgs mass parameter…
We consider dominant 3-, 4-, and 5-loop contributions to $\lambda$, the quartic scalar coupling-constant's $\beta$-function in the Standard Model. We find that these terms accelerate the evolution of $\lambda$ to nonperturbative values,…
We demonstrate that Standard Model vacuum stability exhibits extreme sensitivity to the Higgs quartic coupling: a mere 3\% enhancement represents the critical threshold separating metastability from absolute stability with UV Landau poles.…
The scalar singlet model extends the Standard Model with the addition of a new gauge singlet scalar. We re-examine the limits on the new scalar from oblique parameter fits and from a global fit to precision electroweak observables and…
In this article we examine the prospect of first order phase transition with a Y=0 real $SU(2)$ triplet extension of the Standard Model, which remains odd under $Z_2$, considering the observed Higgs boson mass, perturbative unitarity, dark…
In order to realize electroweak first order phase transition, a category of extended Higgs models with relatively large self-coupling constants is often considered. In such a scenario, the running coupling constants can blow up at an energy…
Recent excesses across different search modes of the collaborations at the LHC seem to indicate the presence of a Higgs-like scalar particle at 125 GeV. Using the current data sets, we review and update analyses addressing the extent to…
Heavy neutral leptons (HNLs) are an attractive minimal extension of the Standard Model, as is a singlet scalar $s$ mixing with the Higgs boson. If both are present, it is natural for HNLs to interact with $s$. For a light singlet,the decay…
Working in the context of the CMSSM, we argue that phenomenological constraints now require the universal soft supersymmetry-breaking scalar mass m_0 be non-zero at the input GUT scale. This conclusion is primarily imposed by the LEP lower…
We show how a heavy scalar singlet with a large vacuum expectation value can evade the potential instability of the Standard Model electroweak vacuum. The quartic interaction between the heavy scalar singlet and the Higgs doublet leads to a…
We revisit the fine-tuning problem in the Standard Model (SM) and show the modification in Veltman condition by virtue of a minimally-extended particle spectrum with one real SM gauge singlet scalar field. We demand the new scalar to…
New limits on the Higgs mass from LEP and new calculations on the radiative (penguin) decay of the b->s gamma branching ratio restrict the parameter space of the Constrained Minimal Supersymmetric Standard Model (CMSSM). We find that for…
The Higgs quartic coupling has now been indirectly measured at the electroweak scale. Assuming no new low-scale physics, its running is known and, together with gauge and Yukawa couplings, it is a crucial new piece of information…
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…