Electroweak interaction

About: Electroweak interaction is a research topic. Over the lifetime, 16333 publications have been published within this topic receiving 468927 citations. The topic is also known as: electroweak force.

Inflation and Dark Matter in the Higgs Portal of Classically Scale Invariant Standard Model

Abstract: We consider a minimal classically scale-invariant extension of the Standard Model. In this theory, the Higgs mechanism is triggered and the electroweak symmetry breaking is generated radiatively by the Coleman-Weinberg sector which is coupled to the SM Higgs. We extend the Higgs portal interactions of the theory to include an additional singlet which is also non-minimally coupled to gravity. This generates a single-field slow-roll inflation mechanism in the effective field theory formulation which is robust up to Planck scales. Our approach does not require integrating in any additional new physics degrees of freedom to unitarise the theory in the sub-Planckian regime where inflation happens. As a result, no large threshold corrections appear in our approach to inflation so that the electroweak scale and the SM Higgs mass are not affected. The singlet field responsible for inflation also gives a viable dark matter candidate in our model. We also discuss the relation between classical scale-invariance of the effective theory and the possible local scale invariance of the full theory and comment on the naturalness of the electroweak scale.

Constraints on the bulk standard model in the Randall-Sundrum scenario

Abstract: We derive constraints on the Randall-Sundrum scenario with the standard model fields in the bulk. These result from tree level effects associated with the deformation of the zero mode wave functions of the W and the Z once electroweak symmetry is broken. Recently Cs\'aki, Erlich and Terning pointed out that this implies large contributions to electroweak oblique parameters. Here we find that when fermions are allowed in the bulk the couplings of the W and the Z to zero-mode fermions are also affected. We perform a fit to electroweak observables, assuming universal bulk fermion masses and including all effects, and find constraints that are considerably stronger than for the case with fermions localized in the low energy boundary. These put the lowest Kaluza-Klein excitation out of reach of the CERN Large Hadron Collider. We then relax the universality assumption and study the effects of flavor violation in the bulk and its possible signatures.

Grand unified theory with heavy color

Abstract: An example of the unification of electroweak, color, and heavy-color forces in the unifying group SU(7) is presented. This simple toy model predicts a nontrivial mass spectrum for two families of quarks and leptons. The usual Higgs scalar sector is replaced by the strong interaction heavy-color sector at \ensuremath{\sim} 1 TeV.

Next-to-minimal supersymmetric model solution to the fine-tuning problem, precision electroweak constraints, and the largest CERN LEP Higgs event excess

Abstract: We present an extended study of how the next-to-minimal supersymmetric model easily avoids fine-tuning in electroweak symmetry breaking for a SM-like light Higgs with mass in the vicinity of 100 GeV, as beautifully consistent with precision electroweak data, while escaping LEP constraints due to the dominance of h{yields}aa decays with m{sub a} 30 GeV, and decays primarily to {gamma}{gamma} leading to an h{yields}aa{yields}4{gamma} Higgs signal.

Excluding electroweak baryogenesis in the MSSM

Abstract: In the context of the MSSM the Light Stop Scenario (LSS) is the only region of parameter space that allows for successful Electroweak Baryogenesis (EWBG). This possibility is very phenomenologically attractive, since it allows for the direct production of light stops and could be tested at the LHC. The ATLAS and CMS experiments have recently supplied tantalizing hints for a Higgs boson with a mass of ≈ 125 GeV. This Higgs mass severely restricts the parameter space of the LSS, and we discuss the specific predictions made for EWBG in the MSSM. Combining data from all the available ATLAS and CMS Higgs searches reveals a tension with the predictions of EWBG even at this early stage. This allows us to exclude EWBG in the MSSM at greater than (90) 98% confidence level in the (non-)decoupling limit, by examining correlations between different Higgs decay channels. We also examine the exclusion without the assumption of a ≈ 125 GeV Higgs. The Higgs searches are still highly constraining, excluding the entire EWBG parameter space at greater than 90% CL except for a small window of m h ≈ 117-119 GeV.