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.

Strong Higgs interactions at a linear collider

Abstract: We study the impact of Higgs precision measurements at a high-energy and high-luminosity linear electron positron collider, such as CLIC or the ILC, on the parameter space of a strongly interacting Higgs boson. Some combination of anomalous couplings are already tightly constrained by current fits to electroweak observables. However, even small deviations in the cross sections of single and double Higgs production, or the mere detection of a triple Higgs final state, can help establish whether it is a composite state and whether or not it emerges as a pseudo-Nambu-Goldstone boson from an underlying broken symmetry. We obtain an estimate of the ILC and CLIC sensitivities on the anomalous Higgs couplings from a study of W W scattering and h h production which can be translated into a sensitivity on the compositeness scale 4 pi f, or equivalently on the degree of compositeness xi = v(2)/f(2). We summarize the current experimental constraints, from electroweak data and direct resonance searches, and the expected reach of the LHC and CLIC on xi and on the scale of the new resonances.

See-saw composite Higgs model at the LHC: Linking naturalness to the 750 GeV diphoton resonance

Abstract: We explore the possibility of explaining the recent ∼750 GeV excesses observed by ATLAS and CMS in the γγ spectrum in the context of a compelling theory of naturalness. The potential spin-zero resonance responsible for the excesses also requires the existence of new heavy charged states. We show that both such features are naturally realized in a see-saw composite Higgs model for electroweak symmetry breaking, where the new pseudo-Goldstone bosons are expected to be comparatively heavier than the Standard Model Higgs, and the new fermions have masses in the TeV range. If confirmed, the existence of this new resonance could be the first stone in the construction of a new theory of naturalness.

Electroweak Breaking on a Soft Wall

Abstract: We extend the 5D gauge-higgs scenario to the soft-wall framework where the IR brane is replaced by a smoothly decaying warp factor. The electroweak symmetry of the Standard Model is embedded in a larger symmetry group whose gauge bosons propagate in the bulk of a warped fifth dimension. This gauge symmetry is partly broken by UV boundary conditions and by a condensate of a bulk scalar field. The Higgs boson lives partly in the 5th component of the gauge field, and partly in the the bulk scalar. The Higgs potential is not UV sensitive if the condensate vanishes fast enough in the UV region. The soft-wall realization opens new possibilities for the spectrum and the couplings of the Kaluza-Klein resonances. We study two particular soft-wall backgrounds: one with resonances whose masses follow the linear Regge trajectory, and another with a continuum above a mass gap. We find that constraints on the Kaluza-Klein scale from electroweak precision tests are less severe than in analogous models with the IR brane. For the linear spectrum the typical constraint on the lightest resonance mass is 2 TeV, while the continuum is allowed to start below 1 TeV.

Large Two-Loop Contributions to g-2 from a Generic Pseudoscalar Boson

Abstract: We calculate the dominant contributions to the muon g - 2 at the two-loop level due to a pseudoscalar boson that may exist in any exotic Higgs sector in most extensions of the standard model. The leading effect comes from diagrams of the Barr-Zee type. A sufficiently light pseudoscalar Higgs boson can give rise to contribution as large as the electroweak contribution which is measurable in the next round of g - 2 experiment. The coming improved data on muon g - 2 can put the best limit on the possible existence of a light pseudoscalar boson in physics beyond the standard model.