The muon anomalous magnetic moment in the Randall-Sundrum model

We study the lepton sector of composite Higgs models with partial compositeness. The standard anarchic scenario is in conflict with the absence of observable charged lepton flavor violation. This tension can be completely solved in MFV scenarios that require either left-handed or right-handed SM leptons to be equally composite. Constraints on this scenario are weak and the composite lepton partners could be as light as few hundreds GeVs with interesting LHC signatures. The contribution to the muon (g − 2) in theories where the Higgs is a pseudo Nambu-Goldstone boson is also discussed.

Section: Muon G −supporting

confidence: 80%

Leptons in composite MFV

Redi

2013

“…This fact has also been realized in [45]. The situation resembles that encountered when one compares the original RS model, in which only gravity was allowed to propagate in the extra dimension while all SM fields were confined to the IR brane [3], with the more popular models in which all matter and gauge fields live in the bulk [6].…”

Section: Jhep01(2014)173mentioning

confidence: 65%

5D perspective on Higgs production at the boundary of a warped extra dimension

Malm

Neubert

Novotny

et al. 2014

108

A comprehensive, five-dimensional calculation of Higgs-boson production in gluon fusion is performed for both the minimal and the custodially protected RandallSundrum (RS) model, with Standard Model fields propagating in the bulk and the scalar sector confined on or near the IR brane. For the first time, an exact expression for the gg → h amplitude in terms of the five-dimensional fermion propagator is derived, which includes the full dependence on the Higgs-boson mass. Various results in the literature are reconciled and shown to correspond to different incarnations of the RS model, in which the Higgs field is either localized on the IR brane or is described in terms of a narrow bulk state. The results in the two scenarios differ in a qualitative way: the gg → h amplitude is suppressed in models where the scalar sector is localized on the IR brane, while it tends to be enhanced in bulk Higgs models. In both cases, effects of higher-dimensional operators contributing to the gg → h amplitude at tree level are shown to be numerically suppressed under reasonable assumptions. There is no smooth cross-over between the two scenarios, since the effective field-theory description breaks down in the transition region. A detailed phenomenological analysis of Higgs production in various RS scenarios is presented, and for each scenario the regions of parameter space already excluded by LHC data are derived.

“…These are generated via lepton flavor conserving penguin diagrams and have recently been computed for warped models in ref. [41]. Given that the EW KK contributions are somewhere close to the observed deviation and that leptonic gauge couplings can be close to the weak ones, it would be interesting to perform a detailed study.…”

Section: Jhep02(2013)079mentioning

confidence: 87%

Neutrino mixing from Wilson lines in warped space

Gersdorff

Quirós

Wiechers

2013

Abstract:We consider the generation of the hierarchical charged lepton spectrum and anarchic neutrino masses and mixing angles in warped extra dimensional models with Randall-Sundrum metric. We have classified all possible cases giving rise to realistic spectra for both Dirac and Majorana neutrinos. An anarchic neutrino spectrum requires a convenient bulk symmetry broken by boundary conditions on both UV and IR branes. We have in particular considered the case of Majorana neutrinos with a continuous bulk symmetry. To avoid unwanted massless extra gauge bosons the 4D group should be empty. If the 4D coset is not vanishing it can provide a Wilson Line description of the neutrino Majorana mass matrix. We have studied an example based on the bulk gauge group U(3) ℓ ⊗ U(3) N ⊗ i U(1) E i with the Wilson Line in SO(3) N satisfying all required conditions. A χ 2 -fit to experimental data exhibits 95% CL region in the parameter space with no finetuning. As a consequence of the symmetries of the theory there is no tree-level induced lepton flavor violation and so one-loop processes are consistent with experimental data for KK-modes about a few TeV. The model is easily generalizable to models with IR deformed metrics with similar conclusions.