Precision Electroweak Observables in the Minimal Moose Little Higgs Model

Abstract

Little Higgs theories, in which the Higgs particle is realized as the pseudo-Goldstone boson of an approximate global chiral symmetry have generated much interest as possible alternatives to weak scale supersymmetry. In this paper we analyze precision electroweak observables in the Minimal Moose model and find that in order to be consistent with current experimental bounds, the gauge structure of this theory needs to be modified. We then look for viable regions of parameter space in the modified theory by calculating the various contributions to the S and T parameters.

Little composite dark matter

“…One realization of the composite Higgs scenario is the Littlest Higgs [10][11][12][13][14][15][16]. The original model is strongly constrained by electroweak precision tests (EWPT) due to tree level contributions to electroweak observables [17][18][19][20][21][22][23][24]. These constraints required the symmetry breaking scale f to be a few TeV, thus reintroducing considerable fine-tuning.…”

Little-Higgs corrections to precision data after CERN LEP2

“…We here stick to the simplest choice made in the original literature, although introducing more 'epycicles' gives interesting alternatives [13]. 2 We improve on previous computations and analyses [17,18,19,20,21,22,23] in the following ways. Most little-Higgs models are 'universal': all effects can be encoded in four parameters, S,T , W, Y .…”

Collective Quartics from Simple Groups

“…In fact, many models with top partners can have large positive contributions to the T parameter (see for instance [18,34,35]) and this negative contribution might be desirable. Further problems with electroweak precision tests, most importantly the S parameter, are alleviated by the minimal structure of the model [36][37][38]. The relevant measurements for collider physics depend upon the origin of the top quark's Yukawa coupling.…”