Low Q^2 Weak Mixing Angle Measurements and Rare Higgs Decays
Abstract
A weighted average weak mixing angle theta_W derived from relatively low Q^2 experiments is compared with the Standard Model prediction obtained from precision measurements. The approximate 1.8 sigma discrepancy is fit with an intermediate mass (~ 10-35 GeV) "dark" Z boson Z_d, corresponding to a U(1)_d gauge symmetry of hidden dark matter, which couples to our world via kinetic and Z-Z_d mass mixing. Constraints on such a scenario are obtained from precision electroweak bounds and searches for the rare Higgs decays H -> Z Z_d -> 4 charged leptons at the LHC. The sensitivity of future anticipated low Q^2 measurements of sin^2 theta_W(Q^2) to intermediate mass Z_d is also illustrated. This dark Z scenario can provide interesting concomitant signals in low energy parity violating measurements and rare Higgs decays at the LHC, over the next few years.
Keywords
Cite
@article{arxiv.1507.00352,
title = {Low Q^2 Weak Mixing Angle Measurements and Rare Higgs Decays},
author = {Hooman Davoudiasl and Hye-Sung Lee and William J. Marciano},
journal= {arXiv preprint arXiv:1507.00352},
year = {2015}
}
Comments
Version to appear in PRD