A heavy little Higgs and a light Z' under the radar
  The original littlest Higgs model with universal fermion couplings is found to be consistent with precision electroweak data but is strongly constrained by Tevatron limits on the predicted centi-weak Z' boson. A possible signal observed by CDF at 240 GeV is consistent with the predicted Z' and a region below 150 GeV is largely unconstrained by collider data. 
Michael S. Chanowitz
hep-ph hep-ex