  We construct a little Higgs model with the most minimal extension of the
standard model gauge group by an extra U(1) gauge symmetry. For specific charge
assignments of scalars, an approximate U(3) global symmetry appears in the
cutoff-squared scalar mass terms generated from gauge bosons at one-loop level.
Hence, the Higgs boson, identified as a pseudo-Goldstone boson of the broken
global symmetry, has its mass radiatively protected up to scales of 5-10 TeV.
In this model, a Z2 symmetry, ensuring the two U(1) gauge groups to be
identical, also makes the extra massive neutral gauge boson stable and a viable
dark matter candidate with a promising prospect of direct detection.

High Energy Physics - Phenomenology;Astrophysics