  New physics models admit the interesting possibility of a Z' weak boson
associated with an extra U(1) gauge symmetry and a Higgs boson that is heavy
enough to decay into a pair of Z bosons. Then Z' production and decay via Z' ->
ZH -> ZZZ has a distinctive LHC signal that is nearly background free and
reconstructs the H and Z' masses and widths. The Z' decay to 3 pairs of leptons
is especially distinctive. The ZH decay mode exists even if the Z' is decoupled
from leptons, which motivates an independent 6-lepton resonance search
regardless of the dilepton search results.

High Energy Physics - Phenomenology