The Higgs boson decay into ZZ decaying to identical fermion pairs

In order to investigate various decay channels of the Higgs boson [Formula: see text] or the hypothetical dilaton, we consider a neutral particle [Formula: see text] with zero spin and arbitrary [Formula: see text] parity. This particle can decay into two off-mass-shell [Formula: see text] bosons ([Formula: see text] and [Formula: see text]) decaying to identical fermion–antifermion pairs ([Formula: see text]): [Formula: see text]. We derive analytical formulas for the fully differential width of this decay and for the fully differential width of [Formula: see text] ([Formula: see text] stands for [Formula: see text], [Formula: see text], or [Formula: see text]). Integration of these formulas yields some Standard Model histogram distributions of the decay [Formula: see text] which are compared with corresponding Monte Carlo simulated distributions obtained by ATLAS and with ATLAS experimental data.