A resonance of the Higgs field at 700 GeV and a new phenomenology

Abstract

It has been recently proposed that, besides the known resonance with mass $m_h\sim$ 125 GeV, the Higgs field could exhibit a new excitation with a larger mass $M_h$ related by $M^2_h\sim m^2_h \ln (\Lambda_s/M_h)$, where $\Lambda_s$ is the ultraviolet cutoff of the scalar sector. Lattice simulations of the propagator performed in the 4D Ising limit of the theory are consistent with this two-mass picture and lead to the estimate $M_h\sim 700$ GeV. In spite of its large mass, however, this heavier state would couple to longitudinal vector bosons with the same typical strength of the low-mass state and would thus represent a relatively narrow resonance. In this Letter we argue that this hypothetical new resonance would naturally fit with some excess of 4-lepton events which is observed by ATLAS around 680 GeV.