Heavy Vector Partners of the Light Composite Higgs

Abstract

If the Higgs boson $H(125)$ is a composite due to new strong interactions at high energy, it has spin-one partners, $\rho_H$ and $a_H$, analogous to the $\rho$ and $a_1$ mesons of QCD. These bosons are heavy, their mass determined by the strong interaction scale. The strongly interacting particles light enough for $\rho_H$ and $a_H$ to decay to are the longitudinal weak bosons $V_L = W_L,\, Z_L$ and the Higgs boson $H$. These decay signatures are consistent with resonant diboson excesses recently reported near 2 TeV by ATLAS and CMS. We calculate $\sigma\times BR(\rho_H \to VV) =$ few fb and $\sigma\times BR(a_H \to VH) =$ 0.5-1 fb at $\sqrt{s} =$ 8 TeV, increasing by a factor of 5-7 at 13 TeV. Other tests of the hypothesis of the strong-interaction nature of the diboson resonances are suggested.