Back to 1974: The $\mathcal{Q}$-onium

Abstract

We show that the 750 GeV di-photon excess could be explained by the $\mathcal{Q}-$onium system of a new QCD-like theory with fermions vectorial under the SM. Beside the spin-0 di-photon singlet this scenario predicts almost degenerate colored scalars and spin-1 resonances analogous to the $J/\Psi$ in QCD. All these states are within the reach of the LHC. An apparent large width can be explained as due to production of excited states with splitting $\Delta m\sim \Gamma$.

Comments: 6 pages. v2: QCD effects and splitting of SU(2) multiplets added. v3: final version to appear in PLB