Multi-boson splashes at future colliders from electroweak compositeness

We propose a new collider signature for the composite origin of the electroweak symmetry breaking of the standard model. The Higgs sector consists of new fundamental fermions (hyper-quarks), which confine at a hadronization scale ${\mathrm{\Lambda }}_{HC}\sim$ few TeV. At energies above ${\mathrm{\Lambda }}_{HC}$, the Drell-Yan production of the hyper-quarks leads to the production of a few electroweak bosons, in analogy with hadron production in QCD at $e^{+}{e}^{-}\to q\bar{q}$ around a few GeV. We show that this regime can be probed at future colliders, namely the proposed 100 TeV hadron collider (FCC-hh) and a 10 TeV muon collider. Together with the direct discovery of electroweak resonances, the multi electroweak boson signature provides a smoking gun for Higgs compositeness.