Minimal matter at the large hadron collider

We classify all possible new U(1)Y⊗SU(2)L⊗SU(3)cU(1)Y⊗SU(2)L⊗SU(3)c multiplets that can couple to pairs of SM particles. Assuming that production of such new particles is dominated by their gauge interactions we study their signals at LHC, finding the following five main classes: (i) lepto-quark 2ℓ2q2ℓ2q signals; (ii) di-lepton 4ℓ signals; (iii) di-quarks 4j   signals, (iv) heavy-lepton 2ℓ2V2ℓ2V signals and (v) heavy quarks 2j2V2j2V signals, where V denotes heavy SM vectors (with W being associated to exotic fermions). In each case we outline the most promising final states, the SM backgrounds and propose the needed searches.