Colorful imprints of heavy states in the electroweak effective theory

Abstract

Abstract We analyze heavy states from generic ultraviolet completions of the Standard Model in a model-independent way and investigate their implications on the low-energy couplings of the electroweak effective theory. We build a general effective Lagrangian, implementing the electroweak symmetry breaking SU(2) L ⊗ SU(2) R → SU(2) L+R with a non-linear Nambu-Goldstone realization, which couples the known particles to the heavy states. We generalize the formalism developed in previous works [1, 2] to include colored resonances, both of bosonic and fermionic type. We study bosonic heavy states with J P = 0± and J P = 1±, in singlet or triplet SU(2) L+R representations and in singlet or octet representations of SU(3) C , and fermionic resonances with $$ J=\frac{1}{2} $$ J = 1 2 that are electroweak doublets and QCD triplets or singlets. Integrating out the heavy scales, we determine the complete pattern of low-energy couplings at the lowest non-trivial order. Some specific types of (strongly- and weakly-coupled) ultraviolet completions are discussed to illustrate the generality of our approach and to make contact with current experimental searches.