Constraints on universal extra dimensions from W′ searches

We obtain constraints on three universal extra-dimensional models utilizing limits from the CMS Collaboration on W' production and decay into a single-top-quark final state. We find a weak constraint on the minimal universal extra-dimensional model due to small Kaluza-Klein number violating terms. In contrast, the W' search puts a strong limit on the size of the Dirac mass term of the quarks in split universal extra-dimension models. In nonminimal universal extra-dimension models, the W' search constrains the splitting between the boundary-localized kinetic terms of the gauge bosons and the quarks. Each of these bounds can be translated into constraints on the mass splitting between the Kaluza-Klein excitations of the SU(2) charged quarks and the Klauza-Klein excitations of the W boson.