Universal extra dimensions after Higgs discovery

We show bounds on five- and six-dimensional universal extra dimension (UED) models from the latest results of the Higgs searches at the LHC and from the electroweak precision data for the S and T parameters. We consider the minimal UED model in five dimensions and the ones in six dimensions. The highest possible ultraviolet cutoff scale for each UED model is evaluated from the electroweak vacuum stability by solving the renormalization group equation of the Higgs self-coupling. This scale turns out to be lower than the conventional one obtained from the perturbativity of the gauge coupling. The resultant 95% C.L. lower bounds on the first Kaluza-Klein scale from the LHC results and from the S, T analysis are 600 and 700 GeV in the minimal UED model, while those in the six-dimensional UED models are 800-1300 GeV and 900-1500 GeV, respectively.Comment: 37 pages, 9 figures, 7 tables (v1); 38 pages, 9 figures, 7 tables, with minor modifications, typos fixed, references added (v2); 37 pages, 10 figures, 7 tables, published version in PRD, figures modified, a figure added, typos fixed, a reference added (v3

Constraint on Universal Extra Dimensions from scalar boson searches

We show the bounds on five- and six-dimensional Universal Extra Dimension models from the result of the Higgs boson searches at the Large Hadron Collider and electroweak precision measurement. The latest data released by the ATLAS and the CMS gives the lower bounds on Kaluza-Klein scale which are from 650 GeV to 1350 GeV depending on models from Higgs to diboson/diphoton decay signal. The Higgs production cross section can be enhanced by factor 1.5 in crude estimation, diphoton decay signal is suppressed about 10%. Electroweak precision measurement also gives the lower bounds as from 700 GeV to 1500 GeV.Comment: 4 pages, 1 figure, 1 table, Proceedings of the conference "Rencontres de Moriond EW 2013", La Thuile, Italy, 2-9 Mar. 201