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A search is presented for a singly produced excited bottom quark (b*) decaying to a top quark and a W boson in the all-hadronic, lepton+jets, and dilepton final states in proton-proton collisions at s=8(Formula Presented.)TeV recorded by the CMS experiment at the CERN LHC. Data corresponding to an integrated luminosity of 19.7 fb−1 are used. No significant excess of events is observed with respect to standard model expectations. We set limits at 95% confidence on the product of the b* quark production cross section and its branching fraction to tW. The cross section limits are interpreted for scenarios including left-handed, right-handed, and vector-like couplings of the b* quark and are presented in the two-dimensional coupling plane based on the production and decay coupling constants. The masses of the left-handed, right-handed, and vector-like b* quark states are excluded at 95% confidence below 1390, 1430, and 1530 GeV, respectively, for benchmark couplings. This analysis gives the most stringent limits on the mass of the b∗ quark to date.[Figure not available: see fulltext.]
The CMS collaboration, Khachatryan, V., Sirunyan, A. M., Tumasyan, A., Adam, W., Asilar, E., … Woods, N. (2016). Search for the production of an excited bottom quark decaying to tW in proton-proton collisions at (Formula Presented.) TeV. Journal of High Energy Physics, 2016(1), 1–44. https://doi.org/10.1007/JHEP01(2016)166