Search for W??tb decays in the lepton + jets final state in pp collisions at ?s = 8TeV

Abstract

Results are presented from a search for the production of a heavy gauge boson W? decaying into a top and a bottom quark, using a data set collected by the CMS experiment at ?s = 8TeV and corresponding to an integrated luminosity of 19.5 fb?1. Various models of W?-boson production are studied by allowing for an arbitrary combination of left-and right-handed couplings. The analysis is based on the detection of events with a lepton (e, ?), jets, and missing transverse energy in the final state. No evidence for W?-boson production is found and 95% confidence level upper limits on the production cross section times branching fraction are obtained. For W? bosons with purely right-handed couplings, and for those with left-handed couplings assuming no interference effects, the observed 95% confidence level limit is M(W?) > 2.05TeV. For W? bosons with purely left handed couplings, including interference effects, the observed 95% confidence level limit is M(W?) > 1.84TeV. The results presented in this paper are the most stringent limits published to date