Search for $W'\rightarrow t\bar{b}$ in the lepton plus jets final states with the ATLAS detector at the LHC

This document presents a search for a W' boson, decaying to a top quark and a b quark in an effective coupling approach, using a multivariate method based on boosted decision trees. It reports exclusion limits on the W' ->tbbar cross-section times branching ratio and effective couplings as a function of the W'-boson mass. The search covers W'-boson masses between 0.5 and 3.0 TeV, for right-handed or left-handed W'-boson, with 20.3 fb-1 of proton proton collision data produced by the LHC in 2012, at a center-of-mass energy of 8 TeV and collected by the ATLAS detector.