Mu_x boosted-bottom-jet tagging and Z-prime boson searches

Abstract

We present a new technique for tagging heavy-flavor jets with p_T > 500 GeV called "mu_x tagging." Current track-based methods of b-jet tagging lose efficiency and experience a large rise in fake rate in the boosted regime. Using muons from B hadron decay, we combine angular information and jet substructure to tag b jets, c jets, light jets, and "light-heavy" jets (those containing B hadrons from gluon splitting). We find tagging efficiencies of epsilon_b = 14%, epsilon_c = 6.5%, epsilon_{light-light} = 0.14%, and epsilon_{light-heavy} = 0.5%, respectively, that are nearly independent of transverse momentum at high energy. We demonstrate the usefulness of this new scheme by examining the discovery potential for multi-TeV leptophobic Z-prime bosons in the boosted-b-tagged dijet channel at the Large Hadron Collider.