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arXiv · 1511.05990

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.

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Keith Pedersen, Zack Sullivan. 2015-12-22. Mu_x boosted-bottom-jet tagging and Z-prime boson searches. https://doi.org/10.1103/physrevd.93.014014

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