Efficient Identification of Boosted Semileptonic Top Quarks at the LHC

Abstract

Top quarks produced in multi-TeV processes will have large Lorentz boosts, and their decay products will be highly collimated. In semileptonic decay modes, this often leads to the merging of the b-jet and the hard lepton according to standard event reconstructions, which can complicate new physics searches. Here we explore ways of efficiently recovering this signal in the muon channel at the LHC. We perform a particle-level study of events with muons produced inside of boosted tops, as well as in generic QCD jets and from W-strahlung off of hard quarks. We characterize the discriminating power of cuts previously explored in the literature, as well two new ones. We find a particularly powerful isolation variable which can potentially reject light QCD jets with hard embedded muons at the 10^3 level while retaining 80~90% of the tops. This can also be fruitfully combined with other cuts for O(1) greater discrimination. For W-strahlung, a simple pT-scaled maximum ΔR cut performs comparably to a highly idealized top-mass reconstruction, rejecting an O(1) fraction of the background with percent-scale loss of signal. Using these results, we suggest a set of well-motivated baseline cuts for any physics analysis involving semileptonic top quarks at TeV-scale momenta, using neither b-tagging nor missing energy as discriminators. We demonstrate the utility of our cuts in searching for resonances in the top-antitop invariant mass spectrum. For example, our results suggest that 100 fb^{-1} of data from a 14 TeV LHC could be used to discover a warped KK gluon up to 4.5 TeV or higher.

arXiv comment28 pages, 15 figures

References in corpus (20)

• PYTHIA 6.4 Physics and Manual
• PYTHIA 6.2 Physics and Manual
• HERWIG 6.5: an event generator for Hadron Emission Reactions With Interfering Gluons (including supersymmetric processes)
• Dispelling the N^3 myth for the Kt jet-finder
• MadGraph/MadEvent v4: The New Web Generation
• RS1, Custodial Isospin and Precision Tests
• Top-tagging: A Method for Identifying Boosted Hadronic Tops
• Fat Jets for a Light Higgs
• Stop Reconstruction with Tagged Tops
• Strategies to Identify Boosted Tops
• The Bulk RS KK-gluon at the LHC
• Top pair invariant mass distribution: a window on new physics
• Top Quark Pairs at High Invariant Mass - A Model-Independent Discriminator of New Physics at the LHC
• Jets with Variable R
• The Little Randall-Sundrum Model at the Large Hadron Collider
• Quantifying the performance of jet definitions for kinematic reconstruction at the LHC
• Measuring the Polarization of Boosted Hadronic Tops
• Search for ttbar resonances in the lepton plus jets final state in ppbar collisions at sqrt{s}=1.96TeV
• Search for New Color-Octet Vector Particle Decaying to ttbar in ppbar Collisions at $\sqrt{s}=1.96$ TeV
• Big Signals of Little Randall-Sundrum Models

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