Logo
ScienceStack
Table of Contents
Fetching ...
Sign In

Using jet mass to discover vector quarks at the LHC

Witold Skiba, David Tucker-Smith

TL;DR

This work demonstrates that jet mass distributions can reveal heavy vector-like quarks at the LHC when their decays yield highly boosted gauge bosons and top quarks. By focusing on a vector-quark doublet with mass around 1 TeV and analyzing both single-lepton and dilepton final states, the authors show that jet masses cluster near mW and mt, and that pairing W-like jets with top-like jets yields a peak near the vector-quark mass. Their simulations, including detector effects, find signal significances exceeding 5σ with 100 fb⁻¹, indicating jet-mass analyses as a powerful complementary approach to traditional invariant-mass searches. The results suggest broader applicability of jet-mass techniques to other new-physics scenarios involving boosted heavy states.

Abstract

We illustrate the utility of jet mass distributions as probes of new physics at the LHC, focusing on a heavy vector-quark doublet that mixes with the top as a concrete example. For 1 TeV vector-quark masses, we find that signals with greater than 5 sigma significance can be achieved after 100 fb^-1. More generally, jet mass distributions have the potential to provide signals for heavy states that produce highly boosted weak gauge bosons and/or top quarks.

Using jet mass to discover vector quarks at the LHC

TL;DR

This work demonstrates that jet mass distributions can reveal heavy vector-like quarks at the LHC when their decays yield highly boosted gauge bosons and top quarks. By focusing on a vector-quark doublet with mass around 1 TeV and analyzing both single-lepton and dilepton final states, the authors show that jet masses cluster near mW and mt, and that pairing W-like jets with top-like jets yields a peak near the vector-quark mass. Their simulations, including detector effects, find signal significances exceeding 5σ with 100 fb⁻¹, indicating jet-mass analyses as a powerful complementary approach to traditional invariant-mass searches. The results suggest broader applicability of jet-mass techniques to other new-physics scenarios involving boosted heavy states.

Abstract

We illustrate the utility of jet mass distributions as probes of new physics at the LHC, focusing on a heavy vector-quark doublet that mixes with the top as a concrete example. For 1 TeV vector-quark masses, we find that signals with greater than 5 sigma significance can be achieved after 100 fb^-1. More generally, jet mass distributions have the potential to provide signals for heavy states that produce highly boosted weak gauge bosons and/or top quarks.

Paper Structure

This paper contains 5 sections, 9 equations, 5 figures, 2 tables.

Table of Contents

  1. introduction
  2. the model
  3. single lepton analysis
  4. dilepton analysis
  5. conclusions

Figures (5)

  • Figure 1: Jet mass distributions for jets with $p_T>350$ GeV, for events that pass the cuts described in the text. We take 100 fb$^{-1}$ for the integrated luminosity.
  • Figure 2: Jet mass distributions for the signal plus total background and for total background alone, for events that pass the cuts described in the text. As before, only jets having $p_T>350$ GeV are included for each qualifying event, and we take 100 fb$^{-1}$ for the integrated luminosity.
  • Figure 3: Invariant mass distribution for pairs of $W$ and top candidates, after 100 fb$^{-1}$ of integrated luminosity.
  • Figure 4: Jet mass distributions for the signal plus total background and for total background alone, for events passing the cuts in the dilepton analysis. Only jets having $p_T>300$ GeV are included for each qualifying event, and we take 100 fb$^{-1}$ for the integrated luminosity.
  • Figure 5: Same as figure \ref{['fig:dilepF']}, but with a $b$-tag requirement.