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Title: Bounding the Higgs width at the LHC using full analytic results for $$gg → e^- e^+ \mu^- \mu^+$$

We revisit the hadronic production of the four-lepton final state, e e + μ μ +, through the fusion of initial state gluons. This process is mediated by loops of quarks and we provide first full analytic results for helicity amplitudes that account for both the effects of the quark mass in the loop and off-shell vector bosons. The analytic results have been implemented in the Monte Carlo program MCFM and are both fast, and numerically stable in the region of low Z transverse momentum. We use our results to study the interference between Higgs-mediated and continuum production of four-lepton final states, which is necessary in order to obtain accurate theoretical predictions outside the Higgs resonance region. We have confirmed and extended a recent analysis of Caola and Melnikov that proposes to use a measurement of the off-shell region to constrain the total width of the Higgs boson. Using a simple cut-and-count method, existing LHC data should bound the width at the level of 25-45 times the Standard Model expectation. We investigate the power of using a matrix element method to construct a kinematic discriminant to sharpen the constraint. Furthermore, in our analysis the bound on the Higgsmore » width is improved by a factor of about 1.6 using a simple cut on the MEM discriminant, compared to an invariant mass cut μ 4l > 300 GeV.« less
 [1] ;  [1] ;  [2]
  1. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
  2. The Niels Bohr Institute, Copenhagen (Denmark)
Publication Date:
Report Number(s):
Journal ID: ISSN 1029-8479; arXiv eprint number arXiv:1311.3589
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of High Energy Physics (Online)
Additional Journal Information:
Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2014; Journal Issue: 4; Journal ID: ISSN 1029-8479
Springer Berlin
Research Org:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Country of Publication:
United States
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; QCD phenomenology; hadronic colliders
OSTI Identifier: