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Title: Bounding the Higgs Width Through Interferometry

; ;
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC); High Energy Physics (HEP)
OSTI Identifier:
Report Number(s):
Journal ID: ISSN 0031-9007; arXiv:1305.3854
DOE Contract Number:
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 111; Journal Issue: 11
Country of Publication:
United States
Experiment-HEP, Phenomenology-HEP,HEPEX, HEPPH

Citation Formats

Dixon, Lance J., Li, Ye, and /SLAC. Bounding the Higgs Width Through Interferometry. United States: N. p., 2013. Web. doi:10.1103/PhysRevLett.111.111802.
Dixon, Lance J., Li, Ye, & /SLAC. Bounding the Higgs Width Through Interferometry. United States. doi:10.1103/PhysRevLett.111.111802.
Dixon, Lance J., Li, Ye, and /SLAC. Fri . "Bounding the Higgs Width Through Interferometry". United States. doi:10.1103/PhysRevLett.111.111802.
title = {Bounding the Higgs Width Through Interferometry},
author = {Dixon, Lance J. and Li, Ye and /SLAC},
abstractNote = {},
doi = {10.1103/PhysRevLett.111.111802},
journal = {Physical Review Letters},
number = 11,
volume = 111,
place = {United States},
year = {Fri May 24 00:00:00 EDT 2013},
month = {Fri May 24 00:00:00 EDT 2013}
  • We investigate the potential of the process gg → H→ WW to provide bounds on the Higgs width. Recent studies using off-shell H→ ZZ events have shown that Run 1 LHC data can constrain the Higgs width,more » $$\Gamma_H < (25-45) \Gamma_{H}^{\rm SM}$$. Using 20 fb-1 of 8 TeV ATLAS data, we estimate a bound on the Higgs boson width from the WW channel between $$\Gamma_H < (100-500) \Gamma_H^{SM}$$. The large spread in limits is due to the range of cuts applied in the existing experimental analysis. The stricter cuts designed to search for the on-shell Higgs boson limit the potential number of off-shell events, weakening the constraints. As some of the cuts are lifted the bounds improve. We show that there is potential in the high transverse mass region to produce upper bounds of the order of $$(25-50) \Gamma_H^{SM}$$, depending strongly on the level of systematic uncertainty that can be obtained. Thus, if these systematics can be controlled, a constraint on the Higgs boson width from the H → WW$ decay mode can complement a corresponding limit from H → ZZ.« less
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  • We present results for the Standard model description of the four-lepton production, mediated both by Higgs boson production and by other one-loop standard model processes. The description of four-lepton final states in MCFM v6.8 is reviewed, with special reference to the interference effects that can occur for identical species of leptons. We present results both for interference in themore » $l^+l^- l^- l^+$ and in the $$l^-l^+ \nu_l \bar{\nu}_l$$ final state. Prospects for further improvement in the theoretical description of four lepton production are also reviewed.« less
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