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Title: Search for standard model production of four top quarks with same-sign and multilepton final states in proton-proton collisions at $$\sqrt{s} =$$ 13 TeV

Abstract

A search for standard model production of four top quarks ($$\mathrm{t}\overline{\mathrm{t}}\mathrm{t}\overline{\mathrm{t}})$$ is reported using events containing at least three leptons (e, $$\mu$$) or a same-sign lepton pair. The events are produced in proton-proton collisions at a center-of-mass energy of 13 TeV at the LHC, and the data sample, recorded in 2016, corresponds to an integrated luminosity of 35.9 fb$$^{-1}$$. Jet multiplicity and flavor are used to enhance signal sensitivity, and dedicated control regions are used to constrain the dominant backgrounds. The observed and expected signal significances are, respectively, 1.6 and 1.0 standard deviations, and the $$\mathrm{t}\overline{\mathrm{t}}\mathrm{t}\overline{\mathrm{t}}$$ cross section is measured to be 16.9$$^{+13.8}_{-11.4}$$ fb, in agreement with next-to-leading-order standard model predictions. These results are also used to constrain the Yukawa coupling between the top quark and the Higgs boson to be less than 2.1 times its expected standard model value at 95% confidence level.

Authors:
;
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1409378
Report Number(s):
FERMILAB-PUB-17-537-CMS; CMS-TOP-17-009; CERN-EP-2017-262; arXiv:1710.10614
1633423
DOE Contract Number:
AC02-07CH11359
Resource Type:
Journal Article
Resource Relation:
Journal Name: TBD
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Citation Formats

Sirunyan, Albert M, and et al. Search for standard model production of four top quarks with same-sign and multilepton final states in proton-proton collisions at $\sqrt{s} =$ 13 TeV. United States: N. p., 2017. Web.
Sirunyan, Albert M, & et al. Search for standard model production of four top quarks with same-sign and multilepton final states in proton-proton collisions at $\sqrt{s} =$ 13 TeV. United States.
Sirunyan, Albert M, and et al. 2017. "Search for standard model production of four top quarks with same-sign and multilepton final states in proton-proton collisions at $\sqrt{s} =$ 13 TeV". United States. doi:. https://www.osti.gov/servlets/purl/1409378.
@article{osti_1409378,
title = {Search for standard model production of four top quarks with same-sign and multilepton final states in proton-proton collisions at $\sqrt{s} =$ 13 TeV},
author = {Sirunyan, Albert M and et al.},
abstractNote = {A search for standard model production of four top quarks ($\mathrm{t}\overline{\mathrm{t}}\mathrm{t}\overline{\mathrm{t}})$ is reported using events containing at least three leptons (e, $\mu$) or a same-sign lepton pair. The events are produced in proton-proton collisions at a center-of-mass energy of 13 TeV at the LHC, and the data sample, recorded in 2016, corresponds to an integrated luminosity of 35.9 fb$^{-1}$. Jet multiplicity and flavor are used to enhance signal sensitivity, and dedicated control regions are used to constrain the dominant backgrounds. The observed and expected signal significances are, respectively, 1.6 and 1.0 standard deviations, and the $\mathrm{t}\overline{\mathrm{t}}\mathrm{t}\overline{\mathrm{t}}$ cross section is measured to be 16.9$^{+13.8}_{-11.4}$ fb, in agreement with next-to-leading-order standard model predictions. These results are also used to constrain the Yukawa coupling between the top quark and the Higgs boson to be less than 2.1 times its expected standard model value at 95% confidence level.},
doi = {},
journal = {TBD},
number = ,
volume = ,
place = {United States},
year = 2017,
month =
}
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