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Title: Search for direct pair production of scalar top quarks in the single- and dilepton channels in proton-proton collisions at $$\sqrt{s}$$ = 8 TeV

Abstract

Results are reported from a search for the top squark $$ \tilde{t}_1 $$, the lighter of the two supersymmetric partners of the top quark. The data sample corresponds to 19.7 fb$$^{-1}$$ of proton-proton collisions at $$\sqrt{s} =$$ 8 TeV collected with the CMS detector at the LHC. The search targets $$ \tilde{t}_1 \to \mathrm{b} \tilde{\chi}^{\pm}_1$$ and $$ \tilde{t}_1 \to \mathrm{t}^{(*)} \tilde{\chi}^0_1$$ decay modes, where $$\tilde{\chi}^{\pm}_1$$ and $$\tilde{\chi}^0_1$$ are the lightest chargino and neutralino, respectively. The reconstructed final state consists of jets, b jets, missing transverse energy, and either one or two leptons. Leading backgrounds are determined from data. No significant excess in data is observed above the expectation from standard model processes. The results exclude a region of the two-dimensional plane of possible $$ \tilde{t}_1 $$ and $$\tilde{\chi}^0_1 $$ masses. The highest excluded $$ \tilde{t}_1 $$ and $$ \tilde{\chi}^0_1$$ masses are about 700 GeV and 250 GeV, respectively.

Authors:
 [1]
  1. Yerevan Physics Inst. (YerPhI), Yerevan (Armenia). et al.
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1244497
Report Number(s):
CMS-SUS-14-015; CERN-PH-EP-2016-004; CERN-EP-2016-004; arXiv:1602.03169; FERMILAB-PUB-16-062-CMS
Journal ID: ISSN 1029-8479; 1420556; TRN: US1601637
Grant/Contract Number:
AC02-07CH11359
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of High Energy Physics (Online)
Additional Journal Information:
Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2016; Journal Issue: 7; Journal ID: ISSN 1029-8479
Publisher:
Springer Berlin
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; Hadron-Hadron scattering (experiments); supersymmetry; top quark

Citation Formats

Khachatryan, Vardan. Search for direct pair production of scalar top quarks in the single- and dilepton channels in proton-proton collisions at $\sqrt{s}$ = 8 TeV. United States: N. p., 2016. Web. doi:10.1007/JHEP07(2016)027.
Khachatryan, Vardan. Search for direct pair production of scalar top quarks in the single- and dilepton channels in proton-proton collisions at $\sqrt{s}$ = 8 TeV. United States. doi:10.1007/JHEP07(2016)027.
Khachatryan, Vardan. 2016. "Search for direct pair production of scalar top quarks in the single- and dilepton channels in proton-proton collisions at $\sqrt{s}$ = 8 TeV". United States. doi:10.1007/JHEP07(2016)027. https://www.osti.gov/servlets/purl/1244497.
@article{osti_1244497,
title = {Search for direct pair production of scalar top quarks in the single- and dilepton channels in proton-proton collisions at $\sqrt{s}$ = 8 TeV},
author = {Khachatryan, Vardan},
abstractNote = {Results are reported from a search for the top squark $ \tilde{t}_1 $, the lighter of the two supersymmetric partners of the top quark. The data sample corresponds to 19.7 fb$^{-1}$ of proton-proton collisions at $\sqrt{s} =$ 8 TeV collected with the CMS detector at the LHC. The search targets $ \tilde{t}_1 \to \mathrm{b} \tilde{\chi}^{\pm}_1$ and $ \tilde{t}_1 \to \mathrm{t}^{(*)} \tilde{\chi}^0_1$ decay modes, where $\tilde{\chi}^{\pm}_1$ and $\tilde{\chi}^0_1$ are the lightest chargino and neutralino, respectively. The reconstructed final state consists of jets, b jets, missing transverse energy, and either one or two leptons. Leading backgrounds are determined from data. No significant excess in data is observed above the expectation from standard model processes. The results exclude a region of the two-dimensional plane of possible $ \tilde{t}_1 $ and $\tilde{\chi}^0_1 $ masses. The highest excluded $ \tilde{t}_1 $ and $ \tilde{\chi}^0_1$ masses are about 700 GeV and 250 GeV, respectively.},
doi = {10.1007/JHEP07(2016)027},
journal = {Journal of High Energy Physics (Online)},
number = 7,
volume = 2016,
place = {United States},
year = 2016,
month = 7
}

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