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Title: Search for anomalous production of events with three or more leptons in pp collisions at sqrt(s) = 8 TeV

Abstract

A search for physics beyond the standard model in events with at least three leptons is presented. The data sample, corresponding to an integrated luminosity of 19.5 inverse femtobarns of proton-proton collisions with center-of-mass energy sqrt(s) = 8 TeV, was collected by the CMS experiment at the LHC during 2012. The data are divided into exclusive categories based on the number of leptons and their flavor, the presence or absence of an opposite-sign, same-flavor lepton pair (OSSF), the invariant mass of the OSSF pair, the presence or absence of a tagged bottom-quark jet, the number of identified hadronically decaying tau leptons, and the magnitude of the missing transverse energy and of the scalar sum of jet transverse momenta. The numbers of observed events are found to be consistent with the expected numbers from standard model processes, and limits are placed on new-physics scenarios that yield multilepton final states. In particular, scenarios that predict Higgs boson production in the context of supersymmetric decay chains are examined. We also place a 95% confidence level upper limit of 1.3% on the branching fraction for the decay of a top quark to a charm quark and a Higgs boson (t to c H), whichmore » translates to a bound on the left- and right-handed top-charm flavor-violating Higgs Yukawa couplings, lambda[H, tc] and lambda[H, ct], respectively, of sqrt(abs(lambda[H, tc])^2 + abs(lambda[H, ct])^2) < 0.21.« less

Authors:
 [1];
  1. Yerevan Physics Institute (Armenia)
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Org.:
CMS Collaboration
OSTI Identifier:
1177134
Report Number(s):
CMS-SUS-13-002; CERN-PH-EP-2014-039; FERMILAB-PUB-14-150-CMS
Journal ID: ISSN: 1550-7998; arXiv eprint number arXiv:1404.5801
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review D; Journal Volume: 90; Journal Issue: 3
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Citation Formats

Chatrchyan, S., and et al.,. Search for anomalous production of events with three or more leptons in pp collisions at sqrt(s) = 8 TeV. United States: N. p., 2014. Web. doi:10.1103/PhysRevD.90.032006.
Chatrchyan, S., & et al.,. Search for anomalous production of events with three or more leptons in pp collisions at sqrt(s) = 8 TeV. United States. doi:10.1103/PhysRevD.90.032006.
Chatrchyan, S., and et al.,. Fri . "Search for anomalous production of events with three or more leptons in pp collisions at sqrt(s) = 8 TeV". United States. doi:10.1103/PhysRevD.90.032006. https://www.osti.gov/servlets/purl/1177134.
@article{osti_1177134,
title = {Search for anomalous production of events with three or more leptons in pp collisions at sqrt(s) = 8 TeV},
author = {Chatrchyan, S. and et al.,},
abstractNote = {A search for physics beyond the standard model in events with at least three leptons is presented. The data sample, corresponding to an integrated luminosity of 19.5 inverse femtobarns of proton-proton collisions with center-of-mass energy sqrt(s) = 8 TeV, was collected by the CMS experiment at the LHC during 2012. The data are divided into exclusive categories based on the number of leptons and their flavor, the presence or absence of an opposite-sign, same-flavor lepton pair (OSSF), the invariant mass of the OSSF pair, the presence or absence of a tagged bottom-quark jet, the number of identified hadronically decaying tau leptons, and the magnitude of the missing transverse energy and of the scalar sum of jet transverse momenta. The numbers of observed events are found to be consistent with the expected numbers from standard model processes, and limits are placed on new-physics scenarios that yield multilepton final states. In particular, scenarios that predict Higgs boson production in the context of supersymmetric decay chains are examined. We also place a 95% confidence level upper limit of 1.3% on the branching fraction for the decay of a top quark to a charm quark and a Higgs boson (t to c H), which translates to a bound on the left- and right-handed top-charm flavor-violating Higgs Yukawa couplings, lambda[H, tc] and lambda[H, ct], respectively, of sqrt(abs(lambda[H, tc])^2 + abs(lambda[H, ct])^2) < 0.21.},
doi = {10.1103/PhysRevD.90.032006},
journal = {Physical Review D},
number = 3,
volume = 90,
place = {United States},
year = {Fri Aug 01 00:00:00 EDT 2014},
month = {Fri Aug 01 00:00:00 EDT 2014}
}
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