Search for an L μ  − L τ gauge boson using Z → 4μ events in proton-proton collisions at s=13 TeV

The CMS collaboration

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

A search for a narrow Z gauge boson with a mass between 5 and 70 GeV resulting from an L μ −L τ U(1) local gauge symmetry is reported. Theories that predict such a particle have been proposed as an explanation of various experimental discrepancies, including the lack of a dark matter signal in direct-detection experiments, tension in the measurement of the anomalous magnetic moment of the muon, and reports of possible lepton flavor universality violation in B meson decays. A data sample of proton-proton collisions at a center-of-mass energy of 13 TeV is used, corresponding to an integrated luminosity of 77.3 fb −1 recorded in 2016 and 2017 by the CMS detector at the LHC. Events containing four muons with an invariant mass near the standard model Z boson mass are analyzed, and the selection is further optimized to be sensitive to the events that may contain Z→Z μμ→4μ decays. The event yields are consistent with the standard model predictions. Upper limits of 10 −8 –10 −7 at 95% confidence level are set on the product of branching fractions B(Z→Z μμ)B(Z →μμ), depending on the Z mass, which excludes a Z boson coupling strength to muons above 0.004–0.3. These are the first dedicated limits on L μ −L τ models at the LHC and result in a significant increase in the excluded model parameter space. The results of this search may also be used to constrain the coupling strength of any light Z gauge boson to muons.

Original languageEnglish
Pages (from-to)345-368
Number of pages24
JournalPhysics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
Volume792
DOIs
Publication statusPublished - 10 May 2019

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muons
bosons
collisions
protons
decay
center of mass
leptons
confidence
dark matter
mesons
magnetic moments
luminosity
detectors
symmetry
products
predictions
energy

Keywords

  • CMS
  • Muons
  • Physics
  • Zprime

ASJC Scopus subject areas

  • Nuclear and High Energy Physics

Cite this

@article{39c3612bcdfe4637a66cf41da9ae6d74,
title = "Search for an L μ  − L τ gauge boson using Z → 4μ events in proton-proton collisions at s=13 TeV",
abstract = "A search for a narrow Z ′ gauge boson with a mass between 5 and 70 GeV resulting from an L μ −L τ U(1) local gauge symmetry is reported. Theories that predict such a particle have been proposed as an explanation of various experimental discrepancies, including the lack of a dark matter signal in direct-detection experiments, tension in the measurement of the anomalous magnetic moment of the muon, and reports of possible lepton flavor universality violation in B meson decays. A data sample of proton-proton collisions at a center-of-mass energy of 13 TeV is used, corresponding to an integrated luminosity of 77.3 fb −1 recorded in 2016 and 2017 by the CMS detector at the LHC. Events containing four muons with an invariant mass near the standard model Z boson mass are analyzed, and the selection is further optimized to be sensitive to the events that may contain Z→Z ′ μμ→4μ decays. The event yields are consistent with the standard model predictions. Upper limits of 10 −8 –10 −7 at 95{\%} confidence level are set on the product of branching fractions B(Z→Z ′ μμ)B(Z ′ →μμ), depending on the Z ′ mass, which excludes a Z ′ boson coupling strength to muons above 0.004–0.3. These are the first dedicated limits on L μ −L τ models at the LHC and result in a significant increase in the excluded model parameter space. The results of this search may also be used to constrain the coupling strength of any light Z ′ gauge boson to muons.",
keywords = "CMS, Muons, Physics, Zprime",
author = "{The CMS collaboration} and Sirunyan, {A. M.} and A. Tumasyan and W. Adam and F. Ambrogi and E. Asilar and T. Bergauer and J. Brandstetter and M. Dragicevic and J. Er{\"o} and {Escalante Del Valle}, A. and M. Flechl and R. Fr{\"u}hwirth and Ghete, {V. M.} and J. Hrubec and M. Jeitler and N. Krammer and I. Kr{\"a}tschmer and D. Liko and T. Madlener and I. Mikulec and N. Rad and H. Rohringer and J. Schieck and R. Sch{\"o}fbeck and M. Spanring and D. Spitzbart and A. Taurok and W. Waltenberger and J. Wittmann and Wulz, {C. E.} and M. Zarucki and V. Chekhovsky and V. Mossolov and {Suarez Gonzalez}, J. and {De Wolf}, {E. A.} and V. Danilov and Kim, {J. S.} and Kim, {J. S.} and Kim, {J. S.} and M. Gavrilenko and A. Zarubin and Y. Ivanov and V. Kim and V. Oreshkin and S. Vavilov and V. Popov and A. Ershov and A. Babaev and S. Baidali and V. Okhotnikov",
year = "2019",
month = "5",
day = "10",
doi = "10.1016/j.physletb.2019.01.072",
language = "English",
volume = "792",
pages = "345--368",
journal = "Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics",
issn = "0370-2693",
publisher = "Elsevier",

}

TY - JOUR

T1 - Search for an L μ  − L τ gauge boson using Z → 4μ events in proton-proton collisions at s=13 TeV

AU - The CMS collaboration

AU - Sirunyan, A. M.

AU - Tumasyan, A.

AU - Adam, W.

AU - Ambrogi, F.

AU - Asilar, E.

AU - Bergauer, T.

AU - Brandstetter, J.

AU - Dragicevic, M.

AU - Erö, J.

AU - Escalante Del Valle, A.

AU - Flechl, M.

AU - Frühwirth, R.

AU - Ghete, V. M.

AU - Hrubec, J.

AU - Jeitler, M.

AU - Krammer, N.

AU - Krätschmer, I.

AU - Liko, D.

AU - Madlener, T.

AU - Mikulec, I.

AU - Rad, N.

AU - Rohringer, H.

AU - Schieck, J.

AU - Schöfbeck, R.

AU - Spanring, M.

AU - Spitzbart, D.

AU - Taurok, A.

AU - Waltenberger, W.

AU - Wittmann, J.

AU - Wulz, C. E.

AU - Zarucki, M.

AU - Chekhovsky, V.

AU - Mossolov, V.

AU - Suarez Gonzalez, J.

AU - De Wolf, E. A.

AU - Danilov, V.

AU - Kim, J. S.

AU - Kim, J. S.

AU - Kim, J. S.

AU - Gavrilenko, M.

AU - Zarubin, A.

AU - Ivanov, Y.

AU - Kim, V.

AU - Oreshkin, V.

AU - Vavilov, S.

AU - Popov, V.

AU - Ershov, A.

AU - Babaev, A.

AU - Baidali, S.

AU - Okhotnikov, V.

PY - 2019/5/10

Y1 - 2019/5/10

N2 - A search for a narrow Z ′ gauge boson with a mass between 5 and 70 GeV resulting from an L μ −L τ U(1) local gauge symmetry is reported. Theories that predict such a particle have been proposed as an explanation of various experimental discrepancies, including the lack of a dark matter signal in direct-detection experiments, tension in the measurement of the anomalous magnetic moment of the muon, and reports of possible lepton flavor universality violation in B meson decays. A data sample of proton-proton collisions at a center-of-mass energy of 13 TeV is used, corresponding to an integrated luminosity of 77.3 fb −1 recorded in 2016 and 2017 by the CMS detector at the LHC. Events containing four muons with an invariant mass near the standard model Z boson mass are analyzed, and the selection is further optimized to be sensitive to the events that may contain Z→Z ′ μμ→4μ decays. The event yields are consistent with the standard model predictions. Upper limits of 10 −8 –10 −7 at 95% confidence level are set on the product of branching fractions B(Z→Z ′ μμ)B(Z ′ →μμ), depending on the Z ′ mass, which excludes a Z ′ boson coupling strength to muons above 0.004–0.3. These are the first dedicated limits on L μ −L τ models at the LHC and result in a significant increase in the excluded model parameter space. The results of this search may also be used to constrain the coupling strength of any light Z ′ gauge boson to muons.

AB - A search for a narrow Z ′ gauge boson with a mass between 5 and 70 GeV resulting from an L μ −L τ U(1) local gauge symmetry is reported. Theories that predict such a particle have been proposed as an explanation of various experimental discrepancies, including the lack of a dark matter signal in direct-detection experiments, tension in the measurement of the anomalous magnetic moment of the muon, and reports of possible lepton flavor universality violation in B meson decays. A data sample of proton-proton collisions at a center-of-mass energy of 13 TeV is used, corresponding to an integrated luminosity of 77.3 fb −1 recorded in 2016 and 2017 by the CMS detector at the LHC. Events containing four muons with an invariant mass near the standard model Z boson mass are analyzed, and the selection is further optimized to be sensitive to the events that may contain Z→Z ′ μμ→4μ decays. The event yields are consistent with the standard model predictions. Upper limits of 10 −8 –10 −7 at 95% confidence level are set on the product of branching fractions B(Z→Z ′ μμ)B(Z ′ →μμ), depending on the Z ′ mass, which excludes a Z ′ boson coupling strength to muons above 0.004–0.3. These are the first dedicated limits on L μ −L τ models at the LHC and result in a significant increase in the excluded model parameter space. The results of this search may also be used to constrain the coupling strength of any light Z ′ gauge boson to muons.

KW - CMS

KW - Muons

KW - Physics

KW - Zprime

UR - http://www.scopus.com/inward/record.url?scp=85064326204&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85064326204&partnerID=8YFLogxK

U2 - 10.1016/j.physletb.2019.01.072

DO - 10.1016/j.physletb.2019.01.072

M3 - Article

VL - 792

SP - 345

EP - 368

JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

SN - 0370-2693

ER -