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Abstract:

A search for flavour-changing neutral-current processes in top-quark decays is presented. Data collected with the ATLAS detector from proton-proton collisions at the Large Hadron Collider at a centre-of-mass energy of s=13 TeV, corresponding to an integrated luminosity of 36.1 fb −1 , are analysed. The search is performed using top-quark pair events, with one top quark decaying through the t → qZ (q = u, c) flavour-changing neutral-current channel, and the other through the dominant Standard Model mode t → bW. Only Z boson decays into charged leptons and leptonic W boson decays are considered as signal. Consequently, the final-state topology is characterized by the presence of three isolated charged leptons (electrons or muons), at least two jets, one of the jets originating from a b-quark, and missing transverse momentum from the undetected neutrino. The data are consistent with Standard Model background contributions, and at 95% confidence level the search sets observed (expected) upper limits of 1.7 × 10 −4 (2.4 × 10 −4 ) on the t → uZ branching ratio and 2.4 × 10 −4 (3.2 × 10 −4 ) on the t → cZ branching ratio, constituting the most stringent limits to date.[Figure not available: see fulltext.]. © 2018, The Author(s).

Registro:

Documento: Artículo
Título:Search for flavour-changing neutral current top-quark decays t → qZ in proton-proton collisions at √s=13 TeV with the ATLAS detector
Autor:Aaboud, M. et al.
Este artículo contiene 2870 autores, consultelos en el artículo en formato pdf.
Filiación: Este artículo contiene 2870 autores con sus filiaciones, consultelas en el artículo en formato pdf.
Palabras clave:Hadron-Hadron scattering (experiments)
Año:2018
Volumen:2018
Número:7
DOI: http://dx.doi.org/10.1007/JHEP07(2018)176
Título revista:Journal of High Energy Physics
Título revista abreviado:J. High Energy Phys.
ISSN:11266708
Registro:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_11266708_v2018_n7_p_Aaboud

Referencias:

  • (2014) First Combination of Tevatron and LHC Measurements of the Top-Quark Mass, , ATLAS-CONF-2014-008
  • Glashow, S.L., Iliopoulos, J., Maiani, L., Weak interactions with lepton-hadron symmetry (1970) Phys. Rev., 500, p. 1285. , [INSPIRE]
  • Aguilar-Saavedra, J.A., Top flavor-changing neutral interactions: Theoretical expectations and experimental detection (2004) Acta Phys. Polon. B, 35, p. 2695. , INSPIRE
  • Aguilar-Saavedra, J.A., Effects of mixing with quark singlets (2003) Phys. Rev. D, 67. , INSPIRE
  • Aguilar-Saavedra, J.A., Effects of mixing with quark singlets (2004) Phys. Rev. D, 69
  • Atwood, D., Reina, L., Soni, A., Phenomenology of two Higgs doublet models with flavor changing neutral currents (1997) Phys. Rev. D, 55, p. 3156. , hep-ph/9609279, INSPIRE, and, (,), [,] [,]
  • Cao, J.J., SUSY-induced FCNC top-quark processes at the Large Hadron Collider (2007) Phys. Rev. D, 75. , INSPIRE
  • Yang, J.M., Young, B.-L., Zhang, X., Flavor changing top quark decays in r parity violating SUSY (1998) Phys. Rev. D, 58. , INSPIRE
  • Agashe, K., Perez, G., Soni, A., Collider signals of top quark flavor violation from a warped extra dimension (2007) Phys. Rev. D, 75, p. 15002. , INSPIRE
  • Hung, P.Q., Lin, Y.-X., Nugroho, C.S., Yuan, T.-C., Top quark rare decays via loop-induced FCNC interactions in extended mirror fermion model (2018) Nucl. Phys., B 927, p. 166. , [] [INSPIRE]
  • Agashe, K., Snowmass 2013 Top Quark Working Group Report
  • Heister, A., Search for single top production in e + e − collisions at √s up to 209-GeV (2002) Phys. Lett. B, 543, p. 173. , INSPIRE
  • Abdallah, J., [CR12] DELPHI collaboration, ., Search for single top production via FCNC at LEP at √s = 189 GeV to 208 GeV, Phys. Lett. B 590 (2004) 21 [hep-ex/0404014] [INSPIRE]; Abbiendi, G., Search for single top quark production at LEP-2 (2001) Phys. Lett. B, 521, p. 181. , [INSPIRE]
  • Achard, P., Search for single top production at LEP (2002) Phys. Lett. B, 549, p. 290. , INSPIRE
  • (2001) Search for single top production via flavour changing neutral currents: Preliminary combined results of the LEP experiments, , Exotica-WG-2001-01
  • Abramowicz, H., Search for single-top production in ep collisions at HERA (2012) Phys. Lett. B, 708, p. 27. , INSPIRE
  • Aaltonen, T., Search for the flavor changing neutral current decay t → Zq in p p ¯ collisions at √s = 1.96 TeV (2008) Phys. Rev. Lett, 101, p. 192002. , INSPIRE
  • Abazov, V.M., Search for flavor changing neutral currents in decays of top quarks (2011) Phys. Lett. B, 701, p. 313. , INSPIRE
  • A search for flavour changing neutral currents in top-quark decays in pp collision data collected with the ATLAS detector at √s = 7 TeV (2012) JHEP, 9, p. 139. , [INSPIRE]
  • Search for flavour-changing neutral current top-quark decays to qZ in pp collision data collected with the ATLAS detector at √s = 8 TeV (2016) Eur. Phys. J. C, 76, p. 12. , INSPIRE
  • Search for flavor-changing neutral currents in top-quark decays t → Zq in pp collisions at √s = 8 TeV (2014) Phys. Rev. Lett, 112, p. 171802. , [INSPIRE]
  • (2017) Search for associated production of a Z boson with a single top quark and for tZ flavour-changing interactions in pp collisions at √s = 8 TeV, JHEP07, p. 003. , INSPIRE
  • The ATLAS experiment at the CERN Large Hadron Collider (2008) JINST, 3. , INSPIRE
  • ATLAS insertable B-layer technical design report (2010) ATLAS-TDR-19
  • (2012) ATLAS insertable B-layer technical design report addendum, , ATLAS-TDR-19-ADD-1
  • (2015) Eur. Phys. J, C 77, p. 317. , INSPIRE
  • Cacciari, M., Top-pair production at hadron colliders with next-to-next-to-leading logarithmic soft-gluon resummation (2012) Phys. Lett., B 710, p. 612. , [] [INSPIRE]
  • Bärnreuther, P., Czakon, M., Mitov, A., Percent level precision physics at the Tevatron: first genuine NNLO QCD corrections to qq¯ → tt¯ + X (2012) Phys. Rev. Lett., 109, p. 132001. , [] [INSPIRE]
  • Czakon, M., Mitov, A., NNLO corrections to top-pair production at hadron colliders: the all-fermionic scattering channels (2012) JHEP, 12, p. 054. , [] [INSPIRE]
  • Czakon, M., Mitov, A., NNLO corrections to top pair production at hadron colliders: the quark-gluon reaction (2013) JHEP, 1, p. 080. , [] [INSPIRE]
  • Czakon, M., Fiedler, P., Mitov, A., Total top-quark pair-production cross section at hadron colliders through O(α S 4 ) (2013) Phys. Rev. Lett., 110, p. 252004. , [] [INSPIRE]
  • Czakon, M., Mitov, A., Top++: a program for the calculation of the top-pair cross-section at hadron colliders (2014) Comput. Phys. Commun., 185, p. 2930. , [] [INSPIRE]
  • Botje, M., The PDF4LHC Working Group Interim Recommendations
  • Martin, A.D., Stirling, W.J., Thorne, R.S., Watt, G., Parton distributions for the LHC (2009) Eur. Phys. J., 100, p. 189. , [] [INSPIRE]
  • Martin, A.D., Stirling, W.J., Thorne, R.S., Watt, G., Uncertainties on α s in global PDF analyses and implications for predicted hadronic cross sections (2009) Eur. Phys. J. C, 64, p. 653. , [INSPIRE]
  • Lai, H.-L., New parton distributions for collider physics (2010) Phys. Rev., 500. , [] [INSPIRE]
  • Gao, J., CT10 next-to-next-to-leading order global analysis of QCD (2014) Phys. Rev. D, 89. , [INSPIRE]
  • Ball, R.D., Parton distributions with LHC data (2013) Nucl. Phys., B 867, p. 244. , [] [INSPIRE]
  • Alwall, J., The automated computation of tree-level and next-to-leading order differential cross sections and their matching to parton shower simulations (2014) JHEP, 7, p. 079. , [] [INSPIRE]
  • Sjöstrand, T., An introduction to PYTHIA 8.2 (2015) Comput. Phys. Commun, 191, p. 159. , INSPIRE
  • (2014) ATLAS run 1 PYTHIA8 tunes, , ATL-PHYS-PUB-2014-021
  • Ball, R.D., Parton distributions for the LHC Run II (2015) JHEP, 4. , INSPIRE
  • de Florian, D., Handbook of LHC Higgs Cross Sections: 4 Deciphering the Nature of the Higgs Sector, , INSPIRE
  • Frixione, S., Single-top hadroproduction in association with a W boson (2008) JHEP, 7, p. 029. , [] [INSPIRE]
  • Gleisberg, T., Event generation with SHERPA 1.1 (2009) JHEP, 2, p. 7. , [INSPIRE]
  • Gleisberg, T., Hoeche, S., Comix, a new matrix element generator (2008) JHEP, 12, p. 039. , [] [INSPIRE]
  • Cascioli, F., Maierhofer, P., Pozzorini, S., Scattering amplitudes with open loops (2012) Phys. Rev. Lett., 108, p. 111601. , [] [INSPIRE]
  • Hoeche, S., QCD matrix elements + parton showers: The NLO case (2013) JHEP, 4, p. 027. , [] [INSPIRE]
  • Alioli, S., Nason, P., Oleari, C., Re, E., A general framework for implementing NLO calculations in shower Monte Carlo programs: the POWHEG BOX (2010) JHEP, 6, p. 043. , [] [INSPIRE]
  • Davidson, N., Przedzinski, T., Was, Z., PHOTOS interface in C++: technical and physics documentation (2016) Comput. Phys. Commun., 199, p. 86. , [] [INSPIRE]
  • (2012) Summary of ATLAS PYTHIA 8 tunes, , ATL-PHYS-PUB-2012-003
  • Agostinelli, S., GEANT4: A simulation toolkit (2003) Nucl. Instrum. Meth. A, 506, p. 250. , [INSPIRE]
  • The ATLAS simulation infrastructure (2010) Eur. Phys. J. C, 70, p. 823. , INSPIRE
  • Pumplin, J., New generation of parton distributions with uncertainties from global QCD analysis (2002) JHEP, 7, p. 012. , INSPIRE
  • Measurement of the Z/γ * boson transverse momentum distribution in pp collisions at √s = 7 TeV with the ATLAS detector (2014) JHEP, 9, p. 145. , [INSPIRE]
  • Sjöstrand, T., Mrenna, S., Skands, P.Z., PYTHIA 6.4 physics and manual (2006) JHEP, 5. , INSPIRE
  • Skands, P.Z., Tuning Monte Carlo generators: the Perugia tunes (2010) Phys. Rev., 500. , [] [INSPIRE]
  • Bahr, M., HERWIG++ physics and manual (2008) Eur. Phys. J., 100, p. 639. , [] [INSPIRE]
  • Gieseke, S., Rohr, C., Siódmok, A., Colour reconnections in HERWIG++ (2012) Eur. Phys. J., 100, p. 2225. , [] [INSPIRE]
  • Bellm, J., HERWIG 7.0/HERWIG++ 3.0 release note (2016) Eur. Phys. J. C, 76, p. 196. , INSPIRE
  • Harland-Lang, L.A., Martin, A.D., Motylinski, P., Thorne, R.S., Parton distributions in the LHC era: MMHT 2014 PDFs (2015) Eur. Phys. J., 100, p. 204. , [] [INSPIRE]
  • LHC proton-proton collision data (2011) Eur. Phys. J. C, 74, p. 2941. , [INSPIRE]
  • Muon reconstruction performance of the ATLAS detector in proton-proton collision data at √s = 13 TeV (2016) Eur. Phys. J. C, 76, p. 292. , INSPIRE
  • Topological cell clustering in the ATLAS calorimeters and its performance in LHC Run 1 (2017) Eur. Phys. J. C, 77, p. 490. , INSPIRE
  • Cacciari, M., Salam, G.P., Soyez, G., The anti-k t jet clustering algorithm (2008) JHEP, 4, p. 063. , [] [INSPIRE]
  • Cacciari, M., Salam, G.P., Soyez, G., FastJet user manual (2012) Eur. Phys. J., 100, p. 1896. , [] [INSPIRE]
  • Cacciari, M., Salam, G.P., Pileup subtraction using jet areas (2008) Phys. Lett., B 659, p. 119. , [] [INSPIRE]
  • Jet energy scale measurements and their systematic uncertainties in proton-proton collisions at √s = 13 TeV with the ATLAS detector (2017) Phys. Rev. D, 96. , INSPIRE
  • Performance of pile-up mitigation techniques for jets in pp collisions at √s = 8 TeV using the ATLAS detector (2016) Eur. Phys. J. C, 76, p. 581. , INSPIRE
  • Performance of b-jet identification in the ATLAS experiment (2016) JINST, 11. , INSPIRE
  • Optimisation of the ATLAS b-tagging performance for the 2016 LHC Run (2016) ATL-PHYS-PUB-2016-012
  • Performance of missing transverse momentum reconstruction in proton-proton collisions at 7 TeV with ATLAS (2012) Eur. Phys. J., C 72, p. 1844. , [INSPIRE]
  • Performance of algorithms that reconstruct missing transverse momentum in √s = 8 TeV proton-proton collisions in the ATLAS detector (2017) Eur. Phys. J. C, 77, p. 241. , INSPIRE
  • Bukin, A.D., Fitting Function for Asymmetric Peaks
  • (2017) Measurement of the production cross-section of a single top quark in association with a Z boson in proton-proton collisions at 13 TeV with the ATLAS detector, , CERN-EP-2017-188
  • Measurement of the W ± Z boson pair-production cross section in pp collisions at √s = 13 TeV with the ATLAS Detector (2016) Phys. Lett. B, pp. 762-771. , [INSPIRE]
  • Hoche, S., Krauss, F., Schonherr, M., Siegert, F., NLO matrix elements and truncated showers (2011) JHEP, 8, p. 123. , [] [INSPIRE]
  • Measurement of the t t ¯ Z and t t ¯ W production cross sections in multilepton final states using 3.2 fb −1 of pp collisions at √s = 13 TeV with the ATLAS detector (2017) Eur. Phys. J. C, 77, p. 40. , INSPIRE
  • Electron and photon energy calibration with the ATLAS detector using LHC Run 1 data (2014) Eur. Phys. J. C, 74, p. 3071. , [INSPIRE]
  • Measurement of the muon reconstruction performance of the ATLAS detector using 2011 and 2012 LHC proton-proton collision data (2014) Eur. Phys. J. C, 74, p. 3130. , INSPIRE
  • Jet energy measurement and its systematic uncertainty in proton-proton collisions at √s = 7 TeV with the ATLAS detector (2015) Eur. Phys. J. C, 75, p. 17. , INSPIRE
  • Jet energy resolution in proton-proton collisions at √s = 7 TeV recorded in 2010 with the ATLAS detector (2013) Eur. Phys. J. C, 73, p. 2306. , [INSPIRE]
  • Luminosity determination in pp collisions at √s = 7 TeV using the ATLAS detector at the LHC (2011) Eur. Phys. J. C, 71, p. 1630. , INSPIRE
  • Read, A.L., Presentation of search results: the CL s technique (2002) J. Phys., G 28, p. 2693. , [INSPIRE]
  • Junk, T., Confidence level computation for combining searches with small statistics (1999) Nucl. Instrum. Meth. A, 434, p. 435. , INSPIRE
  • Cowan, G., Cranmer, K., Gross, E., Vitells, O., Asymptotic formulae for likelihood-based tests of new physics (2011) Eur. Phys. J. C, 71, p. 1554. , [INSPIRE]
  • Cowan, G., Cranmer, K., Gross, E., Vitells, O., Asymptotic formulae for likelihood-based tests of new physics (2013) Eur. Phys. J. C, 73, p. 2501
  • Verkerke, W., Kirkby, D.P., (2003) The RooFit toolkit for data modeling, , eConf C 0303241, MOLT007, INSPIRE
  • Moneta, L., The RooStats project Pos(Acat2010), , [INSPIRE]
  • Degrande, C., Automatic computations at next-to-leading order in QCD for top-quark flavor-changing neutral processes (2015) Phys. Rev., 500. , [] [INSPIRE]
  • Durieux, G., Maltoni, F., Zhang, C., Global approach to top-quark flavor-changing interactions (2015) Phys. Rev., 500. , [] [INSPIRE]
  • (2016) ATLAS Computing Acknowledgements, , ATL-GEN-PUB-2016-002

Citas:

---------- APA ----------
(2018) . Search for flavour-changing neutral current top-quark decays t → qZ in proton-proton collisions at √s=13 TeV with the ATLAS detector. Journal of High Energy Physics, 2018(7).
http://dx.doi.org/10.1007/JHEP07(2018)176
---------- CHICAGO ----------
Aaboud, M. "Search for flavour-changing neutral current top-quark decays t → qZ in proton-proton collisions at √s=13 TeV with the ATLAS detector" . Journal of High Energy Physics 2018, no. 7 (2018).
http://dx.doi.org/10.1007/JHEP07(2018)176
---------- MLA ----------
Aaboud, M. "Search for flavour-changing neutral current top-quark decays t → qZ in proton-proton collisions at √s=13 TeV with the ATLAS detector" . Journal of High Energy Physics, vol. 2018, no. 7, 2018.
http://dx.doi.org/10.1007/JHEP07(2018)176
---------- VANCOUVER ----------
Aaboud, M. Search for flavour-changing neutral current top-quark decays t → qZ in proton-proton collisions at √s=13 TeV with the ATLAS detector. J. High Energy Phys. 2018;2018(7).
http://dx.doi.org/10.1007/JHEP07(2018)176