Abstract
At the LHC, top quarks can be produced singly with a sizeable rate via electroweak interactions. This process probes a limited set of top-quark electroweak couplings, i.e., the same entering the top-quark decay, yet at higher scales and with a different sensitivity. Requiring the production of a Z or H boson in association with single-top significantly extends the sensitivity of this process to new physics, opening up the unique possibility of testing top-Higgs, top-gauge, triple gauge, gauge-Higgs interactions without being dominated by QCD interactions. We consider tZj and tHj production at the LHC, providing predictions at next-to-leading accuracy in QCD in the framework of the standard model effective field theory, including all relevant operators up to dimension six. We perform the first complete study of the sensitivity to new interactions of these processes, highlighting the interplay and complementarity among tj, tZj and tHj in simultaneously constraining top-quark, triple gauge, and gauge-Higgs interactions in the current and future runs at the LHC.
Article PDF
Similar content being viewed by others
Explore related subjects
Discover the latest articles, news and stories from top researchers in related subjects.Avoid common mistakes on your manuscript.
References
S. Weinberg, Phenomenological lagrangians, Physica A 96 (1979) 327 [INSPIRE].
W. Buchmüller and D. Wyler, Effective lagrangian analysis of new interactions and flavor conservation, Nucl. Phys. B 268 (1986) 621 [INSPIRE].
C.N. Leung, S.T. Love and S. Rao, Low-energy manifestations of a new interaction scale: operator analysis, Z. Phys. C 31 (1986) 433 [INSPIRE].
C. Zhang and F. Maltoni, Top-quark decay into Higgs boson and a light quark at next-to-leading order in QCD, Phys. Rev. D 88 (2013) 054005 [arXiv:1305.7386] [INSPIRE].
C. Zhang, Effective field theory approach to top-quark decay at next-to-leading order in QCD, Phys. Rev. D 90 (2014) 014008 [arXiv:1404.1264] [INSPIRE].
C. Degrande, F. Maltoni, J. Wang and C. Zhang, Automatic computations at next-to-leading order in QCD for top-quark flavor-changing neutral processes, Phys. Rev. D 91 (2015) 034024 [arXiv:1412.5594] [INSPIRE].
D. Buarque Franzosi and C. Zhang, Probing the top-quark chromomagnetic dipole moment at next-to-leading order in QCD, Phys. Rev. D 91 (2015) 114010 [arXiv:1503.08841] [INSPIRE].
C. Zhang, Single top production at next-to-leading order in the standard model effective field theory, Phys. Rev. Lett. 116 (2016) 162002 [arXiv:1601.06163] [INSPIRE].
O. Bessidskaia Bylund et al., Probing top quark neutral couplings in the standard model effective field theory at NLO in QCD, JHEP 05 (2016) 052 [arXiv:1601.08193] [INSPIRE].
F. Maltoni, E. Vryonidou and C. Zhang, Higgs production in association with a top-antitop pair in the standard model effective field theory at NLO in QCD, JHEP 10 (2016) 123 [arXiv:1607.05330] [INSPIRE].
R. Röntsch and M. Schulze, Constraining couplings of top quarks to the Z boson in \( t\overline{t}+Z \) production at the LHC, JHEP 07 (2014) 091 [Erratum ibid. 09 (2015) 132] [arXiv:1404.1005] [INSPIRE].
R. Röntsch and M. Schulze, Probing top-Z dipole moments at the LHC and ILC, JHEP 08 (2015) 044 [arXiv:1501.05939] [INSPIRE].
C. Hartmann and M. Trott, On one-loop corrections in the standard model effective field theory; the Γ(h → γ γ) case, JHEP 07 (2015) 151 [arXiv:1505.02646] [INSPIRE].
M. Ghezzi, R. Gomez-Ambrosio, G. Passarino and S. Uccirati, NLO Higgs effective field theory and κ-framework, JHEP 07 (2015) 175 [arXiv:1505.03706] [INSPIRE].
C. Hartmann and M. Trott, Higgs decay to two photons at one loop in the standard model effective field theory, Phys. Rev. Lett. 115 (2015) 191801 [arXiv:1507.03568] [INSPIRE].
R. Gauld, B.D. Pecjak and D.J. Scott, One-loop corrections to \( h\to b\overline{b} \) and \( h\to \tau \overline{\tau} \) decays in the standard model dimension-6 EFT: four-fermion operators and the large-m t limit, JHEP 05 (2016) 080 [arXiv:1512.02508] [INSPIRE].
K. Mimasu, V. Sanz and C. Williams, Higher order QCD predictions for Associated Higgs production with anomalous couplings to gauge bosons, JHEP 08 (2016) 039 [arXiv:1512.02572] [INSPIRE].
C. Degrande et al., Electroweak Higgs boson production in the standard model effective field theory beyond leading order in QCD, Eur. Phys. J. C 77 (2017) 262 [arXiv:1609.04833] [INSPIRE].
C. Degrande et al., Probing top-Higgs non-standard interactions at the LHC, JHEP 07 (2012) 036 [Erratum ibid. 03 (2013) 032] [arXiv:1205.1065] [INSPIRE].
M. Schulze and Y. Soreq, Pinning down electroweak dipole operators of the top quark, Eur. Phys. J. C 76 (2016) 466 [arXiv:1603.08911] [INSPIRE].
F. Maltoni, K. Paul, T. Stelzer and S. Willenbrock, Associated production of Higgs and single top at hadron colliders, Phys. Rev. D 64 (2001) 094023 [hep-ph/0106293] [INSPIRE].
S. Biswas, E. Gabrielli and B. Mele, Single top and Higgs associated production as a probe of the Htt coupling sign at the LHC, JHEP 01 (2013) 088 [arXiv:1211.0499] [INSPIRE].
M. Farina et al., Lifting degeneracies in Higgs couplings using single top production in association with a Higgs boson, JHEP 05 (2013) 022 [arXiv:1211.3736] [INSPIRE].
F. Demartin, F. Maltoni, K. Mawatari and M. Zaro, Higgs production in association with a single top quark at the LHC, Eur. Phys. J. C 75 (2015) 267 [arXiv:1504.00611] [INSPIRE].
ATLAS collaboration, 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, Phys. Lett. B 780 (2018) 557 [arXiv:1710.03659] [INSPIRE].
CMS collaboration, Evidence for the standard model production of a Z boson with a single top quark in pp collisions at \( \sqrt{s}=13 \) TeV, CMS-PAS-TOP-16-020 (2016).
CMS collaboration, Measurement of the associated production of a single top quark and a Z boson in pp collisions at \( \sqrt{s}=13 \) TeV, Phys. Lett. B 779 (2018) 358 [arXiv:1712.02825] [INSPIRE].
CMS collaboration, Search for the associated production of a Higgs boson with a single top quark in proton-proton collisions at \( \sqrt{s}=8 \) TeV, JHEP 06 (2016) 177 [arXiv:1509.08159] [INSPIRE].
CMS collaboration, Search for \( H\to b\overline{b} \) in association with a single top quark as a test of Higgs boson couplings at 13 TeV, CMS-PAS-HIG-16-019 (2016).
CMS collaboration, Search for production of a Higgs boson and a single top quark in multilepton final states in proton collisions at \( \sqrt{s}=13 \) TeV, CMS-PAS-HIG-17-005 (2017).
J. Campbell, R.K. Ellis and R. Röntsch, Single top production in association with a Z boson at the LHC, Phys. Rev. D 87 (2013) 114006 [arXiv:1302.3856] [INSPIRE].
J. Alwall et al., The automated computation of tree-level and next-to-leading order differential cross sections and their matching to parton shower simulations, JHEP 07 (2014) 079 [arXiv:1405.0301] [INSPIRE].
C. Zhang, Automating predictions for standard model effective field theory in MadGraph5_aMC@NLONLO predictions for effective field theory with MadGraph5 aMC@NLO, PoS RADCOR2015 (2016) 101 [arXiv:1601.03994] [INSPIRE].
B. Grzadkowski, M. Iskrzynski, M. Misiak and J. Rosiek, Dimension-six terms in the standard model lagrangian, JHEP 10 (2010) 085 [arXiv:1008.4884] [INSPIRE].
G. D’Ambrosio, G.F. Giudice, G. Isidori and A. Strumia, Minimal flavor violation: an effective field theory approach, Nucl. Phys. B 645 (2002) 155 [hep-ph/0207036] [INSPIRE].
D. Barducci et al., Interpreting top-quark LHC measurements in the standard-model effective field theory, arXiv:1802.07237 [INSPIRE].
G. Durieux, F. Maltoni and C. Zhang, Global approach to top-quark flavor-changing interactions, Phys. Rev. D 91 (2015) 074017 [arXiv:1412.7166] [INSPIRE].
Z. Han and W. Skiba, Effective theory analysis of precision electroweak data, Phys. Rev. D 71 (2005) 075009 [hep-ph/0412166] [INSPIRE].
A. Falkowski and F. Riva, Model-independent precision constraints on dimension-6 operators, JHEP 02 (2015) 039 [arXiv:1411.0669] [INSPIRE].
C. Grojean, W. Skiba and J. Terning, Disguising the oblique parameters, Phys. Rev. D 73 (2006) 075008 [hep-ph/0602154] [INSPIRE].
R. Alonso, E.E. Jenkins, A.V. Manohar and M. Trott, Renormalization group evolution of the standard model dimension six operators III: gauge coupling dependence and phenomenology, JHEP 04 (2014) 159 [arXiv:1312.2014] [INSPIRE].
I. Brivio and M. Trott, Scheming in the SMEFT. . . and a reparameterization invariance!, JHEP 07 (2017) 148 [arXiv:1701.06424] [INSPIRE].
K. Hagiwara, S. Ishihara, R. Szalapski and D. Zeppenfeld, Low-energy effects of new interactions in the electroweak boson sector, Phys. Rev. D 48 (1993) 2182 [INSPIRE].
C. Degrande et al., Effective field theory: a modern approach to anomalous couplings, Annals Phys. 335 (2013) 21 [arXiv:1205.4231] [INSPIRE].
E.E. Jenkins, A.V. Manohar and M. Trott, Renormalization group evolution of the standard model dimension six operators I: formalism and Λ dependence, JHEP 10 (2013) 087 [arXiv:1308.2627] [INSPIRE].
E.E. Jenkins, A.V. Manohar and M. Trott, Renormalization group evolution of the standard model dimension six operators II: Yukawa dependence, JHEP 01 (2014) 035 [arXiv:1310.4838] [INSPIRE].
T. Corbett, O.J.P. Éboli, J. Gonzalez-Fraile and M.C. Gonzalez-Garcia, Determining triple gauge boson couplings from Higgs data, Phys. Rev. Lett. 111 (2013) 011801 [arXiv:1304.1151] [INSPIRE].
A. Falkowski, M. Gonzalez-Alonso, A. Greljo and D. Marzocca, Global constraints on anomalous triple gauge couplings in effective field theory approach, Phys. Rev. Lett. 116 (2016) 011801 [arXiv:1508.00581] [INSPIRE].
G. Bordes and B. van Eijk, On the associate production of a neutral intermediate mass Higgs boson with a single top quark at the LHC and SSC, Phys. Lett. B 299 (1993) 315 [INSPIRE].
S. Dawson, The effective W approximation, Nucl. Phys. B 249 (1985) 42 [INSPIRE].
Z. Kunszt and D.E. Soper, On the validity of the effective W approximation, Nucl. Phys. B 296 (1988) 253 [INSPIRE].
P. Borel, R. Franceschini, R. Rattazzi and A. Wulzer, Probing the scattering of equivalent electroweak bosons, JHEP 06 (2012) 122 [arXiv:1202.1904] [INSPIRE].
J.A. Dror, M. Farina, E. Salvioni and J. Serra, Strong tW scattering at the LHC, JHEP 01 (2016) 071 [arXiv:1511.03674] [INSPIRE].
T. Corbett, O.J.P. Éboli and M.C. Gonzalez-Garcia, Unitarity constraints on dimension-six operators, Phys. Rev. D 91 (2015) 035014 [arXiv:1411.5026] [INSPIRE].
T. Corbett, O.J.P. Éboli and M.C. Gonzalez-Garcia, Unitarity constraints on dimension-six operators II: including fermionic operators, Phys. Rev. D 96 (2017) 035006 [arXiv:1705.09294] [INSPIRE].
A. Buckley et al., Constraining top quark effective theory in the LHC Run II era, JHEP 04 (2016) 015 [arXiv:1512.03360] [INSPIRE].
S. Alioli et al., Right-handed charged currents in the era of the Large Hadron Collider, JHEP 05 (2017) 086 [arXiv:1703.04751] [INSPIRE].
A. Butter et al., The gauge-Higgs legacy of the LHC Run I, JHEP 07 (2016) 152 [arXiv:1604.03105] [INSPIRE].
CMS collaboration, Search for the associated production of a Higgs boson with a top quark pair in final states with a τ lepton at \( \sqrt{s}=13 \) TeV, CMS-PAS-HIG-17-003 (2017).
CMS collaboration, Search for Higgs boson production in association with top quarks in multilepton final states at \( \sqrt{s}=13 \) TeV, CMS-PAS-HIG-17-004 (2017).
ATLAS collaboration, Evidence for the associated production of the Higgs boson and a top quark pair with the ATLAS detector, Phys. Rev. D 97 (2018) 072003 [arXiv:1712.08891] [INSPIRE].
ATLAS collaboration, Search for the standard model Higgs boson produced in association with top quarks and decaying into a bb pair in pp collisions at \( \sqrt{s}=13 \) YeV with the ATLAS detector, Phys. Rev. D 97 (2018) 072016 [arXiv:1712.08895] [INSPIRE].
C. Zhang, Constraining qqtt operators from four-top production: a case for enhanced EFT sensitivity, Chin. Phys. C 42 (2018) 023104 [arXiv:1708.05928] [INSPIRE].
CMS collaboration, Measurement of the single-top-quark t-channel cross section in pp collisions at \( \sqrt{s}=7 \) TeV, JHEP 12 (2012) 035 [arXiv:1209.4533] [INSPIRE].
CMS collaboration, Measurement of the t-channel single-top-quark production cross section and of the |V tb| CKM matrix element in pp collisions at \( \sqrt{s}=8 \) TeV, JHEP 06 (2014) 090 [arXiv:1403.7366] [INSPIRE].
ATLAS collaboration, Comprehensive measurements of t-channel single top-quark production cross sections at \( \sqrt{s}=7 \) TeV with the ATLAS detector, Phys. Rev. D 90 (2014) 112006 [arXiv:1406.7844] [INSPIRE].
ATLAS collaboration, Evidence for single top-quark production in the s-channel in proton-proton collisions at \( \sqrt{s}=8 \) TeV with the ATLAS detector using the Matrix Element Method, Phys. Lett. B 756 (2016) 228 [arXiv:1511.05980] [INSPIRE].
CMS collaboration, Search for s channel single top quark production in pp collisions at \( \sqrt{s}=7 \) and 8 TeV, JHEP 09 (2016) 027 [arXiv:1603.02555] [INSPIRE].
ATLAS collaboration, Measurement of the inclusive cross-sections of single top-quark and top-antiquark t-channel production in pp collisions at \( \sqrt{s}=13 \) TeV with the ATLAS detector, JHEP 04 (2017) 086 [arXiv:1609.03920] [INSPIRE].
CMS collaboration, Cross section measurement of t-channel single top quark production in pp collisions at \( \sqrt{s}=13 \) TeV, Phys. Lett. B 772 (2017) 752 [arXiv:1610.00678] [INSPIRE].
ATLAS collaboration, Fiducial, total and differential cross-section measurements of t-channel single top-quark production in pp collisions at 8 TeV using data collected by the ATLAS detector, Eur. Phys. J. C 77 (2017) 531 [arXiv:1702.02859] [INSPIRE].
C. Zhang, N. Greiner and S. Willenbrock, Constraints on non-standard top quark couplings, Phys. Rev. D 86 (2012) 014024 [arXiv:1201.6670] [INSPIRE].
A. Alloul et al., FeynRules 2.0 — A complete toolbox for tree-level phenomenology, Comput. Phys. Commun. 185 (2014) 2250 [arXiv:1310.1921] [INSPIRE].
P. de Aquino et al., ALOHA: Automatic Libraries Of Helicity Amplitudes for Feynman Diagram Computations, Comput. Phys. Commun. 183 (2012) 2254 [arXiv:1108.2041] [INSPIRE].
C. Degrande et al., UFO — The Universal FeynRules Output, Comput. Phys. Commun. 183 (2012) 1201 [arXiv:1108.2040] [INSPIRE].
C. Degrande, Automatic evaluation of UV and R2 terms for beyond the Standard Model Lagrangians: a proof-of-principle, Comput. Phys. Commun. 197 (2015) 239 [arXiv:1406.3030] [INSPIRE].
V. Hirschi et al., Automation of one-loop QCD corrections, JHEP 05 (2011) 044 [arXiv:1103.0621] [INSPIRE].
R. Frederix, S. Frixione, F. Maltoni and T. Stelzer, Automation of next-to-leading order computations in QCD: The FKS subtraction, JHEP 10 (2009) 003 [arXiv:0908.4272] [INSPIRE].
NNPDF collaboration, R.D. Ball et al., Parton distributions for the LHC Run II, JHEP 04 (2015) 040 [arXiv:1410.8849] [INSPIRE].
CMS collaboration, Search for production of a Higgs boson and a single top quark in multilepton final states in proton collisions at \( \sqrt{s}=13 \) TeV, CMS-PAS-HIG-17-005 (2017).
J. Chang, K. Cheung, J.S. Lee and C.-T. Lu, Probing the top-Yukawa coupling in associated Higgs production with a single top quark, JHEP 05 (2014) 062 [arXiv:1403.2053] [INSPIRE].
Open Access
This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.
Author information
Authors and Affiliations
Corresponding author
Additional information
ArXiv ePrint: 1804.07773
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made.
The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.
To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/.
About this article
Cite this article
Degrande, C., Maltoni, F., Mimasu, K. et al. Single-top associated production with a Z or H boson at the LHC: the SMEFT interpretation. J. High Energ. Phys. 2018, 5 (2018). https://doi.org/10.1007/JHEP10(2018)005
Received:
Revised:
Accepted:
Published:
DOI: https://doi.org/10.1007/JHEP10(2018)005