Abstract
In the presence of CP violation, the Higgs-top coupling may have both scalar and pseudoscalar components, κ t and \( {{\widetilde{\kappa}}_t} \), which are bounded indirectly but only weakly by the present experimental constraints on the Higgs-gluon-gluon and Higgs-γ-γ couplings, whereas upper limits on electric dipole moments provide strong additional indirect constraints on \( {{\widetilde{\kappa}}_t} \), if the Higgs-electron coupling is similar to that in the Standard Model and there are no cancellations with other contributions. We discuss methods to measure directly the scalar and pseudoscalar Higgs-top couplings by measurements of Higgs production in association with \( \overline{t}t \), single t and single \( \overline{t} \) at the LHC. Measurements of the total cross sections are very sensitive to variations in the Higgs-top couplings that are consistent with the present indirect constraints, as are invariant mass distributions in \( \overline{t}tH \), tH and \( \overline{t}H \) final states. We also investigate the additional information on κ t and \( {{\widetilde{\kappa}}_t} \) that could be obtained from measurements of the longitudinal and transverse t polarization in the different associated production channels, and the \( \overline{t}t \) spin correlation in \( \overline{t}tH \) events.
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References
ATLAS collaboration, Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC, Phys. Lett. B 716 (2012) 1 [arXiv:1207.7214] [INSPIRE].
CMS collaboration, Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC, Phys. Lett. B 716 (2012) 30 [arXiv:1207.7235] [INSPIRE].
ATLAS collaboration, Study of the spin of the Higgs-like boson in the two photon decay channel using 20.7 fb −1 of pp collisions collected at \( \sqrt{s} \) = 8 TeV with the ATLAS detector, ATLAS-CONF-2013-029 (2013).
ATLAS collaboration, Study of the spin properties of the Higgs-like particle in the H → WW (∗) → eνμν channel with 21 fb −1 of \( \sqrt{s} \) = 8 TeV data collected with the ATLAS detector, ATLAS-CONF-2013-031 (2013).
ATLAS collaboration, Measurements of the properties of the Higgs-like boson in the four lepton decay channel with the ATLAS detector using 25 fb −1 of proton-proton collision data, ATLAS-CONF-2013-013 (2013).
CMS collaboration, Study of the Mass and Spin-Parity of the Higgs Boson Candidate Via Its Decays to Z Boson Pairs, Phys. Rev. Lett. 110 (2013) 081803 [arXiv:1212.6639] [INSPIRE].
S. Bolognesi et al., On the spin and parity of a single-produced resonance at the LHC, Phys. Rev. D 86 (2012) 095031 [arXiv:1208.4018] [INSPIRE].
A. Freitas and P. Schwaller, Higgs CP Properties From Early LHC Data, Phys. Rev. D 87 (2013) 055014 [arXiv:1211.1980] [INSPIRE].
J. Ellis and D.S. Hwang, Does the ‘Higgs’ have Spin Zero?, JHEP 09 (2012) 071 [arXiv:1202.6660] [INSPIRE].
J. Ellis, R. Fok, D.S. Hwang, V. Sanz and T. You, Distinguishing ’Higgs’ spin hypotheses using γγ and W W ∗ decays, Eur. Phys. J. C 73 (2013) 2488 [arXiv:1210.5229] [INSPIRE].
J. Ellis, V. Sanz and T. You, Prima Facie Evidence against Spin-Two Higgs Impostors, Phys. Lett. B 726 (2013) 244 [arXiv:1211.3068] [INSPIRE].
ATLAS collaboration, Study of the spin of the new boson with up to 25 fb −1 of ATLAS data, ATLAS-CONF-2013-040 (2013).
J. Ellis, D.S. Hwang, V. Sanz and T. You, A Fast Track towards the ‘Higgs’ Spin and Parity, JHEP 11 (2012) 134 [arXiv:1208.6002] [INSPIRE].
D0 collaboration, http://www-d0.fnal.gov/Run2Physics/WWW/results/prelim/HIGGS/H138/H138.pdf, http://www-d0.fnal.gov/Run2Physics/WWW/results/prelim/HIGGS/H139/H139.pdf.
J. Ellis, V. Sanz and T. You, Associated Production Evidence against Higgs Impostors and Anomalous Couplings, Eur. Phys. J. C 73 (2013) 2507 [arXiv:1303.0208] [INSPIRE].
R.M. Godbole, D. Miller and M.M. Muhlleitner, Aspects of CP-violation in the H ZZ coupling at the LHC, JHEP 12 (2007) 031 [arXiv:0708.0458] [INSPIRE].
Y. Gao et al., Spin determination of single-produced resonances at hadron colliders, Phys. Rev. D 81 (2010) 075022 [arXiv:1001.3396] [INSPIRE].
B. Coleppa, K. Kumar and H.E. Logan, Can the 126 GeV boson be a pseudoscalar?, Phys. Rev. D 86 (2012) 075022 [arXiv:1208.2692] [INSPIRE].
A. Djouadi and G. Moreau, The couplings of the Higgs boson and its CP properties from fits of the signal strengths and their ratios at the 7 + 8 TeV LHC, arXiv:1303.6591 [INSPIRE].
D. Stolarski and R. Vega-Morales, Directly Measuring the Tensor Structure of the Scalar Coupling to Gauge Bosons, Phys. Rev. D 86 (2012) 117504 [arXiv:1208.4840] [INSPIRE].
T. Plehn, D.L. Rainwater and D. Zeppenfeld, Determining the structure of Higgs couplings at the LHC, Phys. Rev. Lett. 88 (2002) 051801 [hep-ph/0105325] [INSPIRE].
S. Berge, W. Bernreuther, B. Niepelt and H. Spiesberger, How to pin down the CP quantum numbers of a Higgs boson in its tau decays at the LHC, Phys. Rev. D 84 (2011) 116003 [arXiv:1108.0670] [INSPIRE].
R. Harnik, A. Martin, T. Okui, R. Primulando and F. Yu, Measuring CP-violation in h → τ + τ − at Colliders,Phys. Rev. D 88 (2013) 076009 [arXiv:1308.1094][INSPIRE].
K. Hagiwara, Q. Li and K. Mawatari, Jet angular correlation in vector-boson fusion processes at hadron colliders, JHEP 07 (2009) 101 [arXiv:0905.4314] [INSPIRE].
C. Englert, M. Spannowsky and M. Takeuchi, Measuring Higgs CP and couplings with hadronic event shapes, JHEP 06 (2012) 108 [arXiv:1203.5788] [INSPIRE].
J.R. Andersen, C. Englert and M. Spannowsky, Extracting precise Higgs couplings by using the matrix element method, Phys. Rev. D 87 (2013) 015019 [arXiv:1211.3011] [INSPIRE].
C. Englert, D. Goncalves-Netto, K. Mawatari and T. Plehn, Higgs Quantum Numbers in Weak Boson Fusion, JHEP 01 (2013) 148 [arXiv:1212.0843] [INSPIRE].
C. Englert, D. Goncalves, G. Nail and M. Spannowsky, The shape of spins, Phys. Rev. D 88 (2013)013016 [arXiv:1304.0033] [INSPIRE].
V. Khoze, A. Martin and M. Ryskin, Hunting a light CP-violating Higgs via diffraction at the LHC, Eur. Phys. J. C 34 (2004) 327 [hep-ph/0401078] [INSPIRE].
J.R. Ellis, J.S. Lee and A. Pilaftsis, Diffraction as a CP and lineshape analyzer for MSSM Higgs bosons at the LHC, Phys. Rev. D 71 (2005) 075007 [hep-ph/0502251] [INSPIRE].
ECFA/DESY Photon Collider Working Group collaboration, B. Badelek et al., TESLA: The Superconducting electron positron linear collider with an integrated X-ray laser laboratory. Technical design report. Part 6. Appendices. Chapter 1. Photon collider at TESLA, Int. J. Mod. Phys. A 19 (2004) 5097 [hep-ex/0108012] [INSPIRE].
J. Brod, U. Haisch and J. Zupan, Constraints on CP-violating Higgs couplings to the third generation, JHEP 11 (2013) 180 [arXiv:1310.1385] [INSPIRE].
T. Plehn, G.P. Salam and M. Spannowsky, Fat Jets for a Light Higgs, Phys. Rev. Lett. 104 (2010) 111801 [arXiv:0910.5472] [INSPIRE].
P. Artoisenet, P. de Aquino, F. Maltoni and O. Mattelaer, Unravelling tth via the matrix element method, Phys. Rev. Lett. 111 (2013) 091802 [arXiv:1304.6414] [INSPIRE].
M.R. Buckley, T. Plehn, T. Schell and M. Takeuchi, Buckets of Higgs and Tops, JHEP 02 (2014) 130 [arXiv:1310.6034] [INSPIRE].
C. Boddy, S. Farrington and C. Hays, Higgs boson coupling sensitivity at the LHC using H → ττ decays, Phys. Rev. D 86 (2012) 073009 [arXiv:1208.0769][INSPIRE].
P. Agrawal, S. Bandyopadhyay and S.P. Das, Dilepton Signatures of the Higgs Boson with Tau-jet Tagging, arXiv:1308.6511 [INSPIRE].
F. Maltoni, D.L. Rainwater and S. Willenbrock, Measuring the top quark Yukawa coupling at hadron colliders via \( t\overline{t}H \) , H → W + W −, Phys. Rev. D 66 (2002) 034022 [hep-ph/0202205] [INSPIRE].
D. Curtin, J. Galloway and J.G. Wacker, Measuring the tth coupling from SSDL + 2b measurements, Phys. Rev. D 88 (2013) 093006 [arXiv:1306.5695] [INSPIRE].
P. Agrawal, S. Bandyopadhyay and S.P. Das, Multilepton Signatures of the Higgs Boson through its Production in Association with a Top-quark Pair, Phys. Rev. D 88 (2013) 093008 [arXiv:1308.3043] [INSPIRE].
ATLAS collaboration, Search for ttH production in the H → yy channel at \( \sqrt{s} \) = 8 TeV with the ATLAS detector, ATLAS-CONF-2013-080 (2013).
ATLAS collaboration, Search for the Standard Model Higgs boson produced in association with top quarks in proton-proton collisions at \( \sqrt{s} \) = 7 TeV using the ATLAS detector, ATLAS-CONF-2012-135 (2012).
CMS collaboration, Search for ttH production in events where H decays to photons at 8 TeV collisions, CMS-PAS-HIG-13-015 (2013).
CMS collaboration, Search for Higgs Boson Production in Association with a Top-Quark Pair and Decaying to Bottom Quarks or Tau Leptons, CMS-PAS-HIG-13-019 (2013).
CMS collaboration, Search for the standard model Higgs boson produced in association with top quarks in multilepton final states, CMS-PAS-HIG-13-020 (2013).
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].
P. Agrawal, S. Mitra and A. Shivaji, Effect of Anomalous Couplings on the Associated Production of a Single Top Quark and a Higgs Boson at the LHC, JHEP 12 (2013) 077 [arXiv:1211.4362] [INSPIRE].
S. Biswas, E. Gabrielli, F. Margaroli and B. Mele, Direct constraints on the top-Higgs coupling from the 8 TeV LHC data, JHEP 07 (2013) 073 [arXiv:1304.1822] [INSPIRE].
M. Farina, C. Grojean, F. Maltoni, E. Salvioni and A. Thamm, Lifting degeneracies in Higgs couplings using single top production in association with a Higgs boson, JHEP 05 (2013) 022 [arXiv:1211.3736] [INSPIRE].
K. Nishiwaki, S. Niyogi and A. Shivaji, ttH Anomalous Coupling in Double Higgs Production, arXiv:1309.6907 [INSPIRE].
M. Klute, R. Lafaye, T. Plehn, M. Rauch and D. Zerwas, Measuring Higgs Couplings at a Linear Collider, Europhys. Lett. 101 (2013) 51001 [arXiv:1301.1322] [INSPIRE].
J. Ellis and T. You, Updated Global Analysis of Higgs Couplings, JHEP 06 (2013) 103 [arXiv:1303.3879] [INSPIRE].
ACME collaboration, J. Baron et al., Order of Magnitude Smaller Limit on the Electric Dipole Moment of the Electron, Science 343 (2014) 269 [arXiv:1310.7534] [INSPIRE].
J. Alwall, M. Herquet, F. Maltoni, O. Mattelaer and T. Stelzer, MadGraph 5: going beyond, JHEP 06 (2011) 128 [arXiv:1106.0522] [INSPIRE].
M. Jezabek, Top quark physics, Nucl. Phys. Proc. Suppl. 37B (1994) 197 [hep-ph/9406411] [INSPIRE].
A. Brandenburg, Z. Si and P. Uwer, QCD corrected spin analyzing power of jets in decays of polarized top quarks, Phys. Lett. B 539 (2002) 235 [hep-ph/0205023] [INSPIRE].
R.M. Godbole, K. Rao, S.D. Rindani and R.K. Singh, On measurement of top polarization as a probe of \( t\overline{t} \) production mechanisms at the LHC, JHEP 11 (2010) 144 [arXiv:1010.1458] [INSPIRE].
M.R. Buckley, T. Plehn and M. Takeuchi, Buckets of tops, JHEP 08 (2013) 086 [arXiv:1302.6238] [INSPIRE].
A. Papaefstathiou and K. Sakurai, Determining the Helicity Structure of Third Generation Resonances, JHEP 06 (2012) 069 [arXiv:1112.3956] [INSPIRE].
ATLAS collaboration, Observation of spin correlation in \( t\overline{t} \) events from pp collisions at \( \sqrt{s} \) = 7 TeV using the ATLAS detector, Phys. Rev. Lett. 108 (2012) 212001 [arXiv:1203.4081] [INSPIRE].
CMS collaboration, Measurement of Spin Correlations in \( t\overline{t} \) production, CMS-PAS-TOP-12-004 (2012).
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Ellis, J., Hwang, D.S., Sakurai, K. et al. Disentangling Higgs-top couplings in associated production. J. High Energ. Phys. 2014, 4 (2014). https://doi.org/10.1007/JHEP04(2014)004
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DOI: https://doi.org/10.1007/JHEP04(2014)004