Abstract
We report on the calculation of the next-to-leading order QCD corrections to the production of a \( t\overline{t} \) pair in association with two heavy-flavour jets. We concentrate on the di-lepton \( t\overline{t} \) decay channel at the LHC with \( \sqrt{s} \) = 13 TeV. The computation is based on pp → e+νeμ−\( \overline{\nu} \)μ\( b\overline{b}b\overline{b} \) matrix elements and includes all resonant and non-resonant diagrams, interferences and off-shell effects of the top quark and the W gauge boson. As it is customary for such studies, results are presented in the form of inclusive and differential fiducial cross sections. We extensively investigate the dependence of our results upon variation of renormalisation and factorisation scales and parton distribution functions in the quest for an accurate estimate of the theoretical uncertainties. We additionally study the impact of the contributions induced by the bottom-quark parton density. Results presented here are particularly relevant for measurements of \( t\overline{t}H \)(H → \( b\overline{b} \)) and the determination of the Higgs coupling to the top quark. In addition, they might be used for precise measurements of the top-quark fiducial cross sections and to investigate top-quark decay modelling at the LHC.
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References
CMS collaboration, Observation of \( t\overline{t}H \) production, Phys. Rev. Lett. 120 (2018) 231801 [arXiv:1804.02610] [INSPIRE].
ATLAS collaboration, Observation of Higgs boson production in association with a top quark pair at the LHC with the ATLAS detector, Phys. Lett. B 784 (2018) 173 [arXiv:1806.00425] [INSPIRE].
LHC Higgs Cross Section Working Group collaboration, Handbook of LHC Higgs Cross Sections: 4. Deciphering the Nature of the Higgs Sector, arXiv:1610.07922 [INSPIRE].
CMS collaboration, Search for \( t\overline{t}H \) production in the H → \( b\overline{b} \) decay channel with leptonic \( t\overline{t} \) decays in proton-proton collisions at \( \sqrt{s} \) = 13 TeV, JHEP 03 (2019) 026 [arXiv:1804.03682] [INSPIRE].
ATLAS collaboration, Search for the standard model Higgs boson produced in association with top quarks and decaying into a \( b\overline{b} \) pair in pp collisions at \( \sqrt{s} \) = 13 TeV with the ATLAS detector, Phys. Rev. D 97 (2018) 072016 [arXiv:1712.08895] [INSPIRE].
R.V. Harlander, S.Y. Klein and M. Lipp, FeynGame, Comput. Phys. Commun. 256 (2020) 107465 [arXiv:2003.00896] [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].
ATLAS collaboration, Search for four-top-quark production in the single-lepton and opposite-sign dilepton final states in pp collisions at \( \sqrt{s} \) = 13 TeV with the ATLAS detector, Phys. Rev. D 99 (2019) 052009 [arXiv:1811.02305] [INSPIRE].
CMS collaboration, Search for standard model production of four top quarks in proton-proton collisions at \( \sqrt{s} \) = 13 TeV, Phys. Lett. B 772 (2017) 336 [arXiv:1702.06164] [INSPIRE].
A. Bredenstein, A. Denner, S. Dittmaier and S. Pozzorini, NLO QCD corrections to \( t\overline{t}b\overline{b} \) production at the LHC: 1. Quark-antiquark annihilation, JHEP 08 (2008) 108 [arXiv:0807.1248] [INSPIRE].
A. Bredenstein, A. Denner, S. Dittmaier and S. Pozzorini, NLO QCD corrections to pp → \( t\overline{t}b\overline{b} \) + X at the LHC, Phys. Rev. Lett. 103 (2009) 012002 [arXiv:0905.0110] [INSPIRE].
G. Bevilacqua, M. Czakon, C.G. Papadopoulos, R. Pittau and M. Worek, Assault on the NLO Wishlist: pp → \( t\overline{t}b\overline{b} \), JHEP 09 (2009) 109 [arXiv:0907.4723] [INSPIRE].
A. Bredenstein, A. Denner, S. Dittmaier and S. Pozzorini, NLO QCD Corrections to Top Anti-Top Bottom Anti-Bottom Production at the LHC: 2. full hadronic results, JHEP 03 (2010) 021 [arXiv:1001.4006] [INSPIRE].
M. Worek, On the next-to-leading order QCD K-factor for top \( t\overline{t}b\overline{b} \) production at the Tevatron, JHEP 02 (2012) 043 [arXiv:1112.4325] [INSPIRE].
G. Bevilacqua and M. Worek, On the ratio of \( t\overline{t}b\overline{b} \) and \( t\overline{t} jj \) cross sections at the CERN Large Hadron Collider, JHEP 07 (2014) 135 [arXiv:1403.2046] [INSPIRE].
F. Buccioni, S. Kallweit, S. Pozzorini and M.F. Zoller, NLO QCD predictions for \( t\overline{t}b\overline{b} \) production in association with a light jet at the LHC, JHEP 12 (2019) 015 [arXiv:1907.13624] [INSPIRE].
A. Kardos and Z. Trócsányi, Hadroproduction of \( t\overline{t} \) pair with a \( b\overline{b} \) pair using PowHel, J. Phys. G 41 (2014) 075005 [arXiv:1303.6291] [INSPIRE].
F. Cascioli, P. Maierhöfer, N. Moretti, S. Pozzorini and F. Siegert, NLO matching for \( t\overline{t}b\overline{b} \) production with massive b-quarks, Phys. Lett. B 734 (2014) 210 [arXiv:1309.5912] [INSPIRE].
M.V. Garzelli, A. Kardos and Z. Trócsányi, Hadroproduction of \( t\overline{t}b\overline{b} \) final states at LHC: predictions at NLO accuracy matched with Parton Shower, JHEP 03 (2015) 083 [arXiv:1408.0266] [INSPIRE].
G. Bevilacqua, M.V. Garzelli and A. Kardos, \( t\overline{t}b\overline{b} \) hadroproduction with massive bottom quarks with PowHel, arXiv:1709.06915 [INSPIRE].
T. Ježo, J.M. Lindert, N. Moretti and S. Pozzorini, New NLOPS predictions for \( t\overline{t} \) + b-jet production at the LHC, Eur. Phys. J. C 78 (2018) 502 [arXiv:1802.00426] [INSPIRE].
CMS collaboration, Measurements of \( t\overline{t} \) cross sections in association with b jets and inclusive jets and their ratio using dilepton final states in pp collisions at \( \sqrt{s} \) = 13 TeV, Phys. Lett. B 776 (2018) 355 [arXiv:1705.10141] [INSPIRE].
ATLAS collaboration, Measurements of inclusive and differential fiducial cross-sections of \( t\overline{t} \) production with additional heavy-flavour jets in proton-proton collisions at \( \sqrt{s} \) = 13 TeV with the ATLAS detector, JHEP 04 (2019) 046 [arXiv:1811.12113] [INSPIRE].
CMS collaboration, Measurement of the cross section for \( t\overline{t} \) production with additional jets and b jets in pp collisions at \( \sqrt{s} \) = 13 TeV, JHEP 07 (2020) 125 [arXiv:2003.06467] [INSPIRE].
A. Denner, J.-N. Lang and M. Pellen, Full NLO QCD corrections to off-shell ttbb production, arXiv:2008.00918 [INSPIRE].
G. Bevilacqua et al., HELAC-NLO, Comput. Phys. Commun. 184 (2013) 986 [arXiv:1110.1499] [INSPIRE].
G. Bevilacqua, H.B. Hartanto, M. Kraus and M. Worek, Top Quark Pair Production in Association with a Jet with Next-to-Leading-Order QCD Off-Shell Effects at the Large Hadron Collider, Phys. Rev. Lett. 116 (2016) 052003 [arXiv:1509.09242] [INSPIRE].
G. Bevilacqua, H.B. Hartanto, M. Kraus and M. Worek, Off-shell Top Quarks with One Jet at the LHC: A comprehensive analysis at NLO QCD, JHEP 11 (2016) 098 [arXiv:1609.01659] [INSPIRE].
G. Bevilacqua, H.B. Hartanto, M. Kraus, T. Weber and M. Worek, Hard Photons in Hadroproduction of Top Quarks with Realistic Final States, JHEP 10 (2018) 158 [arXiv:1803.09916] [INSPIRE].
G. Bevilacqua, H.B. Hartanto, M. Kraus, T. Weber and M. Worek, Towards constraining Dark Matter at the LHC: Higher order QCD predictions for \( t\overline{t} \) + Z(Z → νℓνℓ), JHEP 11 (2019) 001 [arXiv:1907.09359] [INSPIRE].
G. Bevilacqua, H.-Y. Bi, H.B. Hartanto, M. Kraus and M. Worek, The simplest of them all: \( t\overline{t}{W}^{\pm } \) at NLO accuracy in QCD, JHEP 08 (2020) 043 [arXiv:2005.09427] [INSPIRE].
M. Czakon, C.G. Papadopoulos and M. Worek, Polarizing the Dipoles, JHEP 08 (2009) 085 [arXiv:0905.0883] [INSPIRE].
A. van Hameren, PARNI for importance sampling and density estimation, Acta Phys. Polon. B 40 (2009) 259 [arXiv:0710.2448] [INSPIRE].
A. van Hameren, Kaleu: A General-Purpose Parton-Level Phase Space Generator, arXiv:1003.4953 [INSPIRE].
A. Denner, S. Dittmaier, M. Roth and D. Wackeroth, Predictions for all processes e+e− → 4 fermions + γ, Nucl. Phys. B 560 (1999) 33 [hep-ph/9904472] [INSPIRE].
A. Denner, S. Dittmaier, M. Roth and L.H. Wieders, Electroweak corrections to charged-current e+e− → 4 fermion processes: Technical details and further results, Nucl. Phys. B 724 (2005) 247 [Erratum ibid. 854 (2012) 504] [hep-ph/0505042] [INSPIRE].
G. Bevilacqua, M. Czakon, A. van Hameren, C.G. Papadopoulos and M. Worek, Complete off-shell effects in top quark pair hadroproduction with leptonic decay at next-to-leading order, JHEP 02 (2011) 083 [arXiv:1012.4230] [INSPIRE].
A. Denner, S. Dittmaier, S. Kallweit and S. Pozzorini, NLO QCD corrections to off-shell top-antitop production with leptonic decays at hadron colliders, JHEP 10 (2012) 110 [arXiv:1207.5018] [INSPIRE].
A. van Hameren, C.G. Papadopoulos and R. Pittau, Automated one-loop calculations: A Proof of concept, JHEP 09 (2009) 106 [arXiv:0903.4665] [INSPIRE].
G. Ossola, C.G. Papadopoulos and R. Pittau, CutTools: A Program implementing the OPP reduction method to compute one-loop amplitudes, JHEP 03 (2008) 042 [arXiv:0711.3596] [INSPIRE].
G. Ossola, C.G. Papadopoulos and R. Pittau, Reducing full one-loop amplitudes to scalar integrals at the integrand level, Nucl. Phys. B 763 (2007) 147 [hep-ph/0609007] [INSPIRE].
P. Nogueira, Automatic Feynman graph generation, J. Comput. Phys. 105 (1993) 279.
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].
A. van Hameren, OneLOop: For the evaluation of one-loop scalar functions, Comput. Phys. Commun. 182 (2011) 2427 [arXiv:1007.4716] [INSPIRE].
S. Badger, B. Biedermann and P. Uwer, NGluon: A Package to Calculate One-loop Multi-gluon Amplitudes, Comput. Phys. Commun. 182 (2011) 1674 [arXiv:1011.2900] [INSPIRE].
S. Catani and M.H. Seymour, A General algorithm for calculating jet cross-sections in NLO QCD, Nucl. Phys. B 485 (1997) 291 [Erratum ibid. 510 (1998) 503] [hep-ph/9605323] [INSPIRE].
S. Catani, S. Dittmaier, M.H. Seymour and Z. Trócsányi, The Dipole formalism for next-to-leading order QCD calculations with massive partons, Nucl. Phys. B 627 (2002) 189 [hep-ph/0201036] [INSPIRE].
G. Bevilacqua, M. Czakon, M. Kubocz and M. Worek, Complete Nagy-Soper subtraction for next-to-leading order calculations in QCD, JHEP 10 (2013) 204 [arXiv:1308.5605] [INSPIRE].
Z. Nagy and Z. Trócsányi, Next-to-leading order calculation of four jet observables in electron positron annihilation, Phys. Rev. D 59 (1999) 014020 [Erratum ibid. 62 (2000) 099902] [hep-ph/9806317] [INSPIRE].
Z. Nagy, Next-to-leading order calculation of three jet observables in hadron hadron collision, Phys. Rev. D 68 (2003) 094002 [hep-ph/0307268] [INSPIRE].
M. Czakon, H.B. Hartanto, M. Kraus and M. Worek, Matching the Nagy-Soper parton shower at next-to-leading order, JHEP 06 (2015) 033 [arXiv:1502.00925] [INSPIRE].
J. Alwall et al., A Standard format for Les Houches event files, Comput. Phys. Commun. 176 (2007) 300 [hep-ph/0609017] [INSPIRE].
I. Antcheva et al., ROOT: A C++ framework for petabyte data storage, statistical analysis and visualization, Comput. Phys. Commun. 180 (2009) 2499 [arXiv:1508.07749] [INSPIRE].
Z. Bern et al., Ntuples for NLO Events at Hadron Colliders, Comput. Phys. Commun. 185 (2014) 1443 [arXiv:1310.7439] [INSPIRE].
NNPDF collaboration, Parton distributions from high-precision collider data, Eur. Phys. J. C 77 (2017) 663 [arXiv:1706.00428] [INSPIRE].
T.-J. Hou et al., New CTEQ global analysis of quantum chromodynamics with high-precision data from the LHC, Phys. Rev. D 103 (2021) 014013 [arXiv:1912.10053] [INSPIRE].
L.A. Harland-Lang, A.D. Martin, P. Motylinski and R.S. Thorne, Parton distributions in the LHC era: MMHT 2014 PDFs, Eur. Phys. J. C 75 (2015) 204 [arXiv:1412.3989] [INSPIRE].
A. Buckley et al., LHAPDF6: parton density access in the LHC precision era, Eur. Phys. J. C 75 (2015) 132 [arXiv:1412.7420] [INSPIRE].
M. Jezabek and J.H. Kühn, QCD Corrections to Semileptonic Decays of Heavy Quarks, Nucl. Phys. B 314 (1989) 1 [INSPIRE].
L. Basso, S. Dittmaier, A. Huss and L. Oggero, Techniques for the treatment of IR divergences in decay processes at NLO and application to the top-quark decay, Eur. Phys. J. C 76 (2016) 56 [arXiv:1507.04676] [INSPIRE].
M. Cacciari, G.P. Salam and G. Soyez, The anti-kt jet clustering algorithm, JHEP 04 (2008) 063 [arXiv:0802.1189] [INSPIRE].
S. Dulat et al., New parton distribution functions from a global analysis of quantum chromodynamics, Phys. Rev. D 93 (2016) 033006 [arXiv:1506.07443] [INSPIRE].
Particle Data Group collaboration, Review of Particle Physics, PTEP 2020 (2020) 083C01 [INSPIRE].
J. Butterworth et al., PDF4LHC recommendations for LHC Run II, J. Phys. G 43 (2016) 023001 [arXiv:1510.03865] [INSPIRE].
A. Banfi, G.P. Salam and G. Zanderighi, Infrared safe definition of jet flavor, Eur. Phys. J. C 47 (2006) 113 [hep-ph/0601139] [INSPIRE].
A. Buckley and C. Pollard, QCD-aware partonic jet clustering for truth-jet flavour labelling, Eur. Phys. J. C 76 (2016) 71 [arXiv:1507.00508] [INSPIRE].
D. Krohn, M.D. Schwartz, T. Lin and W.J. Waalewijn, Jet Charge at the LHC, Phys. Rev. Lett. 110 (2013) 212001 [arXiv:1209.2421] [INSPIRE].
A new tagger for the charge identification of b-jets, CERN, Geneva (2015) ATL-PHYS-PUB-2015-040.
ATLAS and CMS collaborations collaboration, Jet charge determination at the LHC, CERN, Geneva (2017) ATL-PHYS-PROC-2017-017.
ATLAS collaboration, Measurement of the Jet Vertex Charge algorithm performance for identified b-jets in \( t\overline{t} \) events in pp collisions with the ATLAS detector, CERN, Geneva (2018) ATLAS-CONF-2018-022.
S. Alekhin, J. Blümlein and S. Moch, NLO PDFs from the ABMP16 fit, Eur. Phys. J. C 78 (2018) 477 [arXiv:1803.07537] [INSPIRE].
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Bevilacqua, G., Bi, HY., Hartanto, H.B. et al. \( t\overline{t}b\overline{b} \) at the LHC: on the size of corrections and b-jet definitions. J. High Energ. Phys. 2021, 8 (2021). https://doi.org/10.1007/JHEP08(2021)008
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DOI: https://doi.org/10.1007/JHEP08(2021)008