ATLAS reports an 8+ sigma excess in ttbar production near threshold, consistent with NRQCD quasi-bound states and measuring 9.3 pb.
NNLO corrections to top-pair production at hadron colliders: the all-fermionic scattering channels
7 Pith papers cite this work. Polarity classification is still indexing.
abstract
This is a second paper in our ongoing calculation of the next-to-next-to-leading order (NNLO) QCD correction to the total inclusive top-pair production cross-section at hadron colliders. In this paper we calculate the reaction $q\bar q \to t\bar t + q\bar q$ which was not considered in our previous work on $q\bar q \to t\bar t +X$ due to its phenomenologically negligible size. We also calculate all remaining fermion-pair-initiated partonic channels $qq', q\bar q'$ and $qq$ that contribute to top-pair production starting from NNLO. The contributions of these reactions to the total cross-section for top-pair production at the Tevatron and LHC are small, at the permil level. The most interesting feature of these reactions is their characteristic logarithmic rise in the high energy limit. We compute the constant term in the leading power behavior in this limit, and achieve precision that is an order of magnitude better than the precision of a recent theoretical prediction for this constant. All four partonic reactions computed in this paper are included in our numerical program Top++. The calculation of the NNLO corrections to the two remaining partonic reactions, $qg\to t\bar t+X$ and $gg\to t\bar t+X$, is ongoing.
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Top quark mass measured at 172.17 ± 1.56 GeV via unbinned maximum-likelihood fit to m(ℓ μ⁺μ⁻) in ATLAS Run 2 data using J/ψ decays.
NNLO QCD calculations using the MaunaKea code enhance c cbar and b bbar production cross sections by up to a factor of two over NLO predictions, reduce scale uncertainties, and match experimental data from 10 GeV to 14 TeV while suggesting PDF and mass constraints.
Differential cross sections for ttbar production in e+e-, mu+mu-, and e mu channels measured versus dineutrino pT and azimuthal separation using 138 fb-1 of 13 TeV CMS data, unfolded to particle level with unregularized least squares and found consistent with SM and MC predictions.
ATLAS reports the first measurement of the complete angular coefficients and pT-differential cross sections for W+ and W- bosons in full lepton phase space at 13 TeV, finding agreement with QCD predictions up to order α_S².
No evidence for charginos and neutralinos in R-parity violating Higgs-decay channels; masses 150-1100 GeV excluded at 95% CL assuming equal lepton branching fractions.
CMS reports fiducial and differential ttγ cross sections plus ttγ/tt ratios at 13 TeV that agree with Standard Model expectations within uncertainties.
citing papers explorer
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Observation of a cross-section enhancement near the $t\bar{t}$ production threshold in $\sqrt{s}=13$ TeV $pp$ collisions with the ATLAS detector
ATLAS reports an 8+ sigma excess in ttbar production near threshold, consistent with NRQCD quasi-bound states and measuring 9.3 pb.
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Measurement of the top-quark mass using decays with a $J/\psi$ meson at $\sqrt{s}=$13 TeV with the ATLAS detector
Top quark mass measured at 172.17 ± 1.56 GeV via unbinned maximum-likelihood fit to m(ℓ μ⁺μ⁻) in ATLAS Run 2 data using J/ψ decays.
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Inclusive charm and bottom quark pair production cross sections at hadron colliders at next-to-next-to-leading-order accuracy
NNLO QCD calculations using the MaunaKea code enhance c cbar and b bbar production cross sections by up to a factor of two over NLO predictions, reduce scale uncertainties, and match experimental data from 10 GeV to 14 TeV while suggesting PDF and mass constraints.
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Measurement of the dineutrino system kinematic variables in dileptonic top quark pair production in proton-proton collisions at$\sqrt{s}$ = 13 TeV
Differential cross sections for ttbar production in e+e-, mu+mu-, and e mu channels measured versus dineutrino pT and azimuthal separation using 138 fb-1 of 13 TeV CMS data, unfolded to particle level with unregularized least squares and found consistent with SM and MC predictions.
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Measurement of the $W$-boson angular coefficients and transverse momentum in $pp$ collisions at $\sqrt{s}=$ 13 TeV with the ATLAS detector
ATLAS reports the first measurement of the complete angular coefficients and pT-differential cross sections for W+ and W- bosons in full lepton phase space at 13 TeV, finding agreement with QCD predictions up to order α_S².
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Search for charginos and neutralinos with $B-L$ $R$-parity violating decays in $\sqrt{s}=13$ TeV and $13.6$ TeV $pp$ collisions with the ATLAS detector
No evidence for charginos and neutralinos in R-parity violating Higgs-decay channels; masses 150-1100 GeV excluded at 95% CL assuming equal lepton branching fractions.
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Inclusive and differential measurements of the $\mathrm{t\bar{t}}\gamma$ cross section and the $\mathrm{t\bar{t}}\gamma$ / $\mathrm{t\bar{t}}$ cross section ratio in proton-proton collisions at $\sqrt{s}$ = 13 TeV
CMS reports fiducial and differential ttγ cross sections plus ttγ/tt ratios at 13 TeV that agree with Standard Model expectations within uncertainties.