Normalized differential distributions of the $\Delta R (\gamma,\mathrm{tt})$. The nominal MC prediction used to compare the experimental results to is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and Madgraph5 at LO in QCD for photons from the decay part of the process. The alternative prediction is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and a POWHEG+Pythia $\mathrm{tt}$ simulation at NLO in QCD for photons from the decay part of the process.

Absolute differential distributions of the min. $\Delta R (\gamma,\mathrm{t})$. The nominal MC prediction used to compare the experimental results to is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and Madgraph5 at LO in QCD for photons from the decay part of the process. The alternative prediction is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and a POWHEG+Pythia $\mathrm{tt}$ simulation at NLO in QCD for photons from the decay part of the process.

Normalized differential distributions of the min. $\Delta R (\gamma,\mathrm{t})$. The nominal MC prediction used to compare the experimental results to is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and Madgraph5 at LO in QCD for photons from the decay part of the process. The alternative prediction is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and a POWHEG+Pythia $\mathrm{tt}$ simulation at NLO in QCD for photons from the decay part of the process.

Absolute differential distributions of the $m(\mathrm{tt})$. The nominal MC prediction used to compare the experimental results to is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and Madgraph5 at LO in QCD for photons from the decay part of the process. The alternative prediction is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and a POWHEG+Pythia $\mathrm{tt}$ simulation at NLO in QCD for photons from the decay part of the process.

Normalized differential distributions of the $m(\mathrm{tt})$. The nominal MC prediction used to compare the experimental results to is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and Madgraph5 at LO in QCD for photons from the decay part of the process. The alternative prediction is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and a POWHEG+Pythia $\mathrm{tt}$ simulation at NLO in QCD for photons from the decay part of the process.

Absolute differential distributions of the leading lepton $p_{\mathrm{T}}$. The nominal MC prediction used to compare the experimental results to is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and Madgraph5 at LO in QCD for photons from the decay part of the process. The alternative prediction is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and a POWHEG+Pythia $\mathrm{tt}$ simulation at NLO in QCD for photons from the decay part of the process. The theory predictions are computed at fixed order, at NLO in QCD, as described in Section 9.2 of the paper.

Normalized differential distributions of the leading lepton $p_{\mathrm{T}}$. The nominal MC prediction used to compare the experimental results to is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and Madgraph5 at LO in QCD for photons from the decay part of the process. The alternative prediction is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and a POWHEG+Pythia $\mathrm{tt}$ simulation at NLO in QCD for photons from the decay part of the process. The theory predictions are computed at fixed order, at NLO in QCD, as described in Section 9.2 of the paper.

Absolute differential distributions of the photon $p_{\mathrm{T}}$. The nominal MC prediction used to compare the experimental results to is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and Madgraph5 at LO in QCD for photons from the decay part of the process. The alternative prediction is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and a POWHEG+Pythia $\mathrm{tt}$ simulation at NLO in QCD for photons from the decay part of the process. The theory predictions are computed at fixed order, at NLO in QCD, as described in Section 9.2 of the paper.

Normalized differential distributions of the photon $p_{\mathrm{T}}$. The nominal MC prediction used to compare the experimental results to is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and Madgraph5 at LO in QCD for photons from the decay part of the process. The alternative prediction is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and a POWHEG+Pythia $\mathrm{tt}$ simulation at NLO in QCD for photons from the decay part of the process. The theory predictions are computed at fixed order, at NLO in QCD, as described in Section 9.2 of the paper.

Absolute differential distributions of the $\Delta \phi (\ell,\ell)$. The nominal MC prediction used to compare the experimental results to is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and Madgraph5 at LO in QCD for photons from the decay part of the process. The alternative prediction is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and a POWHEG+Pythia $\mathrm{tt}$ simulation at NLO in QCD for photons from the decay part of the process. The theory predictions are computed at fixed order, at NLO in QCD, as described in Section 9.2 of the paper.

Normalized differential distributions of the $\Delta \phi (\ell,\ell)$. The nominal MC prediction used to compare the experimental results to is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and Madgraph5 at LO in QCD for photons from the decay part of the process. The alternative prediction is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and a POWHEG+Pythia $\mathrm{tt}$ simulation at NLO in QCD for photons from the decay part of the process. The theory predictions are computed at fixed order, at NLO in QCD, as described in Section 9.2 of the paper.

Absolute differential distributions of the ratio between the cross sections of $\mathrm{tt\gamma}$ and $\mathrm{tt}$, as a function of the leading top quark $p_{\mathrm{T}}$. The nominal MC prediction used to compare the experimental results to is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and Madgraph5 at LO in QCD for photons from the decay part of the process. The alternative prediction is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and a POWHEG+Pythia $\mathrm{tt}$ simulation at NLO in QCD for photons from the decay part of the process.

Absolute differential distributions of the ratio between the cross sections of $\mathrm{tt\gamma}$ and $\mathrm{tt}$, as a function of the leading lepton $p_{\mathrm{T}}$. The nominal MC prediction used to compare the experimental results to is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and Madgraph5 at LO in QCD for photons from the decay part of the process. The alternative prediction is obtained with Madgraph5 at NLO in QCD for photons from the production part of the process and a POWHEG+Pythia $\mathrm{tt}$ simulation at NLO in QCD for photons from the decay part of the process. The theory predictions are computed at fixed order, at NLO in QCD, as described in Section 9.2 of the paper.

Correlation matrix of the total uncertainty in the absolute differential cross section as a function of the leading top quark $p_{\mathrm{T}}$.

Correlation matrix of the statistical uncertainty in the absolute differential cross section as a function of the leading top quark $p_{\mathrm{T}}$.

Correlation matrix of the total uncertainty in the absolute differential cross section as a function of the $\Delta R (\gamma,\mathrm{tt})$.

Correlation matrix of the statistical uncertainty in the absolute differential cross section as a function of the $\Delta R (\gamma,\mathrm{tt})$.

Correlation matrix of the total uncertainty in the absolute differential cross section as a function of the min. $\Delta R (\gamma,\mathrm{t})$.

Correlation matrix of the statistical uncertainty in the absolute differential cross section as a function of the min. $\Delta R (\gamma,\mathrm{t})$.

Correlation matrix of the total uncertainty in the absolute differential cross section as a function of the $m(\mathrm{tt})$.

Correlation matrix of the statistical uncertainty in the absolute differential cross section as a function of the $m(\mathrm{tt})$.

Correlation matrix of the total uncertainty in the absolute differential cross section as a function of the leading lepton $p_{\mathrm{T}}$.

Correlation matrix of the statistical uncertainty in the absolute differential cross section as a function of the leading lepton $p_{\mathrm{T}}$.

Correlation matrix of the total uncertainty in the absolute differential cross section as a function of the photon $p_{\mathrm{T}}$.

Correlation matrix of the statistical uncertainty in the absolute differential cross section as a function of the photon $p_{\mathrm{T}}$.

Correlation matrix of the total uncertainty in the absolute differential cross section as a function of the $\Delta \phi (\ell,\ell)$.

Correlation matrix of the statistical uncertainty in the absolute differential cross section as a function of the $\Delta \phi (\ell,\ell)$.

Correlation matrix of the total uncertainty in the absolute differential $\mathrm{tt\gamma}$ / $\mathrm{tt}$ cross section ratio as a function of the leading top $p_{\mathrm{T}}$.

Correlation matrix of the statistical uncertainty in the absolute differential $\mathrm{tt\gamma}$ / $\mathrm{tt}$ cross section ratio as a function of the leading top $p_{\mathrm{T}}$.

Correlation matrix of the total uncertainty in the absolute differential $\mathrm{tt\gamma}$ / $\mathrm{tt}$ cross section ratio as a function of the leading lepton $p_{\mathrm{T}}$.

Correlation matrix of the statistical uncertainty in the absolute differential $\mathrm{tt\gamma}$ / $\mathrm{tt}$ cross section ratio as a function of the leading lepton $p_{\mathrm{T}}$.

Observed differential dijet spectrum using full Run-2 data.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for quark-quark type dijet resonances.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for quark-gluon type dijet resonances.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for gluon-gluon type dijet resonances.

The observed and expected 95% CL upper limits on the universal quark coupling $g_{q}'$ as a function of resonance mass for a leptophobic Z' resonance that only couples to quarks.

Predictions of a leading order (LO) QCD simulation, normalized to an integrated luminosity of 138 fb$^{-1}$. The number of events are examined within bins of the four-jet mass and the ratio $\alpha$, which is the average dijet mass divided by the four-jet mass.

The 68% probability contour in the $m_{\mathrm{4j}}$ vs. $\overline{m}_{\mathrm{2j}}$ plane from a signal simulation of a diquark with a width of 1.5% and a mass of 8.4 TeV, decaying to a pair of vector-like quarks, each with a mass of 2.1 TeV.

The 68% probability contour in the $m_{\mathrm{4j}}$ vs. $\overline{m}_{\mathrm{2j}}$ plane from a signal simulation of a diquark with a width of 5% and a mass of 8.4 TeV, decaying to a pair of vector-like quarks, each with a mass of 2.1 TeV.

The 68% probability contour in the $m_{\mathrm{4j}}$ vs. $\overline{m}_{\mathrm{2j}}$ plane from a signal simulation of a diquark with a width of 10% and a mass of 8.4 TeV, decaying to a pair of vector-like quarks, each with a mass of 2.1 TeV.

The 68% probability contour in the $m_{\mathrm{4j}}$ vs. $\alpha$ plane from a signal simulation of a diquark with a width of 1.5% and a mass of 8.4 TeV, decaying to a pair of vector-like quarks, each with a mass of 2.1 TeV.

The 68% probability contour in the $m_{\mathrm{4j}}$ vs. $\alpha$ plane from a signal simulation of a diquark with a width of 5% and a mass of 8.4 TeV, decaying to a pair of vector-like quarks, each with a mass of 2.1 TeV.

The 68% probability contour in the $m_{\mathrm{4j}}$ vs. $\alpha$ plane from a signal simulation of a diquark with a width of 10% and a mass of 8.4 TeV, decaying to a pair of vector-like quarks, each with a mass of 2.1 TeV.

Signal differential distributions as a function of four-jet mass for $\alpha_{\mathrm{true}}$ = 0.25, diquark masses of 2, 5, 8.6 TeV and various widths, for all $\alpha$ bins inclusively. The integral of each distribution has been normalized to unity.

The product of acceptance, $A$, and efficiency, $\varepsilon$, of a resonant signal with $\alpha_{\mathrm{true}}$ = 0.25 vs. the diquark mass for various diquark widths, and for all $\alpha$ bins inclusively. The acceptance is defined as the fraction of generated events passing the kinematic selection criteria, while the efficiency is the fraction of signal events satisfying $m_{\mathrm{4j}} > 1.6$ TeV. We also show the signal acceptance alone in the curves where $\varepsilon = 1$.

The four-jet mass distribution in data for 0.22 < $\alpha$ < 0.24, fitted with three background-only functions (Dijet-3p, PowExp-3p and ModDijet-3p), each with three free parameters. Examples of predicted diquark resonances with $\alpha_{\mathrm{true}}$ = 0.25, $M_{\mathrm{S}}$ = 8.6 TeV, and $\Gamma/M_{\mathrm{S}}$ = 1.5%, 10% are also shown, with cross sections equal to the observed upper limits at 95% confidence level.

The four-jet mass distribution in data for 0.24 < $\alpha$ < 0.26, fitted with three background-only functions (Dijet-3p, PowExp-3p and ModDijet-3p), each with three free parameters. Examples of predicted diquark resonances with $\alpha_{\mathrm{true}}$ = 0.25, $M_{\mathrm{S}}$ = 8.6 TeV, and $\Gamma/M_{\mathrm{S}}$ = 1.5%, 10% are also shown, with cross sections equal to the observed upper limits at 95% confidence level.

The four-jet mass distribution in data for 0.26 < $\alpha$ < 0.28, fitted with three background-only functions (Dijet-3p, PowExp-3p and ModDijet-3p), each with three free parameters. Examples of predicted diquark resonances with $\alpha_{\mathrm{true}}$ = 0.25, $M_{\mathrm{S}}$ = 8.6 TeV and $\alpha_{\mathrm{true}}$ = 0.29, $M_{\mathrm{S}}$ = 3.6 TeV, each shown for widths of $\Gamma/M_{\mathrm{S}}$ = 1.5% and 10% are also included, with cross sections equal to the observed upper limits at 95% confidence level.

The four-jet mass distribution in data for 0.28 < $\alpha$ < 0.30, fitted with three background-only functions (Dijet-3p, PowExp-3p and ModDijet-3p), each with three free parameters. Examples of predicted diquark resonances with $\alpha_{\mathrm{true}}$ = 0.25, $M_{\mathrm{S}}$ = 8.6 TeV and $\alpha_{\mathrm{true}}$ = 0.29, $M_{\mathrm{S}}$ = 3.6 TeV, each shown for widths of $\Gamma/M_{\mathrm{S}}$ = 1.5% and 10% are also included, with cross sections equal to the observed upper limits at 95% confidence level.

The four-jet mass distribution in data for 0.30 < $\alpha$ < 0.32, fitted with three background-only functions (Dijet-3p, PowExp-3p and ModDijet-3p), each with three free parameters. Examples of predicted diquark resonances with $\alpha_{\mathrm{true}}$ = 0.25, $M_{\mathrm{S}}$ = 8.6 TeV and $\alpha_{\mathrm{true}}$ = 0.29, $M_{\mathrm{S}}$ = 3.6 TeV, each shown for widths of $\Gamma/M_{\mathrm{S}}$ = 1.5% and 10% are also included, with cross sections equal to the observed upper limits at 95% confidence level.

The four-jet mass distribution in data for 0.32 < $\alpha$ < 0.34, fitted with three background-only functions (Dijet-3p, PowExp-3p and ModDijet-3p), each with three free parameters. Examples of predicted diquark resonances with $\alpha_{\mathrm{true}}$ = 0.25, $M_{\mathrm{S}}$ = 8.6 TeV, and $\Gamma/M_{\mathrm{S}}$ = 1.5%, 10% are also shown, with cross sections equal to the observed upper limits at 95% confidence level.

The inclusive four-jet mass distribution in data for $\alpha$ > 0.10, fitted with three background-only functions (Dijet-5p, PowExp-5p and ModDijet-5p), each with five free parameters. Examples of predicted diquark resonances with $\alpha_{\mathrm{true}}$ = 0.25, $M_{\mathrm{S}}$ = 8.6 TeV and $\alpha_{\mathrm{true}}$ = 0.29, $M_{\mathrm{S}}$ = 3.6 TeV, each shown for widths of $\Gamma/M_{\mathrm{S}}$ = 1.5% and 10% are also included, with cross sections equal to the observed upper limits at 95% confidence level.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.25$ and width of the initial resonance Y equal to 1.5%. The corresponding expected limits and their variations at the 1 and 2 standard deviation (s.d.) levels are also included. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate a mediator width equal to 1.5%.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.25$ and width of the initial resonance Y equal to 5%. The corresponding expected limits and their variations at the 1 and 2 standard deviation (s.d.) levels are also included. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate a mediator width equal to 5%.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.25$ and width of the initial resonance Y equal to 10%. The corresponding expected limits and their variations at the 1 and 2 standard deviation (s.d.) levels are also included. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate a mediator width equal to 10%.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.11$ and width of the initial resonance Y equal to 10%. The corresponding expected limits and their variations at the 1 and 2 standard deviation (s.d.) levels are also included. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate a mediator width equal to 10%.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.13$ and width of the initial resonance Y equal to 10%. The corresponding expected limits and their variations at the 1 and 2 standard deviation (s.d.) levels are also included. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate a mediator width equal to 10%.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.15$ and width of the initial resonance Y equal to 10%. The corresponding expected limits and their variations at the 1 and 2 standard deviation (s.d.) levels are also included. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate a mediator width equal to 10%.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.17$ and width of the initial resonance Y equal to 10%. The corresponding expected limits and their variations at the 1 and 2 standard deviation (s.d.) levels are also included. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate a mediator width equal to 10%.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.19$ and width of the initial resonance Y equal to 10%. The corresponding expected limits and their variations at the 1 and 2 standard deviation (s.d.) levels are also included. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate a mediator width equal to 10%.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.21$ and width of the initial resonance Y equal to 10%. The corresponding expected limits and their variations at the 1 and 2 standard deviation (s.d.) levels are also included. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate a mediator width equal to 10%.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.23$ and width of the initial resonance Y equal to 10%. The corresponding expected limits and their variations at the 1 and 2 standard deviation (s.d.) levels are also included. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate a mediator width equal to 10%.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.27$ and width of the initial resonance Y equal to 10%. The corresponding expected limits and their variations at the 1 and 2 standard deviation (s.d.) levels are also included. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate a mediator width equal to 10%.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.29$ and width of the initial resonance Y equal to 10%. The corresponding expected limits and their variations at the 1 and 2 standard deviation (s.d.) levels are also included. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate a mediator width equal to 10%.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.31$ and width of the initial resonance Y equal to 10%. The corresponding expected limits and their variations at the 1 and 2 standard deviation (s.d.) levels are also included. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate a mediator width equal to 10%.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.33$ and width of the initial resonance Y equal to 10%. The corresponding expected limits and their variations at the 1 and 2 standard deviation (s.d.) levels are also included. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate a mediator width equal to 10%.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.42$ and width of the initial resonance Y equal to 10%. The corresponding expected limits and their variations at the 1 and 2 standard deviation (s.d.) levels are also included. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate a mediator width equal to 10%.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.11$ and widths of the initial resonance Y equal to 1.5, 5, and 10%. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate the corresponding widths.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.13$ and widths of the initial resonance Y equal to 1.5, 5, and 10%. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate the corresponding widths.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.15$ and widths of the initial resonance Y equal to 1.5, 5, and 10%. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate the corresponding widths.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.17$ and widths of the initial resonance Y equal to 1.5, 5, and 10%. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate the corresponding widths.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.19$ and widths of the initial resonance Y equal to 1.5, 5, and 10%. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate the corresponding widths.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.21$ and widths of the initial resonance Y equal to 1.5, 5, and 10%. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate the corresponding widths.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.23$ and widths of the initial resonance Y equal to 1.5, 5, and 10%. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate the corresponding widths.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.27$ and widths of the initial resonance Y equal to 1.5, 5, and 10%. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate the corresponding widths.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.29$ and widths of the initial resonance Y equal to 1.5, 5, and 10%. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate the corresponding widths.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.31$ and widths of the initial resonance Y equal to 1.5, 5, and 10%. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate the corresponding widths.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.33$ and widths of the initial resonance Y equal to 1.5, 5, and 10%. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate the corresponding widths.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}} / M_{\mathrm{Y}} = 0.42$ and widths of the initial resonance Y equal to 1.5, 5, and 10%. Limits are compared to predictions for scalar $\mathrm{S}_{\mathrm{uu}}$ and $\mathrm{S}_{\mathrm{dd}}$ diquarks with couplings to pairs of up and down quarks, $y_{\mathrm{uu}}$ and $y_{\mathrm{dd}}$, and to pairs of vector-like quarks, $y_{\chi}$ and $y_{\omega}$, set appropriately in order to generate the corresponding widths.

Observed local $p$-value for a four-jet resonance, Y, decaying to a pair of dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}}/M_{\mathrm{Y}}$ = 0.25, and various widths of Y superimposed.

Observed local $p$-value for a four-jet resonance, Y, decaying to a pair of dijet resonances, X, with $\alpha_{\mathrm{true}} = M_{\mathrm{X}}/M_{\mathrm{Y}}$ = 0.29, and various widths of Y superimposed.

The table presents the cumulative cutflow for a signal with $M_{\mathrm{S}} = 2.0$ TeV, $M_{\chi} = 0.5$ TeV and different width hypotheses ($\Gamma/M_{\mathrm{S}} =$ 1.5, 5, and 10%). Each row corresponds to the number of signal events that survive all cuts up to and including the one listed. The percentage in parentheses shows the efficiency of the current cut alone, defined as the ratio of the number of events that survive all cuts up to and including this one to the number of events that survived all previous cuts.

The table presents the cumulative cutflow for a signal with $M_{\mathrm{S}} = 5.0$ TeV, $M_{\chi} = 1.25$ TeV and different width hypotheses ($\Gamma/M_{\mathrm{S}} =$ 1.5, 5, and 10%). Each row corresponds to the number of signal events that survive all cuts up to and including the one listed. The percentage in parentheses shows the efficiency of the current cut alone, defined as the ratio of the number of events that survive all cuts up to and including this one to the number of events that survived all previous cuts.

The table presents the cumulative cutflow for a signal with $M_{\mathrm{S}} = 8.6$ TeV, $M_{\chi} = 2.15$ TeV and different width hypotheses ($\Gamma/M_{\mathrm{S}} =$ 1.5, 5, and 10%). Each row corresponds to the number of signal events that survive all cuts up to and including the one listed. The percentage in parentheses shows the efficiency of the current cut alone, defined as the ratio of the number of events that survive all cuts up to and including this one to the number of events that survived all previous cuts.

Differential cross-section in bins of subleading muon $p_\mathrm{T]$. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of leading muon $\eta$. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of subleading muon $\eta$. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of leading muon $\phi$. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of subleading muon $\phi$. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of leading charged particle jet $p_\mathrm{T]$. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of subleading charged particle jet $p_\mathrm{T]$. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of leading charged particle jet rapidity. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of subleading charged particle jet rapidity. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of leading charged particle jet azimuth. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of subleading charged particle jet azimuth. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of leading charged particle jet mass. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of subleading charged particle jet mass. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of leading charged particle jet constituent multiplicity. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of subleading charged particle jet constituent multiplicity. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of leading charged particle jet $\tau_1$. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of subleading charged particle jet $\tau_1$. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of leading charged particle jet $\tau_2$. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of subleading charged particle jet $\tau_2$. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of leading charged particle jet $\tau_3$. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of subleading charged particle jet $\tau_3$. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of leading charged particle jet $\tau_{21}$. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross-section in bins of $\Delta R$ between the leading charged particle jet and the dilepton system. The actual measurement is unbinned and available with examples at <a href="https://gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024">gitlab.cern.ch/atlas-physics/public/sm-z-jets-omnifold-2024</a>

Differential cross sections normalized to the fiducial cross section as a function of the $p_T$ of the second-highest-$p_T$ jet

Differential cross sections normalized to the fiducial cross section as a function of the $|\eta|$ of the highest-$p_T$ jet

Differential cross sections normalized to the fiducial cross section as a function of the $|\eta|$ of the second-highest-$p_T$ jet

Differential cross sections normalized to the fiducial cross section as a function of the pseudorapidity difference between the two highest-$p_T$ jets in the event

Differential cross sections normalized to the fiducial cross section as a function of the invariant mass of the two highest-$p_T$ jets in the event

Differential cross sections normalized to the fiducial cross section as a function of the invariant mass of the four-lepton system, in the full $m_{4l}$ range

Differential cross sections normalized to the fiducial cross section as a function of the invariant mass of the four-lepton system in events with 0 jet, in the on-shell ZZ region

Differential cross sections normalized to the fiducial cross section as a function of the invariant mass of the four-lepton system in events with 1 jet, in the on-shell ZZ region

Differential cross sections normalized to the fiducial cross section as a function of the invariant mass of the four-lepton system in events with 2 jets, in the on-shell ZZ region

Differential cross sections normalized to the fiducial cross section as a function of the invariant mass of the four-lepton system in events with at least 3 jets, in the on-shell ZZ region

Differential cross sections normalized to the fiducial cross section as a function of the invariant mass of the four-lepton system in events with 0 jet, in the full $m_{4l}$ range

Differential cross sections normalized to the fiducial cross section as a function of the invariant mass of the four-lepton system in events with 1 jet, in the full $m_{4l}$ range

Differential cross sections normalized to the fiducial cross section as a function of the invariant mass of the four-lepton system in events with 2 jets, in the full $m_{4l}$ range

Differential cross sections normalized to the fiducial cross section as a function of the invariant mass of the four-lepton system in events with at least 3 jets, in the full $m_{4l}$ range

Observed and expected distributions of the collinear mass in the $\tau_\mathrm{h}$+jet no-btag category with the BDT requirements selecting the most signal-like events. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Observed and expected distributions of the collinear mass in the e+jet no-btag category with the BDT requirements selecting the most signal-like events. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Observed and expected distributions of the collinear mass in the $\mu$+jet no-btag category with the BDT requirements selecting the most signal-like events. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Expected and observed upper limits at 95% CL on the scalar lepton-induced LQ production cross section times branching fraction for a LQ coupled to b quarks and $\tau$ leptons, using $\lambda = 1.5$.

Expected and observed upper limits at 95% CL on the scalar lepton-induced LQ production cross section times branching fraction for a LQ coupled to light-flavor quarks and $\tau$ leptons, using $\lambda = 1.5$.

Expected upper limit at 95% CL on the coupling strength $\lambda$ of a scalar LQ to b quarks and $\tau$ leptons.

Expected upper limit at 95% CL on the coupling strength $\lambda$ of a scalar LQ to light-flavor quarks and $\tau$ leptons.

Observed and expected distributions of the collinear mass in the $\tau_\mathrm{h}$+jet btag category with the lowest BDT requirement. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Observed and expected distributions of the collinear mass in the e+jet btag category with the lowest BDT requirement. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Observed and expected distributions of the collinear mass in the $\mu$+jet btag category with the lowest BDT requirement. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Observed and expected distributions of the collinear mass in the $\tau_\mathrm{h}$+jet btag category with the intermediate BDT requirement. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Observed and expected distributions of the collinear mass in the e+jet btag category with intermediate BDT requirement. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Observed and expected distributions of the collinear mass in the $\mu$+jet btag category with intermediate BDT requirement. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Observed and expected distributions of the collinear mass in the $\tau_\mathrm{h}$+jet no-btag category with the lowest BDT requirement. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Observed and expected distributions of the collinear mass in the e+jet no-btag category with the lowest BDT requirement. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Observed and expected distributions of the collinear mass in the $\tau_\mathrm{h}$+jet btag category with the lowest BDT requirement. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Observed and expected distributions of the collinear mass in the $\tau_\mathrm{h}$+jet no-btag category with low BDT requirement. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Observed and expected distributions of the collinear mass in the e+jet no-btag category with low BDT requirement. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Observed and expected distributions of the collinear mass in the $\mu$+jet no-btag category with low BDT requirement. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Observed and expected distributions of the collinear mass in the $\tau_\mathrm{h}$+jet no-btag category with intermediate BDT requirement. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Observed and expected distributions of the collinear mass in the e+jet btag category with intermediate BDT requirement. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Observed and expected distributions of the collinear mass in the $\mu$+jet no-btag category with intermediate BDT requirement. The signal hypothesis corresponds to a scalar leptoquark coupled to u quarks and $\tau$ leptons with a coupling strength $\lambda$ equal to 1.5.

Expected and observed upper limits at 95% CL on the scalar lepton-induced LQ production cross section times branching fraction for a LQ coupled to b quarks and $\tau$ leptons, using $\lambda = 1.0$.

Expected and observed upper limits at 95% CL on the scalar lepton-induced LQ production cross section times branching fraction for a LQ coupled to b quarks and $\tau$ leptons, using $\lambda = 2.0$.

Expected and observed upper limits at 95% CL on the scalar lepton-induced LQ production cross section times branching fraction for a LQ coupled to b quarks and $\tau$ leptons, using $\lambda = 3.0$.

Expected and observed upper limits at 95% CL on the scalar lepton-induced LQ production cross section times branching fraction for a LQ coupled to light-flavor quarks and $\tau$ leptons, using $\lambda = 0.5$.

Expected and observed upper limits at 95% CL on the scalar lepton-induced LQ production cross section times branching fraction for a LQ coupled to light-flavor quarks and $\tau$ leptons, using $\lambda = 1.0$.

Expected and observed upper limits at 95% CL on the scalar lepton-induced LQ production cross section times branching fraction for a LQ coupled to light-flavor quarks and $\tau$ leptons, using $\lambda = 2.0$.

Observed and expected distributions of the jet multiplicity in the e+jet btag control region.

Observed and expected distributions of the jet multiplicity in the $\mu$+jet btag control region.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances decaying to a quark-gluon pair, with $M(X)/M(Y) = 0.17$. The corresponding expected limits and their variations at the 1 and 2 standard deviation levels are also shown. Limits are compared to predictions for a scalar diquark with couplings to pairs of up quarks, $y_{uu}$ = 0.4, and to pairs of vector-like quarks, $y_{χ}$ = 0.6.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances decaying to a quark-gluon pair, with $M(X)/M(Y) = 0.19$. The corresponding expected limits and their variations at the 1 and 2 standard deviation levels are also shown. Limits are compared to predictions for a scalar diquark with couplings to pairs of up quarks, $y_{uu}$ = 0.4, and to pairs of vector-like quarks, $y_{χ}$ = 0.6.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances decaying to a quark-gluon pair, with $M(X)/M(Y) = 0.21$. The corresponding expected limits and their variations at the 1 and 2 standard deviation levels are also shown. Limits are compared to predictions for a scalar diquark with couplings to pairs of up quarks, $y_{uu}$ = 0.4, and to pairs of vector-like quarks, $y_{χ}$ = 0.6.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances decaying to a quark-gluon pair, with $M(X)/M(Y) = 0.23$. The corresponding expected limits and their variations at the 1 and 2 standard deviation levels are also shown. Limits are compared to predictions for a scalar diquark with couplings to pairs of up quarks, $y_{uu}$ = 0.4, and to pairs of vector-like quarks, $y_{χ}$ = 0.6.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances decaying to a quark-gluon pair, with $M(X)/M(Y) = 0.25$. The corresponding expected limits and their variations at the 1 and 2 standard deviation levels are also shown. Limits are compared to predictions for a scalar diquark with couplings to pairs of up quarks, $y_{uu}$ = 0.4, and to pairs of vector-like quarks, $y_{χ}$ = 0.6.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances decaying to a quark-gluon pair, with $M(X)/M(Y) = 0.27$. The corresponding expected limits and their variations at the 1 and 2 standard deviation levels are also shown. Limits are compared to predictions for a scalar diquark with couplings to pairs of up quarks, $y_{uu}$ = 0.4, and to pairs of vector-like quarks, $y_{χ}$ = 0.6.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances decaying to a quark-gluon pair, with $M(X)/M(Y) = 0.29$. The corresponding expected limits and their variations at the 1 and 2 standard deviation levels are also shown. Limits are compared to predictions for a scalar diquark with couplings to pairs of up quarks, $y_{uu}$ = 0.4, and to pairs of vector-like quarks, $y_{χ}$ = 0.6.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances decaying to a quark-gluon pair, with $M(X)/M(Y) = 0.31$. The corresponding expected limits and their variations at the 1 and 2 standard deviation levels are also shown. Limits are compared to predictions for a scalar diquark with couplings to pairs of up quarks, $y_{uu}$ = 0.4, and to pairs of vector-like quarks, $y_{χ}$ = 0.6.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances decaying to a quark-gluon pair, with $M(X)/M(Y) = 0.33$. The corresponding expected limits and their variations at the 1 and 2 standard deviation levels are also shown. Limits are compared to predictions for a scalar diquark with couplings to pairs of up quarks, $y_{uu}$ = 0.4, and to pairs of vector-like quarks, $y_{χ}$ = 0.6.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances decaying to a quark-gluon pair, with $M(X)/M(Y) = 0.42$. The corresponding expected limits and their variations at the 1 and 2 standard deviation levels are also shown. Limits are compared to predictions for a scalar diquark with couplings to pairs of up quarks, $y_{uu}$ = 0.4, and to pairs of vector-like quarks, $y_{χ}$ = 0.6.

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for the non-resonant production of top squark pairs in the RPV SUSY decay scenario. The corresponding expected limits and their variations at the 1 and 2 standard deviation levels are also shown. Limits are compared to the top squark model cross section.

Observed differential four-jet mass spectrum for 0.22 < $\\a$ < 0.24. The cross-section is calculated by dividing the event yield by the bin width and luminosity.

Observed differential four-jet mass spectrum for 0.24 < $\\a$ < 0.26. The cross-section is calculated by dividing the event yield by the bin width and luminosity.

Observed differential four-jet mass spectrum for 0.26 < $\\a$ < 0.28. The cross-section is calculated by dividing the event yield by the bin width and luminosity.

Observed differential four-jet mass spectrum for all $\\a$ bins together. The cross-section is calculated by dividing the event yield by the bin width and luminosity.

Observed differential average dijet mass spectrum within three $\\a$ bins of the non-resonant search. The cross-section is calculated by dividing the event yield by the bin width and luminosity.

Normalized differential cross section distribution as a function of the leading b jet transverse momentum for the Z + >= 1 b jet events

Differential cross section distribution as a function of the leading b jet absolute pseudorapidity for the Z + >= 1 b jet events

Normalized differential cross section distribution as a function of the leading b jet absolute pseudorapidity for the Z + >= 1 b jet events

Differential cross section distribution as a function of the leading b jet transverse momentum for Z +>= 1 b jet events

Normalized differential cross section distribution as a function of azimuthal difference between Z boson and the leading b jet for the Z + >= 1 b jet events

Differential cross section distribution as a function of the rapidity difference between Z boson and the leading b jet for the Z + >= 1 b jet events

Normalized differential cross section distribution as a function of the rapidity difference between Z boson and the leading b jet for the Z + >= 1 b jet events

Differential cross section distribution as a function of the angular separation between the Z boson and the leading b jet for the Z + >= 1 b jet events

Normalized differential cross section distribution as a function of the angular separation between the Z boson and the leading b jet for the Z + >= 1 b jet events

Differential cross section distribution as a function of the leading b jet transverse momentum for the Z + >= 2 b jet events

Normalized differential cross section distribution as a function of the leading b jet transverse momentum for the Z + >= 2 b jet events

Differential cross section distribution as a function of the leading b jet absolute pseudorapidity

Normalized differential cross section distribution as a function of the leading b jet absolute pseudorapidity

Differential cross section distribution as a function of the subleading b jet transverse momentum for the Z + >= 2 b jet events

Normalized differential cross section distribution as a function of the subleading b jet transverse momentum for the Z + >= 2 b jet events

Differential cross section distribution as a function of the Z boson transverse momentum for the Z + >= 2 b jet events

Normalized differential cross section distribution as a function of the Z boson transverse momentum for the Z + >= 2 b jet events

Differential cross section as a function of the angular separation between two b jets for the Z + >= 2 b jet events

Normalized differential cross section as a function of the angular separtion between two b jets for the Z + >= 2 b jet events

Differential cross section as a function of the minimum angular separation between the Z boson and two b jets for the Z + >= 2 b jet events

Normalized differential cross section as a function of the minimum angular separation between the Z boson and two b jets for the Z + >= 2 b jet events

Differential cross section as a function of the asymmetry of the Z + >= 2 b jets system

Normalized differential cross section as a function of the asymmetry of the Z + >= 2 b jets system

Differential cross section as a function of the invariant mass of two b jets for the Z + >= 2 b jet events

Normalized differential cross section as a function of the invariant mass of two b jets for the Z + >= 2 b jet events

Differential cross section as a function of the invariant mass of the Z boson and two b jets for the Z + >= 2 b jet events

Normalized differential cross section as a function of invariant mass of the Z boson and two b jets for the Z + >= 2 b jet events

Distributions of the cross section ratios as a function of the leading b jet transverse momentum

Distributions of the cross section ratios as a function of the leading b jet absolute pseudorapidity

Differential fiducial cross section of the Z boson $|y|$ in events with $Z(\rightarrow ll)\ge+1$ b-jets. The statistical uncertainties and the individual components of systematic uncertainty are given in each bin. Statistical uncertainties are bin-to-bin uncorrelated.

Differential fiducial cross section of the leading b-jet $|y|$ in events with $Z(\rightarrow ll)\ge+1$ b-jets. The statistical uncertainties and the individual components of systematic uncertainty are given in each bin. Statistical uncertainties are bin-to-bin uncorrelated.

Differential fiducial cross section of the $\Delta \phi$ between Z boson and leading $b$-jet in events with $Z(\rightarrow ll)\ge+1$ b-jets. The statistical uncertainties and the individual components of systematic uncertainty are given in each bin. Statistical uncertainties are bin-to-bin uncorrelated.

Differential fiducial cross section of the $\Delta y$ between Z boson and leading $b$-jet in events with $Z(\rightarrow ll)\ge+1$ b-jets. The statistical uncertainties and the individual components of systematic uncertainty are given in each bin. Statistical uncertainties are bin-to-bin uncorrelated.

Differential fiducial cross section of the $\Delta R$ between Z boson and leading $b$-jet in events with $Z(\rightarrow ll)\ge+1$ b-jets. The statistical uncertainties and the individual components of systematic uncertainty are given in each bin. Statistical uncertainties are bin-to-bin uncorrelated.

Differential fiducial cross section of the $\Delta \phi$ between the first two leading $b$-jets in events with $Z(\rightarrow ll)\ge+2$ b-jets. The statistical uncertainties and the individual components of systematic uncertainty are given in each bin. Statistical uncertainties are bin-to-bin uncorrelated.

Differential fiducial cross section of the $\Delta y$ between the first two leading $b$-jets in events with $Z(\rightarrow ll)\ge+2$ b-jets. The statistical uncertainties and the individual components of systematic uncertainty are given in each bin. Statistical uncertainties are bin-to-bin uncorrelated.

Differential fiducial cross section of the $\Delta R$ between the first two leading $b$-jets in events with $Z(\rightarrow ll)\ge+2$ b-jets. The statistical uncertainties and the individual components of systematic uncertainty are given in each bin. Statistical uncertainties are bin-to-bin uncorrelated.

Differential fiducial cross section of the invariant mass of the first two leading $b$-jets in events with $Z(\rightarrow ll)\ge+2$ b-jets. The statistical uncertainties and the individual components of systematic uncertainty are given in each bin. Statistical uncertainties are bin-to-bin uncorrelated.

Differential fiducial cross section of the Z boson $p_{\text{T}}$ in events with $Z(\rightarrow ll)\ge+2$ b-jets. The statistical uncertainties and the individual components of systematic uncertainty are given in each bin. Statistical uncertainties are bin-to-bin uncorrelated.

Differential fiducial cross section of the $p_{\text{T}}$ of the first two leading $b$-jets in events with $Z(\rightarrow ll)\ge+2$ b-jets. The statistical uncertainties and the individual components of systematic uncertainty are given in each bin. Statistical uncertainties are bin-to-bin uncorrelated.

Differential fiducial cross section of the ratio between the $p_{\text{T}}$ and the invariant mass of the first two leading $b$-jets in events with $Z(\rightarrow ll)\ge+2$ b-jets. The statistical uncertainties and the individual components of systematic uncertainty are given in each bin. Statistical uncertainties are bin-to-bin uncorrelated.

The measured fiducial cross section vs $m(\ell\ell\gamma)$. The central values are provided along with the statistical and systematic uncertainties together with the sign information. The statistical and "Uncor" uncertainty should be treated as uncorrelated bin-to-bin, while the rest are correlated between bins, and they are written as signed NP variations. The parton-to-particle correction factor $C_{theory}$ is the ratio of the cross-section predicted by Sherpa LO samples at particle level within the fiducial phase-space region defined in Table 4 to the predicted cross-section at parton level within the same fiducial region but with the smooth-cone isolation prescription defined above replacing the particle-level photon isolation criterion, and with Born-level leptons in place of dressed leptons. This correction should be applied on fixed order parton-level calculations. The systematic uncertainty is evaluated from a comparison with the correction factor obtained using events generated with Sherpa 2.2.2 at NLO. The uncertainty is defined as Max(stat error, systematic difference between Sherpa LO and Sherpa 2.2.2 NLO), and cannot be considered correlated bin-to-bin. In the case that the calculations are valid for dressed leptons, a modified correction factor excluding the Born-to-dressed lepton correction should be applied instead. This correction only takes into account the particle-level isolation criteria, and is provided separately here. The Sherpa 2.2.8 NLO cross-sections given below include a small contribution from EW $Z\gamma jj$ production.

The measured fiducial cross section vs $p_{\mathrm{T}}^{\ell\ell\gamma}$. The central values are provided along with the statistical and systematic uncertainties together with the sign information. The statistical and "Uncor" uncertainty should be treated as uncorrelated bin-to-bin, while the rest are correlated between bins, and they are written as signed NP variations. The parton-to-particle correction factor $C_{theory}$ is the ratio of the cross-section predicted by Sherpa LO samples at particle level within the fiducial phase-space region defined in Table 4 to the predicted cross-section at parton level within the same fiducial region but with the smooth-cone isolation prescription defined above replacing the particle-level photon isolation criterion, and with Born-level leptons in place of dressed leptons. This correction should be applied on fixed order parton-level calculations. The systematic uncertainty is evaluated from a comparison with the correction factor obtained using events generated with Sherpa 2.2.2 at NLO. The uncertainty is defined as Max(stat error, systematic difference between Sherpa LO and Sherpa 2.2.2 NLO), and cannot be considered correlated bin-to-bin. In the case that the calculations are valid for dressed leptons, a modified correction factor excluding the Born-to-dressed lepton correction should be applied instead. This correction only takes into account the particle-level isolation criteria, and is provided separately here. The Sherpa 2.2.8 NLO cross-sections given below include a small contribution from EW $Z\gamma jj$ production.

The measured fiducial cross section vs $\Delta\phi(ll,\gamma)$. The central values are provided along with the statistical and systematic uncertainties together with the sign information. The statistical and "Uncor" uncertainty should be treated as uncorrelated bin-to-bin, while the rest are correlated between bins, and they are written as signed NP variations. The parton-to-particle correction factor $C_{theory}$ is the ratio of the cross-section predicted by Sherpa LO samples at particle level within the fiducial phase-space region defined in Table 4 to the predicted cross-section at parton level within the same fiducial region but with the smooth-cone isolation prescription defined above replacing the particle-level photon isolation criterion, and with Born-level leptons in place of dressed leptons. This correction should be applied on fixed order parton-level calculations. The systematic uncertainty is evaluated from a comparison with the correction factor obtained using events generated with Sherpa 2.2.2 at NLO. The uncertainty is defined as Max(stat error, systematic difference between Sherpa LO and Sherpa 2.2.2 NLO), and cannot be considered correlated bin-to-bin. In the case that the calculations are valid for dressed leptons, a modified correction factor excluding the Born-to-dressed lepton correction should be applied instead. This correction only takes into account the particle-level isolation criteria, and is provided separately here. The Sherpa 2.2.8 NLO cross-sections given below include a small contribution from EW $Z\gamma jj$ production.

The measured fiducial cross section vs $p_{\mathrm{T}}^{\ell\ell\gamma}/m(\ell\ell\gamma)$. The central values are provided along with the statistical and systematic uncertainties together with the sign information. The statistical and "Uncor" uncertainty should be treated as uncorrelated bin-to-bin, while the rest are correlated between bins, and they are written as signed NP variations. The parton-to-particle correction factor $C_{theory}$ is the ratio of the cross-section predicted by Sherpa LO samples at particle level within the fiducial phase-space region defined in Table 4 to the predicted cross-section at parton level within the same fiducial region but with the smooth-cone isolation prescription defined above replacing the particle-level photon isolation criterion, and with Born-level leptons in place of dressed leptons. This correction should be applied on fixed order parton-level calculations. The systematic uncertainty is evaluated from a comparison with the correction factor obtained using events generated with Sherpa 2.2.2 at NLO. The uncertainty is defined as Max(stat error, systematic difference between Sherpa LO and Sherpa 2.2.2 NLO), and cannot be considered correlated bin-to-bin. In the case that the calculations are valid for dressed leptons, a modified correction factor excluding the Born-to-dressed lepton correction should be applied instead. This correction only takes into account the particle-level isolation criteria, and is provided separately here. The Sherpa 2.2.8 NLO cross-sections given below include a small contribution from EW $Z\gamma jj$ production.