Summary of the impact of the systematic uncertainties on the $t\bar{t}\gamma$ fiducial inclusive cross-section in the single-lepton and dilepton channels and their combination grouped into different categories. The quoted relative uncertainties are obtained by repeating the fit, fixing a set of nuisance parameters of the sources corresponding to each category to their post-fit values, and subtracting in quadrature the resulting uncertainty from the total uncertainty of the nominal fit. The total uncertainty is different from the sum in quadrature of the components due to correlations among nuisance parameters.

Absolute $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the single-lepton channel as a function of the $\Delta R(\gamma,b)_{min}$. The last bin of the distribution includes the overflow events.

Normalised $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the single-lepton channel as a function of the $\Delta R(\gamma,b)_{min}$. The last bin of the distribution includes the overflow events.

Absolute $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the single-lepton channel as a function of the $\Delta R(\gamma,l)$. The last bin of the distribution includes the overflow events.

Normalised $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the single-lepton channel as a function of the $\Delta R(\gamma,l)$. The last bin of the distribution includes the overflow events.

Absolute $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the single-lepton channel as a function of the $\Delta R(l,j)_{min}$. The last bin of the distribution includes the overflow events.

Normalised $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the single-lepton channel as a function of the $\Delta R(l,j)_{min}$. The last bin of the distribution includes the overflow events.

Absolute $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the dilepton channel as a function of the $\Delta R(\gamma,b)_{min}$. The last bin of the distribution includes the overflow events.

Normalised $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the dilepton channel as a function of the $\Delta R(\gamma,b)_{min}$. The last bin of the distribution includes the overflow events.

Absolute $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the dilepton channel as a function of the $\Delta R(\gamma,l)_{min}$. The last bin of the distribution includes the overflow events.

Normalised $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the dilepton channel as a function of the $\Delta R(\gamma,l)_{min}$. The last bin of the distribution includes the overflow events.

Absolute $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the dilepton channel as a function of the $\Delta R(l,j)_{min}$. The last bin of the distribution includes the overflow events.

Normalised $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the dilepton channel as a function of the $\Delta R(l,j)_{min}$. The last bin of the distribution includes the overflow events.

Absolute $t\bar{t}\gamma$ production differential cross-sections measured in the combined fiducial phase space of the single-lepton and dilepton channels as a function of the photon $p_T$. The last bin of the distributions includes the overflow events.

Normalised $t\bar{t}\gamma$ production differential cross-sections measured in the combined fiducial phase space of the single-lepton and dilepton channels as a function of the photon $p_T$. The last bin of the distributions includes the overflow events.

Absolute $t\bar{t}\gamma$ production differential cross-sections measured in the combined fiducial phase space of the single-lepton and dilepton channels as a function of the photon $|\eta|$.

Normalised $t\bar{t}\gamma$ production differential cross-sections measured in the combined fiducial phase space of the single-lepton and dilepton channels as a function of the photon $|\eta|$.

Absolute differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the single-lepton channel as a function of the $p_T(\gamma)$. The last bin of the distribution includes the overflow events.

Normalised differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the single-lepton channel as a function of the $p_T(\gamma)$. The last bin of the distribution includes the overflow events.

Absolute differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the single-lepton channel as a function of the $|\eta(\gamma)|$.

Normalised differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the single-lepton channel as a function of the $|\eta(\gamma)|$.

Absolute differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the single-lepton channel as a function of the $p_T(j_1)$. The last bin of the distribution includes the overflow events.

Normalised differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the single-lepton channel as a function of the $p_T(j_1)$. The last bin of the distribution includes the overflow events.

Absolute differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the single-lepton channel as a function of the $\Delta R(\gamma,b)_{min}$. The last bin of the distribution includes the overflow events.

Normalised differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the single-lepton channel as a function of the $\Delta R(\gamma,b)_{min}$. The last bin of the distribution includes the overflow events.

Absolute differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the single-lepton channel as a function of the $\Delta R(\gamma,l)$. The last bin of the distribution includes the overflow events.

Normalised differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the single-lepton channel as a function of the $\Delta R(\gamma,l)$. The last bin of the distribution includes the overflow events.

Absolute differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the single-lepton channel as a function of the $\Delta R(l,j)_{min}$. The last bin of the distribution includes the overflow events.

Normalised differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the single-lepton channel as a function of the $\Delta R(l,j)_{min}$. The last bin of the distribution includes the overflow events.

Absolute differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $|\Delta \eta(l,l)|$ . The last bin of the distribution includes the overflow events.

Normalised differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $|\Delta \eta(l,l)|$ . The last bin of the distribution includes the overflow events.

Absolute differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $\Delta \phi(l,l)$ . The last bin of the distribution includes the overflow events.

Normalised differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $\Delta \phi(l,l)$ . The last bin of the distribution includes the overflow events.

Absolute differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $p_T(l,l)$. The last bin of the distribution includes the overflow events.

Normalised differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $p_T(l,l)$. The last bin of the distribution includes the overflow events.

Absolute differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $\Delta R(\gamma,l_1)$. The last bin of the distribution includes the overflow events.

Normalised differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $\Delta R(\gamma,l_1)$. The last bin of the distribution includes the overflow events.

Absolute differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $\Delta R(\gamma,l_2)$. The last bin of the distribution includes the overflow events.

Normalised differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $\Delta R(\gamma,l_2)$. The last bin of the distribution includes the overflow events.

Absolute $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the single-lepton channel as a function of the $p_T(\gamma)$. The last bin of the distribution includes the overflow events.

Normalised $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the single-lepton channel as a function of the $p_T(\gamma)$. The last bin of the distribution includes the overflow events.

Absolute $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the single-lepton channel as a function of the $|\eta(\gamma)|$.

Normalised $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the single-lepton channel as a function of the $|\eta(\gamma)|$.

Absolute $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the single-lepton channel as a function of the $p_T(j_1)$. The last bin of the distribution includes the overflow events.

Normalised $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the single-lepton channel as a function of the $p_T(j_1)$. The last bin of the distribution includes the overflow events.

Absolute $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the dilepton channel as a function of the $p_T(\gamma)$. The last bin of the distribution includes the overflow events.

Normalised $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the dilepton channel as a function of the $p_T(\gamma)$. The last bin of the distribution includes the overflow events.

Absolute $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the dilepton channel as a function of the $|\eta(\gamma)|$.

Normalised $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the dilepton channel as a function of the $|\eta(\gamma)|$.

Absolute $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the dilepton channel as a function of the $p_T(j_1)$. The last bin of the distribution includes the overflow events.

Normalised $t\bar{t}\gamma$ production differential cross-sections measured in fiducial phase space in the dilepton channel as a function of the $p_T(j_1)$. The last bin of the distribution includes the overflow events.

Absolute differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $p_T(\gamma)$. The last bin of the distribution includes the overflow events.

Normalised differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $p_T(\gamma)$. The last bin of the distribution includes the overflow events.

Absolute differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $|\eta(\gamma)|$.

Normalised differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $|\eta(\gamma)|$.

Absolute differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $p_T(j_1)$. The last bin of the distribution includes the overflow events.

Normalised differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the single-lepton channel as a function of the $p_T(j_1)$. The last bin of the distribution includes the overflow events.

Absolute differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $\Delta R(\gamma,b)_{min}$. The last bin of the distribution includes the overflow events.

Normalised differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $\Delta R(\gamma,b)_{min}$. The last bin of the distribution includes the overflow events.

Absolute differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $\Delta R(\gamma,l)_{min}$. The last bin of the distribution includes the overflow events.

Normalised differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $\Delta R(\gamma,l)_{min}$. The last bin of the distribution includes the overflow events.

Absolute differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $\Delta R(l,j)_{min}$. The last bin of the distribution includes the overflow events.

Normalised differential cross-section of the total $t\bar{t}\gamma$ production and decay measured in fiducial phase space in the dilepton channel as a function of the $\Delta R(l,j)_{min}$. The last bin of the distribution includes the overflow events.

Observed and expected 68% and 95% credible intervals on $C/\Lambda^2\ [\text{TeV}^{-2} ]$ for the $C_{tW}$ operators and $C_{tB}$ obtained from the $t\bar{t}\gamma$ measurement, comparing the results obtained from the marginalised quadratic fit (‘marg.’) and the independent quadratic fits (‘indep.’). Also shown are the best-fit values (global mode) for each operator.

Observed and expected 68% and 95% credible intervals on $C/\Lambda^2\ [\text{TeV}^{-2} ]$ for the $C_{tW}$ operators and $C_{tB}$ obtained from a combined $t\bar{t}Z$ and $t\bar{t}\gamma$ measurements comparing the results obtained from the marginalised global quadratic fit (‘marg.’) and the independent quadratic fits (‘indep.’). Also shown are the best-fit values (global mode) for each operator.

Contributions of the systematic uncertainties grouped in categories in each bin of the measurement of the absolute $t\bar{t}\gamma$ production differential cross-sections measured in the combined fiducial phase space of the single-lepton and dilepton channels as a function of the photon $p_T$. The relative uncertainties quoted are obtained by repeating the fit, fixing the set of nuisance parameters of the sources corresponding to each category to their post-fit values, and subtracting in quadrature the resulting uncertainty from the total uncertainty of the nominal fit.

Contributions of the systematic uncertainties grouped in categories in each bin of the measurement of the absolute $t\bar{t}\gamma$ production differential cross-sections measured in the combined fiducial phase space of the single-lepton and dilepton channels as a function of the photon $\eta$. The relative uncertainties quoted are obtained by repeating the fit, fixing the set of nuisance parameters of the sources corresponding to each category to their post-fit values, and subtracting in quadrature the resulting uncertainty from the total uncertainty of the nominal fit.

The observed upper limits on the cross-sections at 95% CL for the simplified SUSY model featuring the production of mass-degenerate pairs of wino-like $\widetilde{\chi}_{2}^{0}$ and $\widetilde{\chi}_{1}^{\pm}$ particles in association with at least two jets. The production modes considered are $\widetilde{\chi}_{2}^{0}\widetilde{\chi}_{1}^{\pm}$, $\widetilde{\chi}_{1}^{\pm}\widetilde{\chi}_{1}^{\mp}$, $\widetilde{\chi}_{2}^{0}\widetilde{\chi}_{2}^{0}$, and $\widetilde{\chi}_{1}^{\pm}\widetilde{\chi}_{1}^{\pm}$.

Truth-level signal acceptances in $\text{SR}_\text{2j}$ with BDT score $\in [0.88, 1.0]$. All of the considered production modes ($\widetilde{\chi}_{2}^{0}\widetilde{\chi}_{1}^{\pm}$, $\widetilde{\chi}_{1}^{\pm}\widetilde{\chi}_{1}^{\mp}$, $\widetilde{\chi}_{2}^{0}\widetilde{\chi}_{2}^{0}$, and $\widetilde{\chi}_{1}^{\pm}\widetilde{\chi}_{1}^{\pm}$) are included. The acceptance is defined as the fraction of accepted events divided by the total number of events in the generator-level signal Monte Carlo simulation. The generator-level selections are the same as the ones at reconstruction level.

Truth-level signal acceptances in $\text{SR}_{\geq\text{3j}}$ with BDT score $\in [0.88, 1.0]$. All of the considered production modes ($\widetilde{\chi}_{2}^{0}\widetilde{\chi}_{1}^{\pm}$, $\widetilde{\chi}_{1}^{\pm}\widetilde{\chi}_{1}^{\mp}$, $\widetilde{\chi}_{2}^{0}\widetilde{\chi}_{2}^{0}$, and $\widetilde{\chi}_{1}^{\pm}\widetilde{\chi}_{1}^{\pm}$) are included. The acceptance is defined as the fraction of accepted events divided by the total number of events in the generator-level signal Monte Carlo simulation. The generator-level selections are the same as the ones at reconstruction level.

Signal efficiencies in $\text{SR}_\text{2j}$ with BDT score $\in [0.88, 1.0]$. All of the considered production modes ($\widetilde{\chi}_{2}^{0}\widetilde{\chi}_{1}^{\pm}$, $\widetilde{\chi}_{1}^{\pm}\widetilde{\chi}_{1}^{\mp}$, $\widetilde{\chi}_{2}^{0}\widetilde{\chi}_{2}^{0}$, and $\widetilde{\chi}_{1}^{\pm}\widetilde{\chi}_{1}^{\pm}$) are included. The efficiency is defined by the number of events of reconstructed-level signal simulation divided by the number of events obtained at generator level. The generator-level selections are the same as the ones at reconstruction level.

Signal efficiencies in $\text{SR}_{\geq\text{3j}}$ with BDT score $\in [0.88, 1.0]$. All of the considered production modes ($\widetilde{\chi}_{2}^{0}\widetilde{\chi}_{1}^{\pm}$, $\widetilde{\chi}_{1}^{\pm}\widetilde{\chi}_{1}^{\mp}$, $\widetilde{\chi}_{2}^{0}\widetilde{\chi}_{2}^{0}$, and $\widetilde{\chi}_{1}^{\pm}\widetilde{\chi}_{1}^{\pm}$) are included. The efficiency is defined by the number of events of reconstructed-level signal simulation divided by the number of events obtained at generator level. The generator-level selections are the same as the ones at reconstruction level.

Event selection cutflows for signal samples with $m(\tilde\chi^0_2) =100~\text{GeV}$ and $\Delta m(\tilde\chi^0_2 / \tilde\chi^\pm_1,\tilde\chi^0_1) = 0.2~\text{GeV}, 1.0~\text{GeV},$ and $5.0~\text{GeV}$. The first number in the column for each mass point corresponds to the signal event yield after applying the associated cut while the second number in parentheses represents the efficiency with respect to the previous cut. All of the production modes are included. The total cross-section used to obtain the initial number of events ($\sigma$) includes the cuts applied at parton level as described in the main text.

Measured signal strengths $\mu$ and their total uncertainties for different Higgs boson decay channels. The results are shown for the combination of ATLAS and CMS, and separately for each experiment, for the combined $\sqrt{s}$=7 and 8 TeV data. The expected uncertainties in the measurements are also displayed. These results are obtained assuming that the Higgs boson production process cross sections at $\sqrt{s}$ = 7 and 8 TeV are the same as in the SM.

Summary of fit results for a parameterisation probing the ratios of coupling modifiers for leptons versus quarks. The results for the combination of ATLAS and CMS are reported together with their measured and expected uncertainties. Also shown are the results from each experiment. The parameter $\kappa_{qq}$ is positive definite since $\kappa_H$ is always assumed to be positive. For the parameter $\lambda_{lq}$, for which there is no sensitivity to the sign, only the absolute values are shown. Negative values for the parameter $\lambda_{Vq}$ are excluded by more than 4$\sigma$.

Correlation matrix obtained from the fit combining the ATLAS and CMS data using the generic parameterisation with 23 parameters, $\sigma_i\cdot\mathrm{B}^f$ for each specific channel $i\to H\to f$. Only 20 parameters are shown because the other three, corresponding to the $H\to ZZ$ decay channel for the $WH$, $ZH$, and $ttH$ production processes, are not measured with a meaningful precision.

Expected correlation matrix obtained from the fit combining ATLAS and CMS pre-fit Asimov data sets using the generic parameterisation with 23 parameters, $\sigma_i\cdot\mathrm{B}^f$ for each specific channel $i\to H\to f$. Only 20 parameters are shown because the other three, corresponding to the $H\to ZZ$ decay channel for the $WH$, $ZH$, and $ttH$ production processes, are not measured with a meaningful precision.

Expected correlation matrix obtained from the fit combining ATLAS and CMS pre-fit Asimov data sets using the generic parameterisation with nine parameters, $\sigma(gg\to H\to ZZ)$, $\sigma_i/\sigma_{gg\mathrm{F}}$, and $\mathrm{B}^f/\mathrm{B}^{ZZ}$.

Observed and expected upper limits at 95% CL on the inclusive ggF and VBF HH production cross-section from the bb̄τ⁺τ^-, bb̄γγ, bb̄bb̄, multilepton and bb̄ℓℓ+E_T^miss decay channels, and their statistical combination. The Higgs boson mass is set to 125 GeV when deriving the predicted SM cross-section (red band). The expected limits, along with the ±1σ and ±2σ bands, are calculated under the assumption of no Higgs boson pair production and with all NPs profiled to the observed data.

Observed value of the test statistic (-2ln$\Lambda$), as a function of the $\kappa_\lambda$ parameter for combination.

Observed (solid lines) and expected (dashed lines) 95% CL exclusion limits on the HH production cross-sections of (a) the inclusive ggF and VBF processes as a function of κ_λ, for the bb̄γγ (purple), bb̄τ⁺τ^- (green), multilepton (cyan), bb̄bb̄ (blue) and bb̄ℓℓ+E_T^miss (brown) decay channels and their combination (black). The expected limits assume no HH production. The red line shows the theory prediction for the ggF and VBF HH production cross-section as a function of κ_λ. The bands surrounding the red cross-section lines indicate the theoretical uncertainties on the predicted cross-section.

Observed (solid lines) and expected (dashed lines) 95% CL exclusion limits on the HH production cross-sections of the VBF process as a function of κ_2V, for the bb̄γγ (purple), bb̄τ⁺τ^- (green), multilepton (cyan), bb̄bb̄ (blue) and bb̄ℓℓ+E_T^miss (brown) decay channels and their combination (black). The expected limits assume no VBF HH production. The ggF HH production cross-section is assumed to be as predicted by the SM. The ggF HH production cross-section is assumed to be as predicted by the SM. The red line shows the predicted VBF HH cross-section as a function of κ_2V. The bands surrounding the red cross-section lines indicate the theoretical uncertainties on the predicted cross-section.