Observed and expected distributions of the invariant mass of the four-lepton system in the $A\to ZH\to 4\ell+X$ search for SR1 under a background-only fit to data. The total background includes the $q\overline{q}\to ZZ$, $gg\to ZZ$, $q\overline{q}\to ZZ$ (EW), $VVV$, $t\overline{t}V$, $t\overline{t}$, $Z$+jets and $WZ$ processes. The distribution of the $(m_{A}, m_{H}) = (510, 380)$ GeV signal is normalised to the observed upper limit on the cross-section (29.9 fb).

Observed and expected distributions of the invariant mass of the four-lepton system in the $A\to ZH\to 4\ell+X$ search for SR2 under a background-only fit to data. The total background includes the $q\overline{q}\to ZZ$, $gg\to ZZ$, $q\overline{q}\to ZZ$ (EW), $VVV$, $t\overline{t}V$, $t\overline{t}$, $Z$+jets and $WZ$ processes. The distribution of the $(m_{A}, m_{H}) = (510, 380)$ GeV signal is normalised to the observed upper limit on the cross-section (29.9 fb).

Observed and expected distributions of the invariant mass of the four-lepton system in the $A\to ZH\to 4\ell+X$ search for SR3 under a background-only fit to data. The total background includes the $q\overline{q}\to ZZ$, $gg\to ZZ$, $q\overline{q}\to ZZ$ (EW), $VVV$, $t\overline{t}V$, $t\overline{t}$, $Z$+jets and $WZ$ processes. The distribution of the $(m_{A}, m_{H}) = (510, 380)$ GeV signal is normalised to the observed upper limit on the cross-section (29.9 fb).

Observed and expected distributions of the invariant mass of the four-lepton system in the $A\to ZH\to 4\ell+X$ search for SR4 under a background-only fit to data. The total background includes the $q\overline{q}\to ZZ$, $gg\to ZZ$, $q\overline{q}\to ZZ$ (EW), $VVV$, $t\overline{t}V$, $t\overline{t}$, $Z$+jets and $WZ$ processes. The distribution of the $(m_{A}, m_{H}) = (510, 380)$ GeV signal is normalised to the observed upper limit on the cross-section (29.9 fb).

Observed and expected distributions of the invariant mass of the four-lepton system in the $A\to ZH\to 4\ell+X$ search for SR5 under a background-only fit to data. The total background includes the $q\overline{q}\to ZZ$, $gg\to ZZ$, $q\overline{q}\to ZZ$ (EW), $VVV$, $t\overline{t}V$, $t\overline{t}$, $Z$+jets and $WZ$ processes. The distribution of the $(m_{A}, m_{H}) = (510, 380)$ GeV signal is normalised to the observed upper limit on the cross-section (29.9 fb).

Observed and expected distributions of the invariant mass of the four-lepton system in the $A\to ZH\to 4\ell+X$ search for SR6 under a background-only fit to data. The total background includes the $q\overline{q}\to ZZ$, $gg\to ZZ$, $q\overline{q}\to ZZ$ (EW), $VVV$, $t\overline{t}V$, $t\overline{t}$, $Z$+jets and $WZ$ processes. The distribution of the $(m_{A}, m_{H}) = (510, 380)$ GeV signal is normalised to the observed upper limit on the cross-section (29.9 fb).

Observed and expected distributions of the invariant mass of the four-lepton system in the $A\to ZH\to 4\ell+X$ search for SR7 under a background-only fit to data. The total background includes the $q\overline{q}\to ZZ$, $gg\to ZZ$, $q\overline{q}\to ZZ$ (EW), $VVV$, $t\overline{t}V$, $t\overline{t}$, $Z$+jets and $WZ$ processes. The distribution of the $(m_{A}, m_{H}) = (510, 380)$ GeV signal is normalised to the observed upper limit on the cross-section (29.9 fb).

Local p0-values in the $(m_{H}, m_{R})$ plane for the $R\to SH\to 4\ell+E^{\textrm{miss}}_{\textrm{T}}$ search with $m_{S} = 160$ GeV.

Local p0-values in the $(m_{H}, m_{A})$ plane for the $A\to ZH\to 4\ell+X$ search.

The observed upper limits at 95% confidence level on $\sigma(gg\to R)\times \mathcal{B}(R\to SH)\times (H\to ZZ)$ across the $(m_{H}, m_{R})$ plane with $m_{S} = 160$ GeV for the $R\to SH\to 4\ell+E^{\textrm{miss}}_{\textrm{T}}$ search.

The expected upper limits at 95% confidence level on $\sigma(gg\to R)\times \mathcal{B}(R\to SH)\times (H\to ZZ)$ across the $(m_{H}, m_{R})$ plane with $m_{S} = 160$ GeV for the $R\to SH\to 4\ell+E^{\textrm{miss}}_{\textrm{T}}$ search.

The observed upper limits at 95% confidence level on $\sigma(gg\to A)\times \mathcal{B}(A\to ZH)\times (H\to ZZ)$ across the $(m_{H}, m_{A})$ plane for the $A\to ZH\to 4\ell+X$ search.

The expected upper limits at 95% confidence level on $\sigma(gg\to A)\times \mathcal{B}(A\to ZH)\times (H\to ZZ)$ across the $(m_{H}, m_{A})$ plane for the $A\to ZH\to 4\ell+X$ search.

Cut-flow of the raw events at each selection stage for the $R\rightarrow SH\rightarrow 4\ell + E^{\textrm{miss}}_{\textrm{T}}$ signal with a mass point of $(m_R, m_H ) = (390, 220)$ GeV and $m_S = 160$ GeV. The events are shown for the individual and combined four-lepton channels. The SFOS denotes same flavour and opposite sign lepton pairs selection and the final selection is shown for each signal region. The final selection criteria for SR1 to SR3 are defined in Table 2 of the paper.

Cut-flow of the raw events at each selection stage for the $A\rightarrow Z(\rightarrow jj/\ell^+\ell^-/\textrm{invisible})H(\rightarrow 4\ell)$ signal with a mass point of $(m_A, m_H ) = (330, 220)$ GeV. The events are shown for the individual and combined four-lepton channels. The SFOS denotes same flavour and opposite sign lepton pairs selection and the final selection is shown for each signal region. The final selection criteria for SR1 to SR7 are defined in Table 2 of the paper.

Cut-flow of the raw events at each selection stage for the $A\rightarrow Z(\rightarrow 2\ell)H(\rightarrow 2\ell+jj/\textrm{invisible})$ signal with a mass point of $(m_A, m_H ) = (330, 220)$ GeV. The events are shown for the individual and combined four-lepton channels. The SFOS denotes same flavour and opposite sign lepton pairs selection and the final selection is shown for each signal region. The final selection criteria for SR1 to SR7 are defined in Table 2 of the paper.

Distribution of the four-lepton invariant mass in the four-lepton final state for the ggF-MVA-low category.

Distribution of the four-lepton invariant mass in the four-lepton final state for the VBF-MVA-enriched category.

Distribution of the transverse mass in the llvv final state for the ggF-enriched eevv category.

Distribution of the transverse mass in the llvv final state for the ggF-enriched mumuvv category.

Distribution of the transverse mass in the llvv final state for the VBF-enriched eevv category.

Distribution of the transverse mass in the llvv final state for the VBF-enriched mumuvv category.

The upper limits at 95% CL on the cross section times branching ratio as a function of the heavy resonance mass for the ggF production mode

The upper limits at 95% CL on the cross section times branching ratio as a function of the heavy resonance mass for the VBF production mode

The upper limits at 95% CL on the cross section for the ggF production mode times branching ratio as a function of the heavy resonance mass for an additional heavy scalar assuming a width of 1% of its mass

The upper limits at 95% CL on the cross section for the ggF production mode times branching ratio as a function of the heavy resonance mass for an additional heavy scalar assuming a width of 5% of its mass

The upper limits at 95% CL on the cross section for the ggF production mode times branching ratio as a function of the heavy resonance mass for an additional heavy scalar assuming a width of 10% of its mass

The upper limits at 95% CL on the cross section for the ggF production mode times branching ratio as a function of the heavy resonance mass for an additional heavy scalar assuming a width of 15% of its mass

The upper limits at 95% CL on the cross section times branching ratio for a KK graviton produced with k/M_{PI} = 1

Measured and expected differential cross-section $\text{d}\sigma / \text{d} m_{4l}$ as a function of $m_{4l}$ in bin of 50$< p_{T}^{4l} <$100 GeV

Measured and expected differential cross-section $\text{d}\sigma / \text{d} m_{4l}$ as a function of $m_{4l}$ in bin of 100$< p_{T}^{4l} <$600 GeV

Measured and expected double differential cross-section $\text{d}\sigma / \text{d} m_{4l}$ as a function of $m_{4l}$ in bin of 0.0$< y_{4l} <$0.4

Measured and expected double differential cross-section $\text{d}\sigma / \text{d} m_{4l}$ as a function of $m_{4l}$ in bin of 0.4$< y_{4l} <$0.8

Measured and expected double differential cross-section $\text{d}\sigma / \text{d} m_{4l}$ as a function of $m_{4l}$ in bin of 0.8$< y_{4l} <$1.2

Measured and expected double differential cross-section $\text{d}\sigma / \text{d} m_{4l}$ as a function of $m_{4l}$ in bin of 1.2$< y_{4l} <$2.5

Measured and expected double differential cross-section $\text{d}\sigma / \text{d} m_{4l}$ as a function of $m_{4l}$ for MELA$<$1.4 bin

Measured and expected double differential cross-section $\text{d}\sigma / \text{d} m_{4l}$ as a function of $m_{4l}$ for MELA$>$1.4 bin

Measured and expected double differential cross-section $\text{d}\sigma / \text{d} m_{4l}$ as a function of $m_{4l}$ for $\mu\mu\mu\mu$ events

Measured and expected double differential cross-section $\text{d}\sigma / \text{d} m_{4l}$ as a function of $m_{4l}$ for $eeee$ events

Measured and expected double differential cross-section $\text{d}\sigma / \text{d} m_{4l}$ as a function of $m_{4l}$ for $ee\mu\mu$ events

Systematic covariance matrix for the differential $m_{4l}$ distribution.

Statistical covariance matrix for the differential $m_{4l}$ distribution.

Background covariance matrix for the differential $m_{4l}$ distribution.

Systematic covariance matrix for the differential $m_{4l}$-$p_{T}^{4l}$ distribution.<br><br> Bins labelled 1-9 correspond to the 0$< p_{T}^{4l} < $20 GeV bin with $m_{4l}$ values as listed in Table 2.<br> Bins labelled 10-16 correspond to the 20$< p_{T}^{4l} <$50 GeV bin with $m_{4l}$ values as listed in Table 3.<br> Bins labelled 17-23 correspond to the 50$< p_{T}^{4l} <$100 GeV bin with $m_{4l}$ values as listed in Table 4.<br> Bins labelled 24-30 correspond to the 100$< p_{T}^{4l} <$600 GeV bin with $m_{4l}$ values as listed in Table 5.

Statistical covariance matrix for the differential $m_{4l}$-$p_{T}^{4l}$ distribution. <br><br> Bins labelled 1-9 correspond to the 0$< p_{T}^{4l} < $20 GeV bin with $m_{4l}$ values as listed in Table 2.<br> Bins labelled 10-16 correspond to the 20$< p_{T}^{4l} <$50 GeV bin with $m_{4l}$ values as listed in Table 3.<br> Bins labelled 17-23 correspond to the 50$< p_{T}^{4l} <$100 GeV bin with $m_{4l}$ values as listed in Table 4.<br> Bins labelled 24-30 correspond to the 100$< p_{T}^{4l} <$600 GeV bin with $m_{4l}$ values as listed in Table 5.

Background covariance matrix for the differential $m_{4l}$-$p_{T}^{4l}$ distribution. <br><br> Bins labelled 1-9 correspond to the 0$< p_{T}^{4l} < $20 GeV bin with $m_{4l}$ values as listed in Table 2.<br> Bins labelled 10-16 correspond to the 20$< p_{T}^{4l} <$50 GeV bin with $m_{4l}$ values as listed in Table 3.<br> Bins labelled 17-23 correspond to the 50$< p_{T}^{4l} <$100 GeV bin with $m_{4l}$ values as listed in Table 4.<br> Bins labelled 24-30 correspond to the 100$< p_{T}^{4l} <$600 GeV bin with $m_{4l}$ values as listed in Table 5.

Systematic covariance matrix for the differential $m_{4l}$-$y_{4l}$ distribution. <br><br> Bins labelled 1-9 correspond to the 0.0$< y_{4l} < $0.4 bin with $m_{4l}$ values as listed in Table 6.<br> Bins labelled 10-18 correspond to the 0.4$< y_{4l} <$0.8 bin with $m_{4l}$ values as listed in Table 7.<br> Bins labelled 19-26 correspond to the 0.8$< y_{4l} <$1.2 bin with $m_{4l}$ values as listed in Table 8.<br> Bins labelled 27-34 correspond to the 1.2$< y_{4l} <$2.5 bin with $m_{4l}$ values as listed in Table 9.

Statistical covariance matrix for the differential $m_{4l}$-$y_{4l}$ distribution. <br><br> Bins labelled 1-9 correspond to the 0.0$< y_{4l} < $0.4 bin with $m_{4l}$ values as listed in Table 6.<br> Bins labelled 10-18 correspond to the 0.4$< y_{4l} <$0.8 bin with $m_{4l}$ values as listed in Table 7.<br> Bins labelled 19-26 correspond to the 0.8$< y_{4l} <$1.2 bin with $m_{4l}$ values as listed in Table 8.<br> Bins labelled 27-34 correspond to the 1.2$< y_{4l} <$2.5 bin with $m_{4l}$ values as listed in Table 9.

Background covariance matrix for the differential $m_{4l}$-$y_{4l}$ distribution. <br><br> Bins labelled 1-9 correspond to the 0.0$< y_{4l} < $0.4 bin with $m_{4l}$ values as listed in Table 6.<br> Bins labelled 10-18 correspond to the 0.4$< y_{4l} <$0.8 bin with $m_{4l}$ values as listed in Table 7.<br> Bins labelled 19-26 correspond to the 0.8$< y_{4l} <$1.2 bin with $m_{4l}$ values as listed in Table 8.<br> Bins labelled 27-34 correspond to the 1.2$< y_{4l} <$2.5 bin with $m_{4l}$ values as listed in Table 9.

Systematic covariance matrix for the differential $m_{4l}$-MELA distribution. <br><br> Bins labelled 1-7 correspond to the MELA$<$ 0.4 bin with $m_{4l}$ values as listed in Table 10.<br> Bins labelled 8-12 correspond to the MELA$>$ 0.4 bin with $m_{4l}$ values as listed in Table 11.

Statistical covariance matrix for the differential $m_{4l}$-MELA distribution. <br><br> Bins labelled 1-7 correspond to the MELA$<$ 0.4 bin with $m_{4l}$ values as listed in Table 10.<br> Bins labelled 8-12 correspond to the MELA$>$ 0.4 bin with $m_{4l}$ values as listed in Table 11.

Background covariance matrix for the differential $m_{4l}$-MELA distribution. <br><br> Bins labelled 1-7 correspond to the MELA$<$ 0.4 bin with $m_{4l}$ values as listed in Table 10.<br> Bins labelled 8-12 correspond to the MELA$>$ 0.4 bin with $m_{4l}$ values as listed in Table 11.

Systematic covariance matrix for the differential $m_{4l}$-lepton flavour distribution. <br><br> Bins labelled 1-9 correspond to $\mu\mu\mu\mu$ events with $m_{4l}$ values as listed in Table 12.<br> Bins labelled 10-18 correspond to $eeee$ events with $m_{4l}$ values as listed in Table 13.<br> Bins labelled 19-27 correspond to $\mu\mu\mu\mu$ events with $m_{4l}$ values as listed in Table 14.<br>

Statistical covariance matrix for the differential $m_{4l}$-lepton flavour distribution. <br><br> Bins labelled 1-9 correspond to $\mu\mu\mu\mu$ events with $m_{4l}$ values as listed in Table 12.<br> Bins labelled 10-18 correspond to $eeee$ events with $m_{4l}$ values as listed in Table 13.<br> Bins labelled 19-27 correspond to $\mu\mu\mu\mu$ events with $m_{4l}$ values as listed in Table 14.<br>

Background covariance matrix for the differential $m_{4l}$-lepton flavour distribution. <br><br> Bins labelled 1-9 correspond to $\mu\mu\mu\mu$ events with $m_{4l}$ values as listed in Table 12.<br> Bins labelled 10-18 correspond to $eeee$ events with $m_{4l}$ values as listed in Table 13.<br> Bins labelled 19-27 correspond to $\mu\mu\mu\mu$ events with $m_{4l}$ values as listed in Table 14.<br>