Version 2
Search for dark matter in association with an energetic photon in $pp$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
JHEP 02 (2021) 226, 2021.
Inspire Record 1829872 DOI 10.17182/hepdata.96846

A search for dark matter is conducted in final states containing a photon and missing transverse momentum in proton$-$proton collisions at $\sqrt{s}$ = 13 TeV. The data, collected during 2015$-$2018 by the ATLAS experiment at the CERN LHC, correspond to an integrated luminosity of 139 fb$^{-1}$. No deviations from the predictions of the Standard Model are observed and 95% confidence-level upper limits between 2.45 fb and 0.5 fb are set on the visible cross section for contributions from physics beyond the Standard Model, in different ranges of the missing transverse momentum. The results are interpreted as 95% confidence-level limits in models where weakly interacting dark-matter candidates are pair-produced via an s-channel axial-vector or vector mediator. Dark-matter candidates with masses up to 415 (580) GeV are excluded for axial-vector (vector) mediators, while the maximum excluded mass of the mediator is 1460 (1470) GeV. In addition, the results are expressed in terms of 95% confidence-level limits on the parameters of a model with an axion-like particle produced in association with a photon, and are used to constrain the coupling $g_{aZ\gamma}$ of an axion-like particle to the electroweak gauge bosons.

60 data tables

Distribution of $E^{miss}_T$ in data and for the expected SM background in the SRs after performing the 'simplified shape fit'. The error bars are statistical, and the dashed band includes statistical and systematic uncertainties determined by the fit. The expectations for the simplified model for two different values of $m_{\chi}$ and $m_{med}$, and with $g_{q}=0.25$ and $g_{\chi}=1.0$ and for the ALP model are also shown. The lower panel shows the ratio of data to expected background event yields.

Distribution of $E^{miss}_T$ in data and for the expected SM background in the SRs after performing the 'simplified shape fit'. Overflows are included in the fourth bin of each distribution. The error bars are statistical, and the dashed band includes statistical and systematic uncertainties determined by the fit. The expectations for the simplified model for two different values of $m_{\chi}$ and $m_{med}$, and with $g_{q}=0.25$ and $g_{\chi}=1.0$ and for the ALP model are also shown. The lower panel shows the ratio of data to expected background event yields.

Distribution of $E^{miss}_T$ in data and for the expected SM background in the Single-Muon CR after performing the 'simplified shape fit'. The $E^{miss}_T$ calculation in this CR does not include the muon contribution. The error bars are statistical, and the dashed band includes statistical and systematic uncertainties determined by the fit. The lower panel shows the ratio of data to expected background event yields.

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Version 2
Search for squarks and gluinos in final states with jets and missing transverse momentum using 139 fb$^{-1}$ of $\sqrt{s}$ =13 TeV $pp$ collision data with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
JHEP 02 (2021) 143, 2021.
Inspire Record 1827025 DOI 10.17182/hepdata.95664

A search for the supersymmetric partners of quarks and gluons (squarks and gluinos) in final states containing jets and missing transverse momentum, but no electrons or muons, is presented. The data used in this search were recorded by the ATLAS experiment in proton-proton collisions at a centre-of-mass energy of $\sqrt{s}$ = 13 TeV during Run 2 of the Large Hadron Collider, corresponding to an integrated luminosity of 139 fb$^{-1}$. The results are interpreted in the context of various $R$-parity-conserving models where squarks and gluinos are produced in pairs or in association and a neutralino is the lightest supersymmetric particle. An exclusion limit at the 95% confidence level on the mass of the gluino is set at 2.30 TeV for a simplified model containing only a gluino and the lightest neutralino, assuming the latter is massless. For a simplified model involving the strong production of mass-degenerate first- and second-generation squarks, squark masses below 1.85 TeV are excluded if the lightest neutralino is massless. These limits extend substantially beyond the region of supersymmetric parameter space excluded previously by similar searches with the ATLAS detector.

150 data tables

Observed $m_{\mathrm{eff}}$ distributions in signal regions MB-SSd. The histograms show the MC background predictions normalised by the background-only fit. The hatched (red) error bands indicate experimental and MC statistical uncertainties. Expected distributions for benchmark signal model points, normalised using the approximate NNLO+NNLL cross-section times integrated luminosity, are also shown for comparison (masses in GeV).

Observed $m_{\mathrm{eff}}$ distributions in signal regions MB-SSd. The histograms show the MC background predictions normalised by the background-only fit. The hatched (red) error bands indicate experimental and MC statistical uncertainties. Expected distributions for benchmark signal model points, normalised using the approximate NNLO+NNLL cross-section times integrated luminosity, are also shown for comparison (masses in GeV).

Observed metSig distributions in signal regions MB-SSd. The histograms show the MC background predictions normalised by the background-only fit. The hatched (red) error bands indicate experimental and MC statistical uncertainties. Expected distributions for benchmark signal model points, normalised using the approximate NNLO+NNLL cross-section times integrated luminosity, are also shown for comparison (masses in GeV).

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Search for Higgs boson production in association with a high-energy photon via vector-boson fusion with decay into bottom quark pairs at $\sqrt{s}$=13 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abbott, Brad ; et al.
JHEP 03 (2021) 268, 2021.
Inspire Record 1826521 DOI 10.17182/hepdata.100160

A search is presented for the production of the Standard Model Higgs boson in association with a high-energy photon. With a focus on the vector-boson fusion process and the dominant Higgs boson decay into $b$-quark pairs, the search benefits from a large reduction of multijet background compared to more inclusive searches. Results are reported from the analysis of 132 fb$^{-1}$ of $pp$ collision data at $\sqrt{s}$=13 TeV collected with the ATLAS detector at the LHC. The measured Higgs boson signal yield in this final-state signature is $1.3 \pm 1.0$ times the Standard Model prediction. The observed significance of the Higgs boson signal above the background is 1.3 standard deviations, compared to an expected significance of 1.0 standard deviations.

13 data tables

Comparisons of data and simulated event distributions of the BDT input variable \(\Delta \eta_{jj}\) in the two \(m_{bb}\) sidebands after kinematic reweighting of the non-resonant \(b\bar{b}\gamma jj\) background. The data are shown as black points, and the background contributions are stacked in coloured histograms. The Higgs boson signal contribution is scaled up and represented by the dashed red line. The bottom panel in each plot shows the ratio of the data to the SM prediction, where the uncertainty band corresponds to the statistical uncertainty only.

Comparisons of data and simulated event distributions of the BDT input variable \(p_{\text{T}}^{\text{balance}}\) in the two \(m_{bb}\) sidebands after kinematic reweighting of the non-resonant \(b\bar{b}\gamma jj\) background. The data are shown as black points, and the background contributions are stacked in coloured histograms. The Higgs boson signal contribution is scaled up and represented by the dashed red line. The bottom panel in each plot shows the ratio of the data to the SM prediction, where the uncertainty band corresponds to the statistical uncertainty only.

The \(m_{bb}\) distributions in the HighBDT categories, overlaid with contributions from the \(H\gamma jj\) signal as well as the resonant \(Z\gamma jj\) and non-resonant \(b\bar{b} \gamma jj\) background fits. The combined \(\chi^2\) per degree of freedom is \(45.2/45\). The bottom panel in each plot presents the significance of the Higgs boson signal relative to the non-resonant \(b\bar{b} \gamma jj\) background in each bin.

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Search for dark matter produced in association with a dark Higgs boson decaying into $W^\pm W^\mp$ or $ZZ$ in fully hadronic final states from $\sqrt{s}=13$ TeV $pp$ collisions recorded with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Phys.Rev.Lett. 126 (2021) 121802, 2021.
Inspire Record 1822529 DOI 10.17182/hepdata.97191

Several extensions of the Standard Model predict the production of dark matter particles at the LHC. An uncharted signature of dark matter particles produced in association with $VV=W^\pm W^\mp$ or $ZZ$ pairs from a decay of a dark Higgs boson $s$ is searched for using 139 fb$^{-1}$ of $pp$ collisions recorded by the ATLAS detector at a center-of-mass energy of 13 TeV. The $s\to V(q\bar q)V(q\bar q)$ decays are reconstructed with a novel technique aimed at resolving the dense topology from boosted $VV$ pairs using jets in the calorimeter and tracking information. Dark Higgs scenarios with $m_s > 160$ GeV are excluded.

13 data tables

Data overlaid on SM background post-fit yields stacked in each SR and CR category and E<sub>T</sub><sup>miss</sup> bin with the maximum-likelihood estimators set to the conditional values of the CR-only fit, and propagated to SR and CRs. Pre-fit uncertainties cover differences between the data and pre-fit background prediction.

Dominant sources of uncertainty for three dark Higgs scenarios after the fit to Asimov data generated from the expected values of the maximum-likelihood estimators including predicted signals with m<sub>Z'</sub> = 1 TeV and m<sub>s</sub> of (a) 160 GeV, (b) 235 GeV, and (c) 310 GeV. The uncertainty in the fitted signal yield relative to the theory prediction is presented. Total is the quadrature sum of statistical and total systematic uncertainties, which consider correlations.

The ratios (&mu;) of the 95&#37; C.L. upper limits on the combined s&rarr; W<sup>&plusmn;</sup>W<sup>&#8723;</sup> and s&rarr; ZZ cross section to simplified model expectations for the m<sub>Z'</sub>=0.5 TeV scenario, for various m<sub>s</sub> hypotheses. The observed limits (solid line) are consistent with the expectation under the SM-only hypothesis (dashed line) within uncertainties (filled band), except for a small excess for m<sub>s</sub>=160 GeV, discussed in the text.

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Search for charged-lepton-flavour violation in $Z$-boson decays with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Nature Phys. 17 (2021) 819 819-825, 2021.
Inspire Record 1821688 DOI 10.17182/hepdata.96390

The ATLAS experiment at the Large Hadron Collider reports a search for charged-lepton-flavour violation in decays of $Z$ bosons into a τ lepton and an electron or muon of opposite charge.

9 data tables

The best-fit expected and observed distributions of the combined NN output in the CRZ$\tau\tau$ for the $\mu\tau$ channel for events with 1-prong $\tau_\text{had-vis}$ candidates. The last bin in each plot includes overflow events.

The best-fit expected and observed distributions of the combined NN output in the CRZ$\tau\tau$ for the $\mu\tau$ channel for events with 3-prong $\tau_\text{had-vis}$ candidates. The last bin in each plot includes overflow events.

The best-fit expected and observed distributions of the combined NN output in the VRSS for the $e\tau$ channel for events with 1-prong $\tau_\text{had-vis}$ candidates. The last bin in each plot includes overflow events.

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Search for pair production of scalar leptoquarks decaying into first- or second-generation leptons and top quarks in proton-proton collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Eur.Phys.J.C 81 (2021) 313, 2021.
Inspire Record 1821703 DOI 10.17182/hepdata.96389

A search for pair production of scalar leptoquarks, each decaying into either an electron or a muon and a top quark, is presented. This is the first leptoquark search using ATLAS data to investigate top-philic cross-generational couplings that could provide explanations for recently observed anomalies in $B$ meson decays. This analysis targets high leptoquark masses which cause the decay products of each resultant top quark to be contained within a single high-$p_{\mathrm{T}}$ large-radius jet. The full Run 2 dataset is exploited, consisting of 139 fb$^{-1}$ of data collected from proton-proton collisions at $\sqrt{s}=13$ TeV from 2015 to 2018 with the ATLAS detector at the CERN Large Hadron Collider. In the absence of any significant deviation from the background expectation, lower limits on the leptoquark masses are set at 1480 GeV and 1470 GeV for the electron and muon channel, respectively.

4 data tables

Expected and observed upper limits at the 95% CL on the leptoquark pair production cross section as a function of leptoquark mass under the assumption of $\mathcal{B}$(LQ->$te$)=1.

Expected and observed upper limits at the 95% CL on the leptoquark pair production cross section as a function of leptoquark mass under the assumption of $\mathcal{B}$(LQ->$t\mu$)=1.

Expected and observed 95% CL lower limits on the leptoquark mass as a function of the branching ratio $\mathcal{B}$(LQ->$te$).

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Search for phenomena beyond the Standard Model in events with large $b$-jet multiplicity using the ATLAS detector at the LHC

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Eur.Phys.J.C 81 (2021) 11, 2021.
Inspire Record 1821239 DOI 10.17182/hepdata.95683

A search is presented for new phenomena in events characterised by high jet multiplicity, no leptons (electrons or muons), and four or more jets originating from the fragmentation of $b$-quarks ($b$-jets). The search uses 139 fb$^{-1}$ of $\sqrt{s}$ = 13 TeV proton-proton collision data collected by the ATLAS experiment at the Large Hadron Collider during Run 2. The dominant Standard Model background originates from multijet production and is estimated using a data-driven technique based on an extrapolation from events with low $b$-jet multiplicity to the high $b$-jet multiplicities used in the search. No significant excess over the Standard Model expectation is observed and 95% confidence-level limits that constrain simplified models of R-parity-violating supersymmetry are determined. The exclusion limits reach 950 GeV in top-squark mass in the models considered.

49 data tables

<b>- - - - - - - - Overview of HEPData Record - - - - - - - -</b> <br><br> <b>Exclusion contours:</b> <ul> <li><a href="?table=stbchionly_obs">Stop to bottom quark and chargino exclusion contour (Obs.)</a> <li><a href="?table=stbchionly_exp">Stop to bottom quark and chargino exclusion contour (Exp.)</a> <li><a href="?table=stbchi_obs">Stop to higgsino LSP exclusion contour (Obs.)</a> <li><a href="?table=stbchi_exp">Stop to higgsino LSP exclusion contour (Exp.)</a> <li><a href="?table=sttN_obs">Stop to top quark and neutralino exclusion contour (Obs.)</a> <li><a href="?table=sttN_exp">Stop to top quark and neutralino exclusion contour (Exp.)</a> </ul> <b>Upper limits:</b> <ul> <li><a href="?table=stbchionly_xSecUL_obs">Obs Xsection upper limit in stop to bottom quark and chargino</a> <li><a href="?table=stop_xSecUL_obs">Obs Xsection upper limit in higgsino LSP</a> <li><a href="?table=stbchionly_xSecUL_exp">Exp Xsection upper limit in stop to bottom quark and chargino</a> <li><a href="?table=stop_xSecUL_exp">Exp Xsection upper limit in higgsino LSP</a> </ul> <b>Kinematic distributions:</b> <ul> <li><a href="?table=SR_yields">SR_yields</a> </ul> <b>Cut flows:</b> <ul> <li><a href="?table=cutflow">cutflow</a> </ul> <b>Acceptance and efficiencies:</b> As explained in <a href="https://twiki.cern.ch/twiki/bin/view/AtlasPublic/SupersymmetryPublicResults#summary_of_auxiliary_material">the twiki</a>. <ul> <li> <b>stbchi_6je4be:</b> <a href="?table=stbchi_Acc_6je4be">stbchi_Acc_6je4be</a> <a href="?table=stbchi_Eff_6je4be">stbchi_Eff_6je4be</a> <li> <b>stbchi_7je4be:</b> <a href="?table=stbchi_Acc_7je4be">stbchi_Acc_7je4be</a> <a href="?table=stbchi_Eff_7je4be">stbchi_Eff_7je4be</a> <li> <b>stbchi_8je4be:</b> <a href="?table=stbchi_Acc_8je4be">stbchi_Acc_8je4be</a> <a href="?table=stbchi_Eff_8je4be">stbchi_Eff_8je4be</a> <li> <b>stbchi_9ji4be:</b> <a href="?table=stbchi_Acc_9ji4be">stbchi_Acc_9ji4be</a> <a href="?table=stbchi_Eff_9ji4be">stbchi_Eff_9ji4be</a> <li> <b>stbchi_6je5bi:</b> <a href="?table=stbchi_Acc_6je5bi">stbchi_Acc_6je5bi</a> <a href="?table=stbchi_Eff_6je5bi">stbchi_Eff_6je5bi</a> <li> <b>stbchi_7je5bi:</b> <a href="?table=stbchi_Acc_7je5bi">stbchi_Acc_7je5bi</a> <a href="?table=stbchi_Eff_7je5bi">stbchi_Eff_7je5bi</a> <li> <b>stbchi_8je5bi:</b> <a href="?table=stbchi_Acc_8je5bi">stbchi_Acc_8je5bi</a> <a href="?table=stbchi_Eff_8je5bi">stbchi_Eff_8je5bi</a> <li> <b>stbchi_9ji5bi:</b> <a href="?table=stbchi_Acc_9ji5bi">stbchi_Acc_9ji5bi</a> <a href="?table=stbchi_Eff_9ji5bi">stbchi_Eff_9ji5bi</a> <li> <b>stbchi_8ji5bi:</b> <a href="?table=stbchi_Acc_8ji5bi">stbchi_Acc_8ji5bi</a> <a href="?table=stbchi_Eff_8ji5bi">stbchi_Eff_8ji5bi</a> <li> <b>sttN_6je4be:</b> <a href="?table=sttN_Acc_6je4be">sttN_Acc_6je4be</a> <a href="?table=sttN_Eff_6je4be">sttN_Eff_6je4be</a> <li> <b>sttN_7je4be:</b> <a href="?table=sttN_Acc_7je4be">sttN_Acc_7je4be</a> <a href="?table=sttN_Eff_7je4be">sttN_Eff_7je4be</a> <li> <b>sttN_8je4be:</b> <a href="?table=sttN_Acc_8je4be">sttN_Acc_8je4be</a> <a href="?table=sttN_Eff_8je4be">sttN_Eff_8je4be</a> <li> <b>sttN_9ji4be:</b> <a href="?table=sttN_Acc_9ji4be">sttN_Acc_9ji4be</a> <a href="?table=sttN_Eff_9ji4be">sttN_Eff_9ji4be</a> <li> <b>sttN_6je5bi:</b> <a href="?table=sttN_Acc_6je5bi">sttN_Acc_6je5bi</a> <a href="?table=sttN_Eff_6je5bi">sttN_Eff_6je5bi</a> <li> <b>sttN_7je5bi:</b> <a href="?table=sttN_Acc_7je5bi">sttN_Acc_7je5bi</a> <a href="?table=sttN_Eff_7je5bi">sttN_Eff_7je5bi</a> <li> <b>sttN_8je5bi:</b> <a href="?table=sttN_Acc_8je5bi">sttN_Acc_8je5bi</a> <a href="?table=sttN_Eff_8je5bi">sttN_Eff_8je5bi</a> <li> <b>sttN_9ji5bi:</b> <a href="?table=sttN_Acc_9ji5bi">sttN_Acc_9ji5bi</a> <a href="?table=sttN_Eff_9ji5bi">sttN_Eff_9ji5bi</a> <li> <b>sttN_8ji5bi:</b> <a href="?table=sttN_Acc_8ji5bi">sttN_Acc_8ji5bi</a> <a href="?table=sttN_Eff_8ji5bi">sttN_Eff_8ji5bi</a> </ul> <b>Truth Code snippets</b> and <b>SLHA</a> files are available under "Resources" (purple button on the left)

The observed exclusion contour at 95% CL as a function of the $\it{m}_{\tilde{\chi}^{\pm}_{1}}$ vs. $\it{m}_{\tilde{t}}$. Masses that are within the contours are excluded. Limits are shown for $B(\tilde{t} \rightarrow b \chi^{+}_{1})$ equal to unity.

The expected exclusion contour at 95% CL as a function of the $\it{m}_{\tilde{\chi}^{\pm}_{1}}$ vs. $\it{m}_{\tilde{t}}$. Masses that are within the contour are excluded. Limits are shown for $B(\tilde{t} \rightarrow b \chi^{+}_{1})$ equal to unity.

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Search for heavy resonances decaying into a pair of $Z$ bosons in the $\ell^+\ell^-\ell'^+\ell'^-$ and $\ell^+\ell^-\nu\bar\nu$ final states using 139 fb$^{-1}$ of proton-proton collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abbott, Brad ; et al.
Eur.Phys.J.C 81 (2021) 332, 2021.
Inspire Record 1820316 DOI 10.17182/hepdata.97159

A search for heavy resonances decaying into a pair of $Z$ bosons leading to $\ell^+\ell^-\ell'^+\ell'^-$ and $\ell^+\ell^-\nu\bar\nu$ final states, where $\ell$ stands for either an electron or a muon, is presented. The search uses proton-proton collision data at a centre-of-mass energy of 13 TeV collected from 2015 to 2018 that corresponds to the full integrated luminosity of 139 fb$^{-1}$ recorded by the ATLAS detector during Run 2 of the Large Hadron Collider. Different mass ranges spanning 200 GeV to 2000 GeV for the hypothetical resonances are considered, depending on the final state and model. In the absence of a significant observed excess, the results are interpreted as upper limits on the production cross section of a spin-0 or spin-2 resonance. The upper limits for the spin-0 resonance are translated to exclusion contours in the context of Type-I and Type-II two-Higgs-doublet models, and the limits for the spin-2 resonance are used to constrain the Randall--Sundrum model with an extra dimension giving rise to spin-2 graviton excitations.

16 data tables

Distribution of the four-lepton invariant mass in the four-lepton final state for the ggF-MVA-high 4-muon category.

Distribution of the four-lepton invariant mass in the four-lepton final state for the ggF-MVA-high 2e2mu category.

Distribution of the four-lepton invariant mass in the four-lepton final state for the ggF-MVA-high 4-electron category.

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Observation and measurement of forward proton scattering in association with lepton pairs produced via the photon fusion mechanism at ATLAS

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Phys.Rev.Lett. 125 (2020) 261801, 2020.
Inspire Record 1820312 DOI 10.17182/hepdata.116547

The observation of forward proton scattering in association with lepton pairs ($e^+e^-+p$ or $\mu^+\mu^-+p$) produced via photon fusion is presented. The scattered proton is detected by the ATLAS Forward Proton spectrometer while the leptons are reconstructed by the central ATLAS detector. Proton-proton collision data recorded in 2017 at a center-of-mass energy of $\sqrt{s} = 13$ TeV are analyzed, corresponding to an integrated luminosity of 14.6 fb$^{-1}$. A total of 57 (123) candidates in the $ee+p$ ($\mu\mu+p$) final state are selected, allowing the background-only hypothesis to be rejected with a significance exceeding five standard deviations in each channel. Proton-tagging techniques are introduced for cross-section measurements in the fiducial detector acceptance, corresponding to $\sigma_{ee+p}$ = 11.0 $\pm$ 2.6 (stat.) $\pm$ 1.2 (syst.) $\pm$ 0.3 (lumi.) fb and $\sigma_{\mu\mu+p}$ = 7.2 $\pm$ 1.6 (stat.) $\pm$ 0.9 (syst.) $\pm$ 0.2 (lumi.) fb in the dielectron and dimuon channel, respectively.

1 data table

The measured fiducial cross sections. The first systematic uncertainty is the combined systematic uncertainty excluding luminosity, the second is the luminosity


Search for type-III seesaw heavy leptons in dilepton final states in $pp$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Eur.Phys.J.C 81 (2021) 218, 2021.
Inspire Record 1812090 DOI 10.17182/hepdata.95742

A search for the pair production of heavy leptons as predicted by the type-III seesaw mechanism is presented. The search uses proton-proton collision data at a centre-of-mass energy of 13 TeV, corresponding to 139 fb$^{-1}$ of integrated luminosity recorded by the ATLAS detector during Run 2 of the Large Hadron Collider. The analysis focuses on the final state with two light leptons (electrons or muons) of different flavour and charge combinations, with at least two jets and large missing transverse momentum. No significant excess over the Standard Model expectation is observed. The results are translated into exclusion limits on heavy-lepton masses, and the observed lower limit on the mass of the type-III seesaw heavy leptons is 790 GeV at 95% confidence level.

10 data tables

Cross-sections of the type-III seesaw process for mass points used in the analysis. Branching ratios into at least two leptons are presented with the corresponding effective cross-section.

Expected and observed 95 % CLs exclusion limits for the type-III seesaw process with the corresponding one- and two-standard-deviation bands, showing the 95 % CL upper limit on the cross-section.

Selection efficiencies in percentage relative to the events with at least two leptons for signal mass points used in the analysis. The efficiency is defined as the ratio of expected signal events in a signal region compared with the number of expected events produced, for integrated luminosity 139 fb$^{-1}$.

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