A search for Higgs boson pair production via vector-boson fusion (VBF) in the $b\bar{b}b\bar{b}$ final state is carried out with the ATLAS experiment using 126 fb$^{-1}$ of proton-proton collision data delivered at $\sqrt{s} = 13$ TeV by the Large Hadron Collider. This search is sensitive to VBF production of additional heavy bosons that may decay into Higgs boson pairs, and in a non-resonant topology it can constrain the quartic coupling between the Higgs bosons and vector bosons. No significant excess relative to the Standard Model expectation is observed, and limits on the production cross-section are set at the 95 % confidence level for a heavy scalar resonance in the context of an extended Higgs sector, and for non-resonant Higgs boson pair production. Interpretation in terms of the coupling between a Higgs boson pair and two vector bosons is also provided: coupling values normalised to the Standard Model expectation of $\kappa_{2V} < -0.43$ and $\kappa_{2V} > 2.56$ are excluded at the 95 % confidence level in data.
Acceptance x efficiency versus $\kappa_{2V}$ for non-resonant signal of $HH$.
Acceptance x efficiency versus resonance mass for both narrow and broad resonance $X$ to $HH$.
Post-fit mass distribution of the $HH$ candidates in the signal region. The expected background is shown after the profile-likelihood fit to data with the background-only hypothesis; the narrow-width resonant signal at 800 GeV and the non-resonant signal at $\kappa_{2V}$ = 3 are overlaid, both normalised to the corresponding observed upper limits on the cross-section.
A search is presented for pair-production of long-lived neutral particles using 33 fb$^{-1}$ of $\sqrt{s} = 13$ TeV proton-proton collision data, collected during 2016 by the ATLAS detector at the LHC. This search focuses on a topology in which one long-lived particle decays in the ATLAS inner detector and the other decays in the muon spectrometer. Special techniques are employed to reconstruct the displaced tracks and vertices in the inner detector and in the muon spectrometer. One event is observed that passes the full event selection, which is consistent with the estimated background. Limits are placed on scalar boson propagators with masses from 125 GeV to 1000 GeV decaying into pairs of long-lived hidden-sector scalars with masses from 8 GeV to 400 GeV. The limits placed on several low-mass scalars extend previous exclusion limits in the range of proper lifetimes $c \tau$ from 5 cm to 1 m.
IDVx selection efficiency as a function of the radial decay position for $m_H = 125$ GeV.
IDVx selection efficiency as a function of the radial decay position for $m_s = 50$ GeV.
Observed $CL_S$ limits on $BR$ for $m_H = 125$ GeV.
A search for the direct production of the supersymmetric partners of $\tau$-leptons (staus) in final states with two hadronically decaying $\tau$-leptons is presented. The analysis uses a dataset of $pp$ collisions corresponding to an integrated luminosity of $139$ fb$^{-1}$, recorded with the ATLAS detector at the Large Hadron Collider at a center-of-mass energy of 13 TeV. No significant deviation from the expected Standard Model background is observed. Limits are derived in scenarios of direct production of stau pairs with each stau decaying into the stable lightest neutralino and one $\tau$-lepton in simplified models where the two stau mass eigenstates are degenerate. Stau masses from 120 GeV to 390 GeV are excluded at 95% confidence level for a massless lightest neutralino.
The observed upper limits on the model cross-section in units of pb for simplified models with combined ${\tilde{\tau}}^{+}_{R,L} {\tilde{\tau}}^{-}_{R,L}$ production. Three points at ${M({\tilde{\chi}}^{0}_{1})}=200GeV$ were removed from the plot but kept in the table because they overlapped with the plot's legend and are far from the exclusion contour.
The observed upper limits on the model cross-section in units of pb for simplified models with ${\tilde{\tau}}_L {\tilde{\tau}}_L$ only production. Three points at $M({\tilde{\chi}}^{0}_{1})=200GeV$ were removed from the plot but kept in the table because they overlapped with the plot's legend and are far from the exclusion contour.
The observed 95\% CL exclusion contours for the combined fit of SR-lowMass and SR-highMass for simplified models with combined ${\tilde{\tau}}^{+}_{R,L} {\tilde{\tau}}^{-}_{R,L}$ production.
This paper reports on a search for an extended scalar sector of the standard model, where a new CP-even (odd) boson decays to a Z boson and a lighter CP-odd (even) boson, and the latter further decays to a b quark pair. The Z boson is reconstructed via its decays to electron or muon pairs. The analysed data were recorded in proton-proton collisions at a center-of-mass energy $\sqrt{s} = $ 13 TeV, collected by the CMS experiment at the LHC during 2016, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. Data and predictions from the standard model are in agreement within the uncertainties. Upper limits at 95% confidence level are set on the production cross section times branching fraction, with masses of the new bosons up to 1000 GeV. The results are interpreted in the context of the two-Higgs-doublet model.
The dijet mass distribution in data and simulated background events after requiring all the analysis selections, for μμ + ee events. The various signal hypotheses displayed have been scaled to a cross section of 1 pb for display purposes.
The llbb mass distribution in data and simulated background events after requiring all the analysis selections, for μμ + ee events. The various signal hypotheses displayed have been scaled to a cross section of 1 pb for display purposes.
The rho distributions for the same-flavour category events corresponding to a signal hypothesis with mH = 261 GeV and mA = 150 GeV. The signal is normalised to its theoretical cross section.
A search for the electroweak production of charginos and sleptons decaying into final states with two electrons or muons is presented. The analysis is based on 139 fb$^{-1}$ of proton-proton collisions recorded by the ATLAS detector at the Large Hadron Collider at $\sqrt{s}=13$ TeV. Three $R$-parity-conserving scenarios where the lightest neutralino is the lightest supersymmetric particle are considered: the production of chargino pairs with decays via either $W$ bosons or sleptons, and the direct production of slepton pairs. The analysis is optimised for the first of these scenarios, but the results are also interpreted in the others. No significant deviations from the Standard Model expectations are observed and limits at 95 % confidence level are set on the masses of relevant supersymmetric particles in each of the scenarios. For a massless lightest neutralino, masses up to 420 GeV are excluded for the production of the lightest-chargino pairs assuming $W$-boson-mediated decays and up to 1 TeV for slepton-mediated decays, whereas for slepton-pair production masses up to 700 GeV are excluded assuming three generations of mass-degenerate sleptons.
- - - - - - - - Overview of HEPData Record - - - - - - - - <br/><br/> <b>Background Fit results:</b> <ul> <li><a href="89413?version=4&table=Background fit 1">CRs</a> <li><a href="89413?version=4&table=Background fit 2">VRs</a> <li><a href="89413?version=4&table=Background fit 5">inclusive DF-0J SRs</a> <li><a href="89413?version=4&table=Background fit 6">inclusive DF-1J SRs</a> <li><a href="89413?version=4&table=Background fit 3">inclusive SF-0J SRs</a> <li><a href="89413?version=4&table=Background fit 4">inclusive SF-1J SRs</a> </ul> <b>Kinematic distributions in VRs:</b> <ul> <li><a href="89413?version=4&table=VR kinematics 1">$m_{T2}$ in VR-top-low</a> <li><a href="89413?version=4&table=VR kinematics 2">$m_{T2}$ in VR-top-high</a> <li><a href="89413?version=4&table=VR kinematics 3">$E_T^{miss}$ in VR-WW-0J</a> <li><a href="89413?version=4&table=VR kinematics 4">$E_T^{miss}$ in VR-WW-1J</a> <li><a href="89413?version=4&table=VR kinematics 5">$E_T^{miss}$ sig in VR-VZ</a> <li><a href="89413?version=4&table=VR kinematics 6">$E_T^{miss}$ sig in VR-top-WW</a> </ul> <b>Kinematic distributions in SRs:</b> <ul> <li><a href="89413?version=4&table=SR kinematics 1">$m_{T2}$ in SR-SF-0J</a> <li><a href="89413?version=4&table=SR kinematics 2">$m_{T2}$ in SR-SF-1J</a> <li><a href="89413?version=4&table=SR kinematics 3">$m_{T2}$ in SR-DF-0J</a> <li><a href="89413?version=4&table=SR kinematics 4">$m_{T2}$ in SR-DF-1J</a> </ul> <b>Systematic uncertaities:</b> <ul> <li><a href="89413?version=4&table=Systematic uncertainties">dominant systematic uncertainties in the inclusive SRs</a> </ul> <b>Exclusion contours:</b> <ul> <li><a href="89413?version=4&table=Exclusion contour (exp) 1">expected exclusion contour direct chargino-pair production via W decay grid</a> <li><a href="89413?version=4&table=Exclusion contour (obs) 1">observed exclusion contour direct chargino-pair production via W decay grid</a> <li><a href="89413?version=4&table=Exclusion contour (exp) 2">expected exclusion contour direct chargino-pair production via slepton decay grid</a> <li><a href="89413?version=4&table=Exclusion contour (obs) 2">observed exclusion contour direct chargino-pair production via slepton decay grid</a> <li><a href="89413?version=4&table=Exclusion contour (exp) 3">expected exclusion contour direct slepton-pair production grid</a> <li><a href="89413?version=4&table=Exclusion contour (obs) 3">observed exclusion contour direct slepton-pair production grid</a> </ul> <br/><br/><b>AUXILIARY MATERIAL</b><br/> <b>Background Fit in binned SRs:</b> <ul> <li><a href="89413?version=4&table=Background fit 7">binned DF-0J SRs</a> <li><a href="89413?version=4&table=Background fit 8">binned DF-1J SRs</a> <li><a href="89413?version=4&table=Background fit 9">binned SF-0J SRs</a> <li><a href="89413?version=4&table=Background fit 10">binned SF-1J SRs</a> </ul> <b>Exclusion contours:</b> <ul> <li><a href="89413?version=4&table=Exclusion contour (exp) 4">expected exclusion contour left-handed slepton-pair production</a> <li><a href="89413?version=4&table=Exclusion contour (obs) 4">observed exclusion contour left-handed slepton-pair production</a> <li><a href="89413?version=4&table=Exclusion contour (exp) 5">expected exclusion contour right-handed slepton-pair production</a> <li><a href="89413?version=4&table=Exclusion contour (obs) 5">observed exclusion contour right-handed slepton-pair production</a> <li><a href="89413?version=4&table=Exclusion contour (exp) 6">expected exclusion contour selectron-pair production</a> <li><a href="89413?version=4&table=Exclusion contour (obs) 6">observed exclusion contour selectron-pair production</a> <li><a href="89413?version=4&table=Exclusion contour (exp) 7">expected exclusion contour left-handed selectron-pair production</a> <li><a href="89413?version=4&table=Exclusion contour (obs) 7">observed exclusion contour left-handed selectron-pair production</a> <li><a href="89413?version=4&table=Exclusion contour (exp) 8">expected exclusion contour right-handed selectron-pair production</a> <li><a href="89413?version=4&table=Exclusion contour (obs) 8">observed exclusion contour right-handed selectron-pair production</a> <li><a href="89413?version=4&table=Exclusion contour (exp) 9">expected exclusion contour smuon-pair production</a> <li><a href="89413?version=4&table=Exclusion contour (obs) 9">observed exclusion contour smuon-pair production</a> <li><a href="89413?version=4&table=Exclusion contour (exp) 10">expected exclusion contour left-handed smuon-pair production</a> <li><a href="89413?version=4&table=Exclusion contour (obs) 10">observed exclusion contour left-handed smuon-pair production</a> <li><a href="89413?version=4&table=Exclusion contour (exp) 11">expected exclusion contour right-handed smuon-pair production</a> <li><a href="89413?version=4&table=Exclusion contour (obs) 11">observed exclusion contour right-handed smuon-pair production</a> </ul> <b>Cross section upper limits:</b> <ul> <li><a href="89413?version=4&table=xsec upper limits 1">upper limits on signal cross section for direct chargino-pair production via W decay</a> <li><a href="89413?version=4&table=xsec upper limits 2">upper limits on signal cross section for direct chargino-pair production via slepton decay</a> <li><a href="89413?version=4&table=xsec upper limits 3">upper limits on signal cross section for direct slepton-pair production</a> </ul> <b>Acceptances and Efficiencies for direct chargino-pair production via W decay grid </b> <ul> <li> <b>Acceptance</b> <br/> <a href="89413?version=4&table=Acceptance SR-DF-0J-[100,inf) for C1C1WW grid">SR-DF-0J-[100,inf) </a> <a href="89413?version=4&table=Acceptance SR-DF-0J-[160,inf) for C1C1WW grid">SR-DF-0J-[160,inf) </a> <a href="89413?version=4&table=Acceptance SR-DF-0J-[100,120) for C1C1WW grid">SR-DF-0J-[100,120) </a> <a href="89413?version=4&table=Acceptance SR-DF-0J-[120,160) for C1C1WW grid">SR-DF-0J-[120,160) </a> <a href="89413?version=4&table=Acceptance SR-DF-0J-[100,105) for C1C1WW grid">SR-DF-0J-[100,105) </a> <a href="89413?version=4&table=Acceptance SR-DF-0J-[105,110) for C1C1WW grid">SR-DF-0J-[105,110) </a> <a href="89413?version=4&table=Acceptance SR-DF-0J-[110,120) for C1C1WW grid">SR-DF-0J-[110,120) </a> <a href="89413?version=4&table=Acceptance SR-DF-0J-[120,140) for C1C1WW grid">SR-DF-0J-[120,140) </a> <a href="89413?version=4&table=Acceptance SR-DF-0J-[140,160) for C1C1WW grid">SR-DF-0J-[140,160) </a> <a href="89413?version=4&table=Acceptance SR-DF-0J-[160,180) for C1C1WW grid">SR-DF-0J-[160,180) </a> <a href="89413?version=4&table=Acceptance SR-DF-0J-[180,220) for C1C1WW grid">SR-DF-0J-[180,220) </a> <a href="89413?version=4&table=Acceptance SR-DF-0J-[220,260) for C1C1WW grid">SR-DF-0J-[220,260) </a> <a href="89413?version=4&table=Acceptance SR-DF-0J-[260,inf) for C1C1WW grid">SR-DF-0J-[260,inf) </a><br/> <a href="89413?version=4&table=Acceptance SR-DF-1J-[100,inf) for C1C1WW grid">SR-DF-1J-[100,inf) </a> <a href="89413?version=4&table=Acceptance SR-DF-1J-[160,inf) for C1C1WW grid">SR-DF-1J-[160,inf) </a> <a href="89413?version=4&table=Acceptance SR-DF-1J-[100,120) for C1C1WW grid">SR-DF-1J-[100,120) </a> <a href="89413?version=4&table=Acceptance SR-DF-1J-[120,160) for C1C1WW grid">SR-DF-1J-[120,160) </a> <a href="89413?version=4&table=Acceptance SR-DF-1J-[100,105) for C1C1WW grid">SR-DF-1J-[100,105) </a> <a href="89413?version=4&table=Acceptance SR-DF-1J-[105,110) for C1C1WW grid">SR-DF-1J-[105,110) </a> <a href="89413?version=4&table=Acceptance SR-DF-1J-[110,120) for C1C1WW grid">SR-DF-1J-[110,120) </a> <a href="89413?version=4&table=Acceptance SR-DF-1J-[120,140) for C1C1WW grid">SR-DF-1J-[120,140) </a> <a href="89413?version=4&table=Acceptance SR-DF-1J-[140,160) for C1C1WW grid">SR-DF-1J-[140,160) </a> <a href="89413?version=4&table=Acceptance SR-DF-1J-[160,180) for C1C1WW grid">SR-DF-1J-[160,180) </a> <a href="89413?version=4&table=Acceptance SR-DF-1J-[180,220) for C1C1WW grid">SR-DF-1J-[180,220) </a> <a href="89413?version=4&table=Acceptance SR-DF-1J-[220,260) for C1C1WW grid">SR-DF-1J-[220,260) </a> <a href="89413?version=4&table=Acceptance SR-DF-1J-[260,inf) for C1C1WW grid">SR-DF-1J-[260,inf) </a><br/> <a href="89413?version=4&table=Acceptance SR-SF-0J-[100,inf) for C1C1WW grid">SR-SF-0J-[100,inf) </a> <a href="89413?version=4&table=Acceptance SR-SF-0J-[160,inf) for C1C1WW grid">SR-SF-0J-[160,inf) </a> <a href="89413?version=4&table=Acceptance SR-SF-0J-[100,120) for C1C1WW grid">SR-SF-0J-[100,120) </a> <a href="89413?version=4&table=Acceptance SR-SF-0J-[120,160) for C1C1WW grid">SR-SF-0J-[120,160) </a> <a href="89413?version=4&table=Acceptance SR-SF-0J-[100,105) for C1C1WW grid">SR-SF-0J-[100,105) </a> <a href="89413?version=4&table=Acceptance SR-SF-0J-[105,110) for C1C1WW grid">SR-SF-0J-[105,110) </a> <a href="89413?version=4&table=Acceptance SR-SF-0J-[110,120) for C1C1WW grid">SR-SF-0J-[110,120) </a> <a href="89413?version=4&table=Acceptance SR-SF-0J-[120,140) for C1C1WW grid">SR-SF-0J-[120,140) </a> <a href="89413?version=4&table=Acceptance SR-SF-0J-[140,160) for C1C1WW grid">SR-SF-0J-[140,160) </a> <a href="89413?version=4&table=Acceptance SR-SF-0J-[160,180) for C1C1WW grid">SR-SF-0J-[160,180) </a> <a href="89413?version=4&table=Acceptance SR-SF-0J-[180,220) for C1C1WW grid">SR-SF-0J-[180,220) </a> <a href="89413?version=4&table=Acceptance SR-SF-0J-[220,260) for C1C1WW grid">SR-SF-0J-[220,260) </a> <a href="89413?version=4&table=Acceptance SR-SF-0J-[260,inf) for C1C1WW grid">SR-SF-0J-[260,inf) </a><br/> <a href="89413?version=4&table=Acceptance SR-SF-1J-[100,inf) for C1C1WW grid">SR-SF-1J-[100,inf) </a> <a href="89413?version=4&table=Acceptance SR-SF-1J-[160,inf) for C1C1WW grid">SR-SF-1J-[160,inf) </a> <a href="89413?version=4&table=Acceptance SR-SF-1J-[100,120) for C1C1WW grid">SR-SF-1J-[100,120) </a> <a href="89413?version=4&table=Acceptance SR-SF-1J-[120,160) for C1C1WW grid">SR-SF-1J-[120,160) </a> <a href="89413?version=4&table=Acceptance SR-SF-1J-[100,105) for C1C1WW grid">SR-SF-1J-[100,105) </a> <a href="89413?version=4&table=Acceptance SR-SF-1J-[105,110) for C1C1WW grid">SR-SF-1J-[105,110) </a> <a href="89413?version=4&table=Acceptance SR-SF-1J-[110,120) for C1C1WW grid">SR-SF-1J-[110,120) </a> <a href="89413?version=4&table=Acceptance SR-SF-1J-[120,140) for C1C1WW grid">SR-SF-1J-[120,140) </a> <a href="89413?version=4&table=Acceptance SR-SF-1J-[140,160) for C1C1WW grid">SR-SF-1J-[140,160) </a> <a href="89413?version=4&table=Acceptance SR-SF-1J-[160,180) for C1C1WW grid">SR-SF-1J-[160,180) </a> <a href="89413?version=4&table=Acceptance SR-SF-1J-[180,220) for C1C1WW grid">SR-SF-1J-[180,220) </a> <a href="89413?version=4&table=Acceptance SR-SF-1J-[220,260) for C1C1WW grid">SR-SF-1J-[220,260) </a> <a href="89413?version=4&table=Acceptance SR-SF-1J-[260,inf) for C1C1WW grid">SR-SF-1J-[260,inf) </a><br/> <li> <b>Efficiency</b> <br/> <a href="89413?version=4&table=Efficiency SR-DF-0J-[100,inf) for C1C1WW grid">SR-DF-0J-[100,inf) </a> <a href="89413?version=4&table=Efficiency SR-DF-0J-[160,inf) for C1C1WW grid">SR-DF-0J-[160,inf) </a> <a href="89413?version=4&table=Efficiency SR-DF-0J-[100,120) for C1C1WW grid">SR-DF-0J-[100,120) </a> <a href="89413?version=4&table=Efficiency SR-DF-0J-[120,160) for C1C1WW grid">SR-DF-0J-[120,160) </a> <a href="89413?version=4&table=Efficiency SR-DF-0J-[100,105) for C1C1WW grid">SR-DF-0J-[100,105) </a> <a href="89413?version=4&table=Efficiency SR-DF-0J-[105,110) for C1C1WW grid">SR-DF-0J-[105,110) </a> <a href="89413?version=4&table=Efficiency SR-DF-0J-[110,120) for C1C1WW grid">SR-DF-0J-[110,120) </a> <a href="89413?version=4&table=Efficiency SR-DF-0J-[120,140) for C1C1WW grid">SR-DF-0J-[120,140) </a> <a href="89413?version=4&table=Efficiency SR-DF-0J-[140,160) for C1C1WW grid">SR-DF-0J-[140,160) </a> <a href="89413?version=4&table=Efficiency SR-DF-0J-[160,180) for C1C1WW grid">SR-DF-0J-[160,180) </a> <a href="89413?version=4&table=Efficiency SR-DF-0J-[180,220) for C1C1WW grid">SR-DF-0J-[180,220) </a> <a href="89413?version=4&table=Efficiency SR-DF-0J-[220,260) for C1C1WW grid">SR-DF-0J-[220,260) </a> <a href="89413?version=4&table=Efficiency SR-DF-0J-[260,inf) for C1C1WW grid">SR-DF-0J-[260,inf) </a><br/> <a href="89413?version=4&table=Efficiency SR-DF-1J-[100,inf) for C1C1WW grid">SR-DF-1J-[100,inf) </a> <a href="89413?version=4&table=Efficiency SR-DF-1J-[160,inf) for C1C1WW grid">SR-DF-1J-[160,inf) </a> <a href="89413?version=4&table=Efficiency SR-DF-1J-[100,120) for C1C1WW grid">SR-DF-1J-[100,120) </a> <a href="89413?version=4&table=Efficiency SR-DF-1J-[120,160) for C1C1WW grid">SR-DF-1J-[120,160) </a> <a href="89413?version=4&table=Efficiency SR-DF-1J-[100,105) for C1C1WW grid">SR-DF-1J-[100,105) </a> <a href="89413?version=4&table=Efficiency SR-DF-1J-[105,110) for C1C1WW grid">SR-DF-1J-[105,110) </a> <a href="89413?version=4&table=Efficiency SR-DF-1J-[110,120) for C1C1WW grid">SR-DF-1J-[110,120) </a> <a href="89413?version=4&table=Efficiency SR-DF-1J-[120,140) for C1C1WW grid">SR-DF-1J-[120,140) </a> <a href="89413?version=4&table=Efficiency SR-DF-1J-[140,160) for C1C1WW grid">SR-DF-1J-[140,160) </a> <a href="89413?version=4&table=Efficiency SR-DF-1J-[160,180) for C1C1WW grid">SR-DF-1J-[160,180) </a> <a href="89413?version=4&table=Efficiency SR-DF-1J-[180,220) for C1C1WW grid">SR-DF-1J-[180,220) </a> <a href="89413?version=4&table=Efficiency SR-DF-1J-[220,260) for C1C1WW grid">SR-DF-1J-[220,260) </a> <a href="89413?version=4&table=Efficiency SR-DF-1J-[260,inf) for C1C1WW grid">SR-DF-1J-[260,inf) </a><br/> <a href="89413?version=4&table=Efficiency SR-SF-0J-[100,inf) for C1C1WW grid">SR-SF-0J-[100,inf) </a> <a href="89413?version=4&table=Efficiency SR-SF-0J-[160,inf) for C1C1WW grid">SR-SF-0J-[160,inf) </a> <a href="89413?version=4&table=Efficiency SR-SF-0J-[100,120) for C1C1WW grid">SR-SF-0J-[100,120) </a> <a href="89413?version=4&table=Efficiency SR-SF-0J-[120,160) for C1C1WW grid">SR-SF-0J-[120,160) </a> <a href="89413?version=4&table=Efficiency SR-SF-0J-[100,105) for C1C1WW grid">SR-SF-0J-[100,105) </a> <a href="89413?version=4&table=Efficiency SR-SF-0J-[105,110) for C1C1WW grid">SR-SF-0J-[105,110) </a> <a href="89413?version=4&table=Efficiency SR-SF-0J-[110,120) for C1C1WW grid">SR-SF-0J-[110,120) </a> <a href="89413?version=4&table=Efficiency SR-SF-0J-[120,140) for C1C1WW grid">SR-SF-0J-[120,140) </a> <a href="89413?version=4&table=Efficiency SR-SF-0J-[140,160) for C1C1WW grid">SR-SF-0J-[140,160) </a> <a href="89413?version=4&table=Efficiency SR-SF-0J-[160,180) for C1C1WW grid">SR-SF-0J-[160,180) </a> <a href="89413?version=4&table=Efficiency SR-SF-0J-[180,220) for C1C1WW grid">SR-SF-0J-[180,220) </a> <a href="89413?version=4&table=Efficiency SR-SF-0J-[220,260) for C1C1WW grid">SR-SF-0J-[220,260) </a> <a href="89413?version=4&table=Efficiency SR-SF-0J-[260,inf) for C1C1WW grid">SR-SF-0J-[260,inf) </a><br/> <a href="89413?version=4&table=Efficiency SR-SF-1J-[100,inf) for C1C1WW grid">SR-SF-1J-[100,inf) </a> <a href="89413?version=4&table=Efficiency SR-SF-1J-[160,inf) for C1C1WW grid">SR-SF-1J-[160,inf) </a> <a href="89413?version=4&table=Efficiency SR-SF-1J-[100,120) for C1C1WW grid">SR-SF-1J-[100,120) </a> <a href="89413?version=4&table=Efficiency SR-SF-1J-[120,160) for C1C1WW grid">SR-SF-1J-[120,160) </a> <a href="89413?version=4&table=Efficiency SR-SF-1J-[100,105) for C1C1WW grid">SR-SF-1J-[100,105) </a> <a href="89413?version=4&table=Efficiency SR-SF-1J-[105,110) for C1C1WW grid">SR-SF-1J-[105,110) </a> <a href="89413?version=4&table=Efficiency SR-SF-1J-[110,120) for C1C1WW grid">SR-SF-1J-[110,120) </a> <a href="89413?version=4&table=Efficiency SR-SF-1J-[120,140) for C1C1WW grid">SR-SF-1J-[120,140) </a> <a href="89413?version=4&table=Efficiency SR-SF-1J-[140,160) for C1C1WW grid">SR-SF-1J-[140,160) </a> <a href="89413?version=4&table=Efficiency SR-SF-1J-[160,180) for C1C1WW grid">SR-SF-1J-[160,180) </a> <a href="89413?version=4&table=Efficiency SR-SF-1J-[180,220) for C1C1WW grid">SR-SF-1J-[180,220) </a> <a href="89413?version=4&table=Efficiency SR-SF-1J-[220,260) for C1C1WW grid">SR-SF-1J-[220,260) </a> <a href="89413?version=4&table=Efficiency SR-SF-1J-[260,inf) for C1C1WW grid">SR-SF-1J-[260,inf) </a><br/> </ul> <b>Cutflow:</b> <ul> <li><a href="89413?version=4&table=Cutflow 1">Cutflow for direct chargino-pair production via W decay $m(\tilde{\chi}^{\pm}_1,\tilde{\chi}^{0}_1)=(300,50) GeV$</a> <li><a href="89413?version=4&table=Cutflow 2">Cutflow for direct chargino-pair production via slepton decay $m(\tilde{\chi}^{\pm}_1,\tilde{l},\tilde{\chi}^{0}_1)=(600,300,1) GeV$</a> <li><a href="89413?version=4&table=Cutflow 3">Cutflow for direct slepton-pair production $m(\tilde{l},\tilde{\chi}^{0}_1)=(400,200) GeV$</a> </ul> <b>SimpleAnalysis framework implementation</b> of the search SRs is available under "Resources" (purple button on the left)
Observed events and predicted background yields from the fit for the CRs. For backgrounds whose normalisation is extracted from the fit, the yield expected from the simulation before the fit is also reported. The background denoted as "Other" in the Table includes the non-dominant background sources for this analysis, i.e. Z+jets, $t\bar t$ +V, Higgs and Drell-Yan events. A "–" symbol indicates that the background contribution is negligible.
Observed events and predicted post-fit background yields in the VRs. For backgrounds whose normalisation is extracted from the fit in the CRs, the yield expected from the simulation before the fit is also reported. The background denoted as "Other" includes the non-dominant background sources for this analysis, i.e. Z+jets, $t\bar t$ +V, Higgs and Drell-Yan events. A "–" symbol indicates that the background contribution is negligible.
A search for non-resonant Higgs boson pair production, as predicted by the Standard Model, is presented, where one of the Higgs bosons decays via the $H\rightarrow bb$ channel and the other via one of the $H \rightarrow WW^*/ZZ^*/\tau\tau$ channels. The analysis selection requires events to have at least two $b$-tagged jets and exactly two leptons (electrons or muons) with opposite electric charge in the final state. Candidate events consistent with Higgs boson pair production are selected using a multi-class neural network discriminant. The analysis uses 139 fb$^{-1}$ of $pp$ collision data recorded at a centre-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. An observed (expected) upper limit of 1.2 ($0.9^{+0.4}_{-0.3}$) pb is set on the non-resonant Higgs boson pair production cross-section at 95% confidence level, which is equivalent to 40 ($29^{+14}_{-9}$) times the value predicted in the Standard Model.
Reconstruction-level analysis selection efficiency for the $HH \rightarrow bbWW^* \rightarrow bbl\nu l\nu$ signal process as a function of the truth-level $HH$ invariant mass, $m_{HH}$. Each color indicates an additional selection applied sequentially and in the order indicated in the legend with respect to the starting sample of events satisfying the analysis preselection requirements and having at least two $b$-tagged jets. In the legend, ``Trigger'' refers to enforcing the analysis' trigger requirements. For reference, overlaid in grey colour and with arbitrary normalisation is the truth level $m_{HH}$ distribution for events having only the preselection criteria applied. The total efficiency for the tightest selection that is shown (red line), which has selection requirements similar to those of the analysis' signal regions SR-SF and SR-DF, is $7.1\%$.
Expected and observed $95\%$ CL limits on the cross-section of ggF non-resonant Higgs boson pair production as a function of the Higgs boson self-coupling modifier, $\kappa_{\lambda} = \lambda_{HHH} / \lambda_{HHH}^{\textit{SM}}$. The $\pm 1 \sigma$ and $\pm 2 \sigma$ variations about the expected limit, due to statistical and systematic uncertainties, are also shown. The method used for producing estimates of $HH$ production at non-SM values of $\kappa_{\lambda}$ is fully described in arXiv:1906.02025. The theory prediction curve represents the scenario where all parameters and couplings are set to their SM values except for $\kappa_{\lambda}$, also described in arXiv:1906.02025. The uncertainty band on the theory prediction indicates the theoretical uncertainty of this prediction. No additional analysis optimisation relative to that appearing in the main body of the analysis is performed to become particularly sensitive to non-SM values of $\kappa_{\lambda}$. The vertical dashed line indicates the SM scenario with $\kappa_{\lambda} = 1$.
A search for long-lived particles decaying into an oppositely charged lepton pair, $\mu\mu$, $ee$, or $e\mu$, is presented using 32.8 fb$^{-1}$ of $pp$ collision data collected at $\sqrt{s}=13$ TeV by the ATLAS detector at the LHC. Candidate leptons are required to form a vertex, within the inner tracking volume of ATLAS, displaced from the primary $pp$ interaction region. No lepton pairs with an invariant mass greater than 12 GeV are observed, consistent with the background expectations derived from data. The detection efficiencies for generic resonances with lifetimes ($c\tau$) of 100-1000 mm decaying into a dilepton pair with masses between 0.1-1.0 TeV are presented as a function of $p_T$ and decay radius of the resonances to allow the extraction of upper limits on the cross sections for theoretical models. The result is also interpreted in a supersymmetric model in which the lightest neutralino, produced via squark-antisquark production, decays into $\ell^{+}\ell^{'-}\nu$ ($\ell, \ell^{'} = e$, $\mu$) with a finite lifetime due to the presence of R-parity violating couplings. Cross-section limits are presented for specific squark and neutralino masses. For a 700 GeV squark, neutralinos with masses of 50-500 GeV and mean proper lifetimes corresponding to $c\tau$ values between 1 mm to 6 m are excluded. For a 1.6 TeV squark, $c\tau$ values between 3 mm to 1 m are excluded for 1.3 TeV neutralinos.
<h1>Overview of reinterpretation material</h1><p><b>Important note:</b> A detailed explanation of the reinterpretation material can be found <a href="https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/SUSY-2017-04/hepdata_info.pdf">here</a>.<br/>Please read this stand-alone document before reinterpreting the search.</p><h2>Parameterized detection efficiencies</h2><p>RPV SUSY model: Tables <a href="90606?version=1&table=Table27">27</a> to <a href="90606?version=1&table=Table44">44</a><br/>Z' toy model: Tables <a href="90606?version=1&table=Table45">45</a> to <a href="90606?version=1&table=Table59">59</a></p><h2>Further material for the RPV SUSY model</h2><p>Acceptances: Tables <a href="90606?version=1&table=Table18">18</a> (ee), <a href="90606?version=1&table=Table19">19</a> (emu) and <a href="90606?version=1&table=Table20">20</a> (mumu)<br/>Detection efficiencies: Tables <a href="90606?version=1&table=Table21">21</a> (ee), <a href="90606?version=1&table=Table22">22</a> (emu) and <a href="90606?version=1&table=Table23">23</a> (mumu)<br/>Overall signal efficiencies: Tables <a href="90606?version=1&table=Table24">24</a> (ee), <a href="90606?version=1&table=Table25">25</a> (emu) and <a href="90606?version=1&table=Table26">26</a> (mumu)</p><h2>Further material for the Z' toy model</h2><p>Acceptances, detection efficiencies and overall signal efficiencies: Tables <a href="90606?version=1&table=Table60">60</a> (mZ' = 100 GeV) to <a href="90606?version=1&table=Table64">64</a> (mZ' = 1000 GeV)</p>
dRcos distribution of dimuon pairs (scaled) and dimuon vertices in the cosmic rays control region. The distribution of all dimuon pairs is scaled to the DV distribution.
Dependence of the overall signal efficiency on the transverse decay radius Rxy of the long-lived Z' for Z' -> ee. The error bars indicate the total uncertainties.
Narrow resonances decaying into $WW$, $WZ$ or $ZZ$ boson pairs are searched for in 139 fb$^{-1}$ of proton-proton collision data at a centre-of-mass energy of $\sqrt{s}=13$ TeV recorded with the ATLAS detector at the Large Hadron Collider from 2015 to 2018. The diboson system is reconstructed using pairs of high transverse momentum, large-radius jets. These jets are built from a combination of calorimeter- and tracker-inputs compatible with the hadronic decay of a boosted $W$ or $Z$ boson, using jet mass and substructure properties. The search is performed for diboson resonances with masses greater than 1.3 TeV. No significant deviations from the background expectations are observed. Exclusion limits at the 95% confidence level are set on the production cross-section times branching ratio into dibosons for resonances in a range of theories beyond the Standard Model, with the highest excluded mass of a new gauge boson at 3.8 TeV in the context of mass-degenerate resonances that couple predominantly to gauge bosons.
Limit Plot
Limit Plot
Limit Plot
A search for magnetic monopoles and high-electric-charge objects is presented using 34.4 fb$^{-1}$ of 13 TeV $pp$ collision data collected by the ATLAS detector at the LHC during 2015 and 2016. The considered signature is based upon high ionization in the transition radiation tracker of the inner detector associated with a pencil-shape energy deposit in the electromagnetic calorimeter. The data were collected by a dedicated trigger based on the tracker high-threshold hit capability. The results are interpreted in models of Drell-Yan pair production of stable particles with two spin hypotheses (0 and 1/2) and masses ranging from 200 GeV to 4000 GeV. The search improves by approximately a factor of five the constraints on the direct production of magnetic monopoles carrying one or two Dirac magnetic charges and stable objects with electric charge in the range $20\le|z|\le60$ and extends the charge range to $60<|z|\le100$.
Observed 95% confidence-level upper limits on the cross section for Drell-Yan spin-0 monopole production as a function of mass for magnetic charges $|g|=1g_D$ and $|g|=2g_D$.
Observed 95% confidence-level upper limits on the cross section for Drell-Yan spin-0 HECO production as a function of mass for various values of electric charge in the range $20\le|z|\le100$.
Observed 95% confidence-level upper limits on the cross section for Drell-Yan spin-1/2 monopole production as a function of mass for magnetic charges $|g|=1g_D$ and $|g|=2g_D$.
The problems of neutrino masses, matter-antimatter asymmetry, and dark matter could be successfully addressed by postulating right-handed neutrinos with Majorana masses below the electroweak scale. In this work, leptonic decays of $W$ bosons extracted from 32.9 fb$^{-1}$ to 36.1 fb$^{-1}$ of 13 TeV proton-proton collisions at the LHC are used to search for heavy neutral leptons (HNLs) that are produced through mixing with muon or electron neutrinos. The search is conducted using the ATLAS detector in both prompt and displaced leptonic decay signatures. The prompt signature requires three leptons produced at the interaction point (either $\mu\mu e$ or $e e\mu$) with a veto on same-flavour opposite-charge topologies. The displaced signature comprises a prompt muon from the $W$ boson decay and the requirement of a dilepton vertex (either $\mu\mu$ or $\mu e$) displaced in the transverse plane by 4-300 mm from the interaction point. The search sets constraints on the HNL mixing to muon and electron neutrinos for HNL masses in the range 4.5-50 GeV.
Displaced HNL event selection efficiency as a function of mean proper decay length for HNL mass 5, 7.5, 10 and 12.5 GeV.
Prompt HNL event selection efficiency as a function of mean proper decay length for HNL mass 10 GeV.
Displaced HNL search observed 95% confidence level exclusion contour in $|U_{\mu}|^2$ as a function of HNL mass (LNC case).