Searches for electroweak production of supersymmetric particles with compressed mass spectra in $\sqrt{s}=13$ TeV $pp$ collisions with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
No Journal Information, 2019.
Inspire Record 1767649 DOI 10.17182/hepdata.91374

This paper presents results of searches for electroweak production of supersymmetric particles in models with compressed mass spectra. The searches use 139 fb$^{-1}$ of $\sqrt{s}=13$ TeV proton-proton collision data collected by the ATLAS experiment at the Large Hadron Collider. Events with missing transverse momentum and two same-flavor, oppositely charged, low transverse momentum leptons are selected, and are further categorized by the presence of hadronic activity from initial-state radiation or a topology compatible with vector-boson fusion processes. The data are found to be consistent with predictions from the Standard Model. The results are interpreted using simplified models of $R$-parity-conserving supersymmetry in which the lightest supersymmetric partner is a neutralino with a mass similar to the lightest chargino, the second-to-lightest neutralino or the slepton. Lower limits on the masses of charginos in different simplified models range from 193 GeV to 240 GeV for moderate mass splittings, and extend down to mass splittings of 1.5 GeV to 2.4 GeV at the LEP chargino bounds (92.4 GeV). Similar lower limits on degenerate light-flavor sleptons extend up to masses of 251 GeV and down to mass splittings of 550 MeV. Constraints on vector-boson fusion production of electroweak SUSY states are also presented.

98 data tables

Number of signal events in SR-E-1L1T for the (m($\tilde{\chi}_{2}^{0}$),m($\tilde{\chi}_{1}^{0}$)) = (155 GeV, 150 GeV) Higgsino signal model at different stages of selection before and after weighting events to correspond to 140/fb.

Number of signal events in SR-E-high for the (m($\tilde{\chi}_{2}^{0}$),m($\tilde{\chi}_{1}^{0}$)) = (155 GeV, 150 GeV) Higgsino signal model at different stages of selection before and after weighting events to correspond to 140/fb.

Number of signal events in SR-E-low for the (m($\tilde{\chi}_{2}^{0}$),m($\tilde{\chi}_{1}^{0}$)) = (155 GeV, 150 GeV) Higgsino signal model at different stages of selection before and after weighting events to correspond to 140/fb.

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Measurement of the $Z(\rightarrow\ell^+\ell^-)\gamma$ production cross-section in $pp$ collisions at $\sqrt{s} =13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
No Journal Information, 2019.
Inspire Record 1764342 DOI 10.17182/hepdata.89875

The production of a prompt photon in association with a $Z$ boson is studied in proton-proton collisions at a centre-of-mass energy $\sqrt{s} =$ 13 TeV. The analysis uses a data sample with an integrated luminosity of 139 fb$^{-1}$ collected by the ATLAS detector at the LHC from 2015 to 2018. The production cross-section for the process $pp \rightarrow \ell^+\ell^-\gamma+X$ ($\ell = e, \mu$) is measured within a fiducial phase-space region defined by kinematic requirements on the photon and the leptons, and by isolation requirements on the photon. An experimental precision of 2.9% is achieved for the fiducial cross-section. Differential cross-sections are measured as a function of each of six kinematic variables characterising the $\ell^+\ell^-\gamma$ system. The data are compared with theoretical predictions based on next-to-leading-order and next-to-next-to-leading-order perturbative QCD calculations. The impact of next-to-leading-order electroweak corrections is also considered.

7 data tables

The measured fiducial cross section. "Uncor" uncertainty includes all systematic uncertainties that are uncorrelated between electron and muon channels such as the uncertainty on the electron identification efficiency and the uncorrelated component of the background uncertainties. The parton-to-particle correction factor $C_{theory}$ is the ratio of the cross-section predicted by Sherpa LO samples at particle level within the fiducial phase-space region defined in Table 4 to the predicted cross-section at parton level within the same fiducial region but with the smooth-cone isolation prescription defined above replacing the particle-level photon isolation criterion, and with Born-level leptons in place of dressed leptons. This correction should be applied on fixed order parton-level calculations. The systematic uncertainty is evaluated from a comparison with the correction factor obtained using events generated with SHERPA 2.2.2 at NLO. In the case that the calculations are valid for dressed leptons, a modified correction factor excluding the Born-to-dressed lepton correction should be applied instead. This correction only takes into account the particle-level isolation criteria, and is provided separately here. The Sherpa 2.2.8 NLO cross-sections given below include a small contribution from EW $Z\gamma jj$ production of 4.57 fb.

The measured fiducial cross section vs $E_{\mathrm{T}}^\gamma$. The central values are provided along with the statistical and systematic uncertainties together with the sign information. The statistical and "Uncor" uncertainty should be treated as uncorrelated bin-to-bin, while the rest are correlated between bins, and they are written as signed NP variations. The parton-to-particle correction factor $C_{theory}$ is the ratio of the cross-section predicted by Sherpa LO samples at particle level within the fiducial phase-space region defined in Table 4 to the predicted cross-section at parton level within the same fiducial region but with the smooth-cone isolation prescription defined above replacing the particle-level photon isolation criterion, and with Born-level leptons in place of dressed leptons. This correction should be applied on fixed order parton-level calculations. The systematic uncertainty is evaluated from a comparison with the correction factor obtained using events generated with SHERPA 2.2.2 at NLO. In the case that the calculations are valid for dressed leptons, a modified correction factor excluding the Born-to-dressed lepton correction should be applied instead. This correction only takes into account the particle-level isolation criteria, and is provided separately here. The Sherpa 2.2.8 NLO cross-sections given below include a small contribution from EW $Z\gamma jj$ production.

The measured fiducial cross section vs $|\eta^\gamma|$. The central values are provided along with the statistical and systematic uncertainties together with the sign information. The statistical and "Uncor" uncertainty should be treated as uncorrelated bin-to-bin, while the rest are correlated between bins, and they are written as signed NP variations. The parton-to-particle correction factor $C_{theory}$ is the ratio of the cross-section predicted by Sherpa LO samples at particle level within the fiducial phase-space region defined in Table 4 to the predicted cross-section at parton level within the same fiducial region but with the smooth-cone isolation prescription defined above replacing the particle-level photon isolation criterion, and with Born-level leptons in place of dressed leptons. This correction should be applied on fixed order parton-level calculations. The systematic uncertainty is evaluated from a comparison with the correction factor obtained using events generated with SHERPA 2.2.2 at NLO. In the case that the calculations are valid for dressed leptons, a modified correction factor excluding the Born-to-dressed lepton correction should be applied instead. This correction only takes into account the particle-level isolation criteria, and is provided separately here. The Sherpa 2.2.8 NLO cross-sections given below include a small contribution from EW $Z\gamma jj$ production.

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Search for direct production of electroweakinos in final states with one lepton, missing transverse momentum and a Higgs boson decaying into two $b$-jets in (pp) collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
No Journal Information, 2019.
Inspire Record 1755298 DOI 10.17182/hepdata.90607

The results of a search for electroweakino pair production $pp \rightarrow \tilde\chi^\pm_1 \tilde\chi^0_2$ in which the chargino ($\tilde\chi^\pm_1$) decays into a $W$ boson and the lightest neutralino ($\tilde\chi^0_1$), while the heavier neutralino ($\tilde\chi^0_2$) decays into the Standard Model 125 GeV Higgs boson and a second $\tilde\chi^0_1$ are presented. The signal selection requires a pair of $b$-tagged jets consistent with those from a Higgs boson decay, and either an electron or a muon from the $W$ boson decay, together with missing transverse momentum from the corresponding neutrino and the stable neutralinos. The analysis is based on data corresponding to 139 $\mathrm{fb}^{-1}$ of $\sqrt{s}=13$ TeV $pp$ collisions provided by the Large Hadron Collider and recorded by the ATLAS detector. No statistically significant evidence of an excess of events above the Standard Model expectation is found. Limits are set on the direct production of the electroweakinos in simplified models, assuming pure wino cross-sections. Masses of $\tilde{\chi}^{\pm}_{1}/\tilde{\chi}^{0}_{2}$ up to 740 GeV are excluded at 95% confidence level for a massless $\tilde{\chi}^{0}_{1}$.

53 data tables

Signal acceptance in SR-HM for simplified models with $\tilde\chi^\pm_1 \tilde\chi^0_2 \rightarrow Wh\tilde\chi^0_1\tilde\chi^0_1, W \rightarrow l\nu, h \rightarrow b\bar{b}$ production. 1lb\bar{b}$ production

Signal acceptance in SR-HM high $m_{CT}$ for simplified models with $\tilde\chi^\pm_1 \tilde\chi^0_2 \rightarrow Wh\tilde\chi^0_1\tilde\chi^0_1, W \rightarrow l\nu, h \rightarrow b\bar{b}$ production.

Signal acceptance in SR-HM low $m_{CT}$ for simplified models with $\tilde\chi^\pm_1 \tilde\chi^0_2 \rightarrow Wh\tilde\chi^0_1\tilde\chi^0_1, W \rightarrow l\nu, h \rightarrow b\bar{b}$ production.

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Search for squarks and gluinos in final states with same-sign leptons and jets using 139 fb$^{-1}$ of data collected with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
No Journal Information, 2019.
Inspire Record 1754675 DOI 10.17182/hepdata.91214

A search for supersymmetric partners of gluons and quarks is presented, involving signatures with jets and either two isolated leptons (electrons or muons) with the same electric charge, or at least three isolated leptons. A data sample of proton-proton collisions at $\sqrt{s}$ = 13 TeV recorded with the ATLAS detector at the Large Hadron Collider between 2015 and 2018, corresponding to a total integrated luminosity of 139 fb$^{-1}$, is used for the search. No significant excess over the Standard Model expectation is observed. The results are interpreted in simplified supersymmetric models featuring both R-parity conservation and R-parity violation, raising the exclusion limits beyond those of previous ATLAS searches to 1600 GeV for gluino masses and 750 GeV for bottom and top squark masses in these scenarios.

30 data tables

Best observed 95% CL exclusion contours selected from Rpc2L1b and Rpc2L2b on the lightest bottom squark and lightest neutralino masses in a SUSY scenario where pairs of bottom-antibottom squarks are produced and decay into the lightest neutralino via a chargino, $\tilde b^{}_{1}\to t\tilde{\chi}_1^-$ followed by $\tilde{\chi}_1^\pm\to W^\pm\tilde{\chi}_1^0$.

Number of signal events expected for 139 fb$^{-1}$ at different stages of the event selection for the signal region Rpc2L0b, in a SUSY scenario where gluinos are produced in pairs and decay into the lightest neutralino via a two-steps cascade, $\tilde g\to q\bar{q}^{'}\tilde{\chi}_1^\pm$ followed by $\tilde{\chi}_1^\pm\to W^\pm\tilde{\chi}_2^0$ and $\tilde{\chi}_2^0\to Z\tilde{\chi}_1^0$. The masses of the superpartners involved in the process are set to $m(\tilde g)$ = 1600 GeV, $m(\tilde \chi_1^\pm)$ = 1200 GeV, $m(\tilde \chi_2^0)$ = 1000 GeV and $m(\tilde \chi_1^0)$ = 800 GeV. Only statistical uncertainties are shown.

Number of signal events expected for 139 fb$^{-1}$ at different stages of the event selection for the signal region Rpc2L1b, in a SUSY scenario where pairs of bottom-antibottom squarks are produced and decay into the lightest neutralino via a chargino, $\tilde b^{}_{1}\to t\tilde{\chi}_1^-$ followed by $\tilde{\chi}_1^\pm\to W^\pm\tilde{\chi}_1^0$. The masses of the superpartners involved in the process are set to $m(\tilde{b}^{}_1)$ = 850 GeV, $m(\tilde \chi_1^\pm)$ = 500 GeV and $m(\tilde \chi_1^0)$ = 400 GeV. Only statistical uncertainties are shown.

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Search for electroweak production of charginos and sleptons decaying into final states with two leptons and missing transverse momentum in $\sqrt{s}=13$ TeV $pp$ collisions using the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
No Journal Information, 2019.
Inspire Record 1750597 DOI 10.17182/hepdata.89413

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.

154 data tables

- - - - - - - - Overview of HEPData Record - - - - - - - - <br/><br/> <b>Background Fit results:</b> <ul> <li><a href="89413?version=1&table=Backgroundfit1">CRs</a> <li><a href="89413?version=1&table=Backgroundfit2">VRs</a> <li><a href="89413?version=1&table=Backgroundfit5">inclusive DF-0J SRs</a> <li><a href="89413?version=1&table=Backgroundfit6">inclusive DF-1J SRs</a> <li><a href="89413?version=1&table=Backgroundfit3">inclusive SF-0J SRs</a> <li><a href="89413?version=1&table=Backgroundfit4">inclusive SF-1J SRs</a> </ul> <b>Kinematic distributions in VRs:</b> <ul> <li><a href="89413?version=1&table=VRkinematics1">$m_{T2}$ in VR-top-low</a> <li><a href="89413?version=1&table=VRkinematics2">$m_{T2}$ in VR-top-high</a> <li><a href="89413?version=1&table=VRkinematics3">$E_T^{miss}$ in VR-WW-0J</a> <li><a href="89413?version=1&table=VRkinematics4">$E_T^{miss}$ in VR-WW-1J</a> <li><a href="89413?version=1&table=VRkinematics5">$E_T^{miss}$ sig in VR-VZ</a> <li><a href="89413?version=1&table=VRkinematics6">$E_T^{miss}$ sig in VR-top-WW</a> </ul> <b>Kinematic distributions in SRs:</b> <ul> <li><a href="89413?version=1&table=SRkinematics1">$m_{T2}$ in SR-SF-0J</a> <li><a href="89413?version=1&table=SRkinematics2">$m_{T2}$ in SR-SF-1J</a> <li><a href="89413?version=1&table=SRkinematics3">$m_{T2}$ in SR-DF-0J</a> <li><a href="89413?version=1&table=SRkinematics4">$m_{T2}$ in SR-DF-1J</a> </ul> <b>Systematic uncertaities:</b> <ul> <li><a href="89413?version=1&table=Systematic uncertainties">dominant systematic uncertainties in the inclusive SRs</a> </ul> <b>Exclusion contours:</b> <ul> <li><a href="89413?version=1&table=Exclusioncontour(obs)1">expected exclusion contour direct chargino-pair production via W decay grid</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)1">observed exclusion contour direct chargino-pair production via W decay grid</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)2">expected exclusion contour direct chargino-pair production via slepton decay grid</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)2">observed exclusion contour direct chargino-pair production via slepton decay grid</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)3">expected exclusion contour direct slepton-pair production grid</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)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=1&table=Backgroundfit7">binned DF-0J SRs</a> <li><a href="89413?version=1&table=Backgroundfit8">binned DF-1J SRs</a> <li><a href="89413?version=1&table=Backgroundfit9">binned SF-0J SRs</a> <li><a href="89413?version=1&table=Backgroundfit10">binned SF-1J SRs</a> </ul> <b>Exclusion contours:</b> <ul> <li><a href="89413?version=1&table=Exclusioncontour(obs)4">expected exclusion contour left-handed slepton-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)4">observed exclusion contour left-handed slepton-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)5">expected exclusion contour right-handed slepton-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)5">observed exclusion contour right-handed slepton-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)6">expected exclusion contour selectron-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)6">observed exclusion contour selectron-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)7">expected exclusion contour left-handed selectron-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)7">observed exclusion contour left-handed selectron-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)8">expected exclusion contour right-handed selectron-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)8">observed exclusion contour right-handed selectron-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)9">expected exclusion contour smuon-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)9">observed exclusion contour smuon-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)10">expected exclusion contour left-handed smuon-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)10">observed exclusion contour left-handed smuon-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(obs)11">expected exclusion contour right-handed smuon-pair production</a> <li><a href="89413?version=1&table=Exclusioncontour(exp)11">observed exclusion contour right-handed smuon-pair production</a> </ul> <b>Cross section upper limits:</b> <ul> <li><a href="89413?version=1&table=xsecupperlimits1">upper limits on signal cross section for direct chargino-pair production via W decay</a> <li><a href="89413?version=1&table=xsecupperlimits2">upper limits on signal cross section for direct chargino-pair production via slepton decay</a> <li><a href="89413?version=1&table=xsecupperlimits3">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=1&table=AcceptanceSR-DF-0J-[100,inf)forC1C1WWgrid">SR-DF-0J-[100,inf) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[160,inf)forC1C1WWgrid">SR-DF-0J-[160,inf) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[100,120)forC1C1WWgrid">SR-DF-0J-[100,120) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[120,160)forC1C1WWgrid">SR-DF-0J-[120,160) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[100,105)forC1C1WWgrid">SR-DF-0J-[100,105) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[105,110)forC1C1WWgrid">SR-DF-0J-[105,110) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[110,120)forC1C1WWgrid">SR-DF-0J-[110,120) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[120,140)forC1C1WWgrid">SR-DF-0J-[120,140) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[140,160)forC1C1WWgrid">SR-DF-0J-[140,160) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[160,180)forC1C1WWgrid">SR-DF-0J-[160,180) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[180,220)forC1C1WWgrid">SR-DF-0J-[180,220) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[220,260)forC1C1WWgrid">SR-DF-0J-[220,260) </a> <a href="89413?version=1&table=AcceptanceSR-DF-0J-[260,inf)forC1C1WWgrid">SR-DF-0J-[260,inf) </a><br/> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[100,inf)forC1C1WWgrid">SR-DF-1J-[100,inf) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[160,inf)forC1C1WWgrid">SR-DF-1J-[160,inf) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[100,120)forC1C1WWgrid">SR-DF-1J-[100,120) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[120,160)forC1C1WWgrid">SR-DF-1J-[120,160) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[100,105)forC1C1WWgrid">SR-DF-1J-[100,105) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[105,110)forC1C1WWgrid">SR-DF-1J-[105,110) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[110,120)forC1C1WWgrid">SR-DF-1J-[110,120) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[120,140)forC1C1WWgrid">SR-DF-1J-[120,140) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[140,160)forC1C1WWgrid">SR-DF-1J-[140,160) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[160,180)forC1C1WWgrid">SR-DF-1J-[160,180) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[180,220)forC1C1WWgrid">SR-DF-1J-[180,220) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[220,260)forC1C1WWgrid">SR-DF-1J-[220,260) </a> <a href="89413?version=1&table=AcceptanceSR-DF-1J-[260,inf)forC1C1WWgrid">SR-DF-1J-[260,inf) </a><br/> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[100,inf)forC1C1WWgrid">SR-SF-0J-[100,inf) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[160,inf)forC1C1WWgrid">SR-SF-0J-[160,inf) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[100,120)forC1C1WWgrid">SR-SF-0J-[100,120) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[120,160)forC1C1WWgrid">SR-SF-0J-[120,160) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[100,105)forC1C1WWgrid">SR-SF-0J-[100,105) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[105,110)forC1C1WWgrid">SR-SF-0J-[105,110) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[110,120)forC1C1WWgrid">SR-SF-0J-[110,120) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[120,140)forC1C1WWgrid">SR-SF-0J-[120,140) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[140,160)forC1C1WWgrid">SR-SF-0J-[140,160) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[160,180)forC1C1WWgrid">SR-SF-0J-[160,180) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[180,220)forC1C1WWgrid">SR-SF-0J-[180,220) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[220,260)forC1C1WWgrid">SR-SF-0J-[220,260) </a> <a href="89413?version=1&table=AcceptanceSR-SF-0J-[260,inf)forC1C1WWgrid">SR-SF-0J-[260,inf) </a><br/> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[100,inf)forC1C1WWgrid">SR-SF-1J-[100,inf) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[160,inf)forC1C1WWgrid">SR-SF-1J-[160,inf) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[100,120)forC1C1WWgrid">SR-SF-1J-[100,120) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[120,160)forC1C1WWgrid">SR-SF-1J-[120,160) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[100,105)forC1C1WWgrid">SR-SF-1J-[100,105) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[105,110)forC1C1WWgrid">SR-SF-1J-[105,110) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[110,120)forC1C1WWgrid">SR-SF-1J-[110,120) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[120,140)forC1C1WWgrid">SR-SF-1J-[120,140) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[140,160)forC1C1WWgrid">SR-SF-1J-[140,160) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[160,180)forC1C1WWgrid">SR-SF-1J-[160,180) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[180,220)forC1C1WWgrid">SR-SF-1J-[180,220) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[220,260)forC1C1WWgrid">SR-SF-1J-[220,260) </a> <a href="89413?version=1&table=AcceptanceSR-SF-1J-[260,inf)forC1C1WWgrid">SR-SF-1J-[260,inf) </a><br/> <li> <b>Efficiency</b> <br/> <a href="89413?version=1&table=EfficiencySR-DF-0J-[100,inf)forC1C1WWgrid">SR-DF-0J-[100,inf) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[160,inf)forC1C1WWgrid">SR-DF-0J-[160,inf) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[100,120)forC1C1WWgrid">SR-DF-0J-[100,120) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[120,160)forC1C1WWgrid">SR-DF-0J-[120,160) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[100,105)forC1C1WWgrid">SR-DF-0J-[100,105) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[105,110)forC1C1WWgrid">SR-DF-0J-[105,110) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[110,120)forC1C1WWgrid">SR-DF-0J-[110,120) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[120,140)forC1C1WWgrid">SR-DF-0J-[120,140) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[140,160)forC1C1WWgrid">SR-DF-0J-[140,160) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[160,180)forC1C1WWgrid">SR-DF-0J-[160,180) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[180,220)forC1C1WWgrid">SR-DF-0J-[180,220) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[220,260)forC1C1WWgrid">SR-DF-0J-[220,260) </a> <a href="89413?version=1&table=EfficiencySR-DF-0J-[260,inf)forC1C1WWgrid">SR-DF-0J-[260,inf) </a><br/> <a href="89413?version=1&table=EfficiencySR-DF-1J-[100,inf)forC1C1WWgrid">SR-DF-1J-[100,inf) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[160,inf)forC1C1WWgrid">SR-DF-1J-[160,inf) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[100,120)forC1C1WWgrid">SR-DF-1J-[100,120) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[120,160)forC1C1WWgrid">SR-DF-1J-[120,160) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[100,105)forC1C1WWgrid">SR-DF-1J-[100,105) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[105,110)forC1C1WWgrid">SR-DF-1J-[105,110) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[110,120)forC1C1WWgrid">SR-DF-1J-[110,120) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[120,140)forC1C1WWgrid">SR-DF-1J-[120,140) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[140,160)forC1C1WWgrid">SR-DF-1J-[140,160) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[160,180)forC1C1WWgrid">SR-DF-1J-[160,180) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[180,220)forC1C1WWgrid">SR-DF-1J-[180,220) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[220,260)forC1C1WWgrid">SR-DF-1J-[220,260) </a> <a href="89413?version=1&table=EfficiencySR-DF-1J-[260,inf)forC1C1WWgrid">SR-DF-1J-[260,inf) </a><br/> <a href="89413?version=1&table=EfficiencySR-SF-0J-[100,inf)forC1C1WWgrid">SR-SF-0J-[100,inf) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[160,inf)forC1C1WWgrid">SR-SF-0J-[160,inf) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[100,120)forC1C1WWgrid">SR-SF-0J-[100,120) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[120,160)forC1C1WWgrid">SR-SF-0J-[120,160) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[100,105)forC1C1WWgrid">SR-SF-0J-[100,105) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[105,110)forC1C1WWgrid">SR-SF-0J-[105,110) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[110,120)forC1C1WWgrid">SR-SF-0J-[110,120) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[120,140)forC1C1WWgrid">SR-SF-0J-[120,140) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[140,160)forC1C1WWgrid">SR-SF-0J-[140,160) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[160,180)forC1C1WWgrid">SR-SF-0J-[160,180) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[180,220)forC1C1WWgrid">SR-SF-0J-[180,220) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[220,260)forC1C1WWgrid">SR-SF-0J-[220,260) </a> <a href="89413?version=1&table=EfficiencySR-SF-0J-[260,inf)forC1C1WWgrid">SR-SF-0J-[260,inf) </a><br/> <a href="89413?version=1&table=EfficiencySR-SF-1J-[100,inf)forC1C1WWgrid">SR-SF-1J-[100,inf) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[160,inf)forC1C1WWgrid">SR-SF-1J-[160,inf) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[100,120)forC1C1WWgrid">SR-SF-1J-[100,120) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[120,160)forC1C1WWgrid">SR-SF-1J-[120,160) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[100,105)forC1C1WWgrid">SR-SF-1J-[100,105) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[105,110)forC1C1WWgrid">SR-SF-1J-[105,110) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[110,120)forC1C1WWgrid">SR-SF-1J-[110,120) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[120,140)forC1C1WWgrid">SR-SF-1J-[120,140) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[140,160)forC1C1WWgrid">SR-SF-1J-[140,160) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[160,180)forC1C1WWgrid">SR-SF-1J-[160,180) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[180,220)forC1C1WWgrid">SR-SF-1J-[180,220) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[220,260)forC1C1WWgrid">SR-SF-1J-[220,260) </a> <a href="89413?version=1&table=EfficiencySR-SF-1J-[260,inf)forC1C1WWgrid">SR-SF-1J-[260,inf) </a><br/> </ul> <b>Cutflow:</b> <ul> <li><a href="89413?version=1&table=Cutflow1">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=1&table=Cutflow1">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=1&table=Cutflow1">Cutflow for direct slepton-pair production $m(\tilde{l},\tilde{\chi}^{0}_1)=(400,200) GeV$</a> </ul> <b>Truth Code snippets</b> are 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.

Distributions of $m_{T2}$ in VR-top-low for data and the estimated SM backgrounds. The normalisation factors extracted from the corresponding CRs are used to rescale the $t\bar t$, single top, WW, WZ and ZZ backgrounds. The fake and non-prompt leptons background (FNP) is calculated using the data-driven matrix method. The uncertainty band includes all sources of systematic and statistical errors and the last bin includes the overflow.

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Measurement of $K_S^0$ and $\Lambda^0$ production in $t \bar{t}$ dileptonic events in $pp$ collisions at $\sqrt{s} =$ 7 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
No Journal Information, 2019.
Inspire Record 1746286 DOI 10.17182/hepdata.91243

Measurements of $K_S^0$ and $\Lambda^0$ production in $t\bar{t}$ final states have been performed. They are based on a data sample with integrated luminosity of 4.6 $\mathrm{fb}^{-1}$ from proton-proton collisions at a centre-of-mass energy of 7 TeV, collected in 2011 with the ATLAS detector at the Large Hadron Collider. Neutral strange particles are separated into three classes, depending on whether they are contained in a jet, with or without a $b$-tag, or not associated with a selected jet. The aim is to look for differences in their main kinematic distributions. A comparison of data with several Monte Carlo simulations using different hadronisation and fragmentation schemes, colour reconnection models and different tunes for the underlying event has been made. The production of neutral strange particles in $t\bar{t}$ dileptonic events is found to be well described by current Monte Carlo models for $K_S^0$ and $\Lambda^0$ production within jets, but not for those produced outside jets.

22 data tables

The transverse momentum ($p_{T}$) distribution for $K^{0}_{S}$ production inside $b$-jets for unfolded data to particle level, normalised to the total number of top pair dileptonic events and scaled to the bin width. The systematic uncertainties are, in order, due to; the MC modelling, the tracking inefficiencies, the jet energy scale (JES), the jet energy resolution (JER), out-of-fiducial events and the unfolding non-closure.

The energy fraction ($x_{K}$) distribution for $K^{0}_{S}$ production inside $b$-jets for unfolded data to particle level, normalised to the total number of top pair dileptonic events and scaled to the bin width. The systematic uncertainties are, in order, due to; the MC modelling, the tracking ineficiencies, the jet energy scale (JES), the jet energy resolution (JER), out-of-fiducial events and the unfolding non-closure.

The energy distribution for $K^{0}_{S}$ production inside $b$-jets for unfolded data to particle level, normalised to the total number of top pair dileptonic events and scaled to the bin width. The systematic uncertainties are, in order, due to; the MC modelling, the tracking ineficiencies, the jet energy scale (JES), the jet energy resolution (JER), out-of-fiducial events and the unfolding non-closure.

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Search for displaced vertices of oppositely charged leptons from decays of long-lived particles in $pp$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Inspire Record 1745920 DOI 10.17182/hepdata.90606

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 result is 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.

65 data tables

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.

Dependence of the overall signal efficiency on the pT of the long-lived Z' for Z' -> ee. The error bars indicate the total uncertainties.

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Measurement of the inclusive cross-section for the production of jets in association with a Z boson in proton-proton collisions at 8 TeV using the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
No Journal Information, 2019.
Inspire Record 1744201 DOI 10.17182/hepdata.90953

The inclusive cross-section for jet production in association with a Z boson decaying into an electron-positron pair is measured as a function of the transverse momentum and the absolute rapidity of jets using 19.9 fb$^{-1}$ of $\sqrt s = 8$ TeV proton-proton collision data collected with the ATLAS detector at the Large Hadron Collider. The measured Z + jets cross-section is unfolded to the particle level. The cross-section is compared with state-of-the-art Standard Model calculations, including the next-to-leading-order and next-to-next-to-leading-order perturbative QCD calculations, corrected for non-perturbative and QED radiation effects. The results of the measurements cover final-state jets with transverse momenta up to 1 TeV, and show good agreement with fixed-order calculations.

20 data tables

List of experimentally considered systematic uncertainties for the Z + jets cross-section measurement

The double-differential Z + jets production cross-section as a function of |y_{jet}| in the 25 GeV < p_{T}^{jet} < 50 GeV range. The particle level phase space definition: - 66 GeV < m_{ee} < 116 GeV - |eta_{electron}| < 2.47 - p_{T}^{electron} > 20 GeV - anti-kt R=0.4 jets N>=1 - |y_{jet}| < 3.4 - p_{T}^{jet} > 25 GeV - Delta R(jet, electron) > 0.4

The double-differential Z + jets production cross-section as a function of |y_{jet}| in the 50 GeV < p_{T}^{jet} < 100 GeV range. The particle level phase space definition: - 66 GeV < m_{ee} < 116 GeV - |eta_{electron}| < 2.47 - p_{T}^{electron} > 20 GeV - anti-kt R=0.4 jets N>=1 - |y_{jet}| < 3.4 - p_{T}^{jet} > 25 GeV - Delta R(jet, electron) > 0.4

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Observation of electroweak production of a same-sign $W$ boson pair in association with two jets in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2019.
Inspire Record 1738841 DOI 10.17182/hepdata.84643

This Letter presents the observation and measurement of electroweak production of a same-sign $W$ boson pair in association with two jets using 36.1 fb$^{-1}$ of proton-proton collision data recorded at a center-of-mass energy of $\sqrt{s}=13$ TeV by the ATLAS detector at the Large Hadron Collider. The analysis is performed in the detector fiducial phase-space region, defined by the presence of two same-sign leptons, electron or muon, and at least two jets with a large invariant mass and rapidity difference. A total of 122 candidate events are observed for a background expectation of $69 \pm 7$ events, corresponding to an observed signal significance of 6.5 standard deviations. The measured fiducial signal cross section is $\sigma^{\mathrm {fid.}}=2.89^{+0.51}_{-0.48} \mathrm{(stat.)} ^{+0.29}_{-0.28} \mathrm{(syst.)}$ fb.

6 data tables

Measured fiducial cross section.

The $m_{jj}$ distribution for events meeting all selection criteria for the signal region. Signal and individual background distributions are shown as predicted after the fit. The last bin includes the overflow. The highest value measured in a candidate event in data is $m_{jj}=3.8$ TeV.

The $m_{ll}$ distribution for events meeting all selection criteria for the signal region as predicted after the fit. The fitted signal strength and nuisance parameters have been propagated, with the exception of the uncertainties due to the interference and electroweak corrections for which a flat uncertainty is assigned. The last bin includes the overflow. The highest value measured in a candidate event in data is $m_{ll}=824$ GeV.

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Measurement of fiducial and differential $W^+W^-$ production cross-sections at $\sqrt{s}=$13 TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2019.
Inspire Record 1734263 DOI 10.17182/hepdata.89225

A measurement of fiducial and differential cross-sections for $W^+W^-$ production in proton-proton collisions at $\sqrt{s}=$13 TeV with the ATLAS experiment at the Large Hadron Collider using data corresponding to an integrated luminosity of $36.1$ fb$^{-1}$ is presented. Events with one electron and one muon are selected, corresponding to the decay of the diboson system as $WW\rightarrow e^{\pm}\nu\mu^{\mp}\nu$. To suppress top-quark background, events containing jets with a transverse momentum exceeding 35 GeV are not included in the measurement phase space. The fiducial cross-section, six differential distributions and the cross-section as a function of the jet-veto transverse momentum threshold are measured and compared with several theoretical predictions. Constraints on anomalous electroweak gauge boson self-interactions are also presented in the framework of a dimension-six effective field theory.

43 data tables

Measured fiducial cross-section as a function of the jet-veto $p_{T}$ threshold. The value at the jet-veto $p_{T}$ threshold of 35GeV corresponds to the nominal fiducial cross section measured in this publication.

Statistical correlation between bins in data for the measured fiducial cross-section as a function of the jet-veto $p_{T}$ threshold. The value at the jet-veto $p_{T}$ threshold of 35GeV corresponds to the nominal fiducial cross section measured in this publication.

Total correlation between bins in data for the measured fiducial cross-section as a function of the jet-veto $p_{T}$ threshold. The value at the jet-veto $p_{T}$ threshold of 35GeV corresponds to the nominal fiducial cross section measured in this publication.

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Measurement of the cross-section and charge asymmetry of $W$ bosons produced in proton-proton collisions at $\sqrt{s}=8$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Eur.Phys.J., 2019.
Inspire Record 1729240 DOI 10.17182/hepdata.89322

This paper presents measurements of the $W^+ \rightarrow \mu^+\nu$ and $W^- \rightarrow \mu^-\nu$ cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of $20.2~\mbox{fb$^{-1}$}$. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.

8 data tables

Cross-sections (differential in $\eta_{\mu}$) and asymmetry, as a function of $|\eta_{\mu}|$). The central values are provided along with the statistical and dominant systematic uncertainties: the data statistical uncertainty (Data Stat.), the $E_T^{\textrm{miss}}$ uncertainty, the uncertainties related to muon reconstruction (Muon Reco.), those related to the background, those from MC statistics (MC Stat.), and modelling uncertainties. The uncertainties of the cross-sections are given in percent and those of the asymmetry as an absolute difference from the nominal.

The correction factors, $C_{W^±,i}$ with their associated systematic uncertainties as a function of $|\eta_{\mu}|$, for $W^+$ and $W^−$

The integrated global correction factor $C_{W^±}$, for $W^+$ and $W^−$

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Evidence for the production of three massive vector bosons with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
No Journal Information, 2019.
Inspire Record 1726499 DOI 10.17182/hepdata.89323

A search for the production of three massive vector bosons in proton-proton collisions is performed using data at $\sqrt{s} = 13$ TeV recorded with the ATLAS detector at the Large Hadron Collider in the years 2015-2017, corresponding to an integrated luminosity of $79.8$ fb$^{-1}$. Events with two same-sign leptons $\ell$ (electrons or muons) and at least two reconstructed jets are selected to search for $WWW \to \ell \nu \ell \nu qq$. Events with three leptons without any same-flavour opposite-sign lepton pairs are used to search for $WWW \to \ell \nu \ell\nu \ell \nu$, while events with three leptons and at least one same-flavour opposite-sign lepton pair and one or more reconstructed jets are used to search for $WWZ \to \ell \nu qq \ell \ell$. Finally, events with four leptons are analysed to search for $WWZ \to \ell \nu \ell \nu \ell \ell$ and $WZZ \to qq \ell \ell \ell \ell$. Evidence for the joint production of three massive vector bosons is observed with a significance of 4.1 standard deviations, where the expectation is 3.1 standard deviations.

2 data tables

Measurement of the $WWW$ cross section.

Measurement of the $WWZ$ cross section.


Version 2
Search for heavy charged long-lived particles in the ATLAS detector in 36.1 fb$^{-1}$ of proton-proton collision data at $\sqrt{s} = 13$ TeV

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
Phys.Rev. D99 (2019) 092007, 2019.
Inspire Record 1718558 DOI 10.17182/hepdata.86565

A search for heavy charged long-lived particles is performed using a data sample of 36.1  fb−1 of proton-proton collisions at s=13  TeV collected by the ATLAS experiment at the Large Hadron Collider. The search is based on observables related to ionization energy loss and time of flight, which are sensitive to the velocity of heavy charged particles traveling significantly slower than the speed of light. Multiple search strategies for a wide range of lifetimes, corresponding to path lengths of a few meters, are defined as model independently as possible, by referencing several representative physics cases that yield long-lived particles within supersymmetric models, such as gluinos/squarks (R-hadrons), charginos and staus. No significant deviations from the expected Standard Model background are observed. Upper limits at 95% confidence level are provided on the production cross sections of long-lived R-hadrons as well as directly pair-produced staus and charginos. These results translate into lower limits on the masses of long-lived gluino, sbottom and stop R-hadrons, as well as staus and charginos of 2000, 1250, 1340, 430, and 1090 GeV, respectively.

30 data tables

Lower mass requirement for signal regions.

Lower mass requirement for signal regions.

Expected and observed events in the 16 discovery regions along with the according control regions.

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Measurement of the ratio of cross sections for inclusive isolated-photon production in $pp$ collisions at $\sqrt s = 13$ and $8$ TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
JHEP 1904 (2019) 093, 2019.
Inspire Record 1717495 DOI 10.17182/hepdata.89370

The ratio of the cross sections for inclusive isolated-photon production in pp collisions at centre-of-mass energies of 13 and 8 TeV is measured using the ATLAS detector at the LHC. The integrated luminosities of the 13 TeV and 8 TeV datasets are 3.2 fb$^{−1}$ and 20.2 fb$^{−1}$, respectively. The ratio is measured as a function of the photon transverse energy in different regions of the photon pseudorapidity. The predictions from next-to-leading-order perturbative QCD calculations are compared with the measured ratio. The experimental systematic uncertainties as well as the uncertainties affecting the predictions are evaluated taking into account the correlations between the two centre-of-mass energies, resulting in a reduction of up to a factor of 2.5 (5) in the experimental (theoretical) systematic uncertainties. The predictions based on several parameterisations of the proton parton distribution functions agree with the data within the reduced experimental and theoretical uncertainties. In addition, this ratio to that of the fiducial cross sections for Z boson production at 13 and 8 TeV using the decay channels Z → e$^{+}$e$^{−}$ and Z → μ$^{+}$μ$^{−}$ is made and compared with the theoretical predictions. In this double ratio, a further reduction of the experimental uncertainty is obtained because the uncertainties arising from the luminosity measurement cancel out. The predictions describe the measurements of the double ratio within the theoretical and experimental uncertainties.

16 data tables

Measured ratio of cross sections for inclusive isolated-photon production as a function of $E_{\rm T}^{\gamma}$ for $|\eta^{\gamma}|<0.6$.

Predicted ratio of cross sections for inclusive isolated-photon production as a function of $E_{\rm T}^{\gamma}$ for $|\eta^{\gamma}|<0.6$.

Measured ratio of cross sections for inclusive isolated-photon production as a function of $E_{\rm T}^{\gamma}$ for $0.6<|\eta^{\gamma}|<1.37$.

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Measurement of the $t\bar{t}Z$ and $t\bar{t}W$ cross sections in proton-proton collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
Phys.Rev. D99 (2019) 072009, 2019.
Inspire Record 1713423 DOI 10.17182/hepdata.88175

A measurement of the associated production of a top-quark pair (tt¯) with a vector boson (W, Z) in proton-proton collisions at a center-of-mass energy of 13 TeV is presented, using 36.1  fb-1 of integrated luminosity collected by the ATLAS detector at the Large Hadron Collider. Events are selected in channels with two same- or opposite-sign leptons (electrons or muons), three leptons or four leptons, and each channel is further divided into multiple regions to maximize the sensitivity of the measurement. The tt¯Z and tt¯W production cross sections are simultaneously measured using a combined fit to all regions. The best-fit values of the production cross sections are σtt¯Z=0.95±0.08stat±0.10syst  pb and σtt¯W=0.87±0.13stat±0.14syst  pb in agreement with the Standard Model predictions. The measurement of the tt¯Z cross section is used to set constraints on effective field theory operators which modify the tt¯Z vertex.

5 data tables

The result of the simultaneous fit to the $t\bar{t}Z$ and $t\bar{t}W$ cross sections.

68% confidence level (CL) contours of the measured $t\bar{t}Z$ and $t\bar{t}W$ cross sections.

95% confidence level (CL) contours of the measured $t\bar{t}Z$ and $t\bar{t}W$ cross sections.

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Search for chargino and neutralino production in final states with a Higgs boson and missing transverse momentum at $\sqrt{s} = 13$ TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
Phys.Rev., 2018.
Inspire Record 1711261 DOI 10.17182/hepdata.85726

A search is conducted for the electroweak pair production of a chargino and a neutralino $pp \rightarrow \tilde\chi^\pm_1 \tilde\chi^0_2$, where the chargino decays into the lightest neutralino and a $W$ boson, $\tilde\chi^\pm_1 \rightarrow \tilde\chi^0_1 W^{\pm}$, while the neutralino decays into the lightest neutralino and a Standard Model-like 125 GeV Higgs boson, $\tilde\chi^0_2 \rightarrow \tilde\chi^0_1 h$. Fully hadronic, semileptonic, diphoton, and multilepton (electrons, muons) final states with missing transverse momentum are considered in this search. Higgs bosons in the final state are identified by either two jets originating from bottom quarks ($h \rightarrow b\bar{b}$), two photons ($h \rightarrow \gamma\gamma$), or leptons from the decay modes $h \rightarrow WW$, $h \rightarrow ZZ$ or $h \rightarrow \tau \tau$. The analysis is based on 36.1 fb$^{-1}$ of $\sqrt{s} = 13$ TeV proton-proton collision data recorded by the ATLAS detector at the Large Hadron Collider. Observations are consistent with the Standard Model expectations, and 95% confidence-level limits of up to 680 GeV in $\tilde\chi^\pm_1/\tilde\chi^0_2$ mass are set in the context of a simplified supersymmetric model.

74 data tables

Data and SM predictions in SRs for the $0lb\bar{b}$ analysis for $E_{\mathrm{T}}^{\mathrm{miss}}$ in SRHad-High. All SRs selections but the one on the quantity shown are applied. All uncertainties are included in the uncertainty band. Two example SUSY models are superimposed for illustrative purposes.

Data and SM predictions in SRs for the $0lb\bar{b}$ analysis for $m_{b\bar{b}}$ in SRHad-Low. All SRs selections but the one on the quantity shown are applied. All uncertainties are included in the uncertainty band. Two example SUSY models are superimposed for illustrative purposes.

Data and SM predictions in SRs for the $1lb\bar{b}$ analysis for $m_{CT}$ in SR1Lbb-High. All SRs selections but the one on the quantity shown are applied. All uncertainties are included in the uncertainty band. Example SUSY models are superimposed for illustrative purposes.