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CERN-LHC. Many extensions of the Standard Model posit the existence of heavy particles with long lifetimes. This article presents the results of a search for events containing at least one long-lived particle that decays at a significant distance from its production point into two leptons or into five or more charged particles. This analysis uses a data sample of proton-proton collisions at $\sqrt{s}$ = 8 TeV corresponding to an integrated luminosity of 20.3 fb$^{-1}$ collected in 2012 by the ATLAS detector operating at the Large Hadron Collider. No events are observed in any of the signal regions, and limits are set on model parameters within supersymmetric scenarios involving R-parity violation, split supersymmetry, and gauge mediation. In some of the search channels, the trigger and search strategy are based only on the decay products of individual long-lived particles, irrespective of the rest of the event. In these cases, the provided limits can easily be reinterpreted in different scenarios. Upper limits (95% CL) from the DV+$E_T^{miss}$ channel on the production cross-section and the corresponding event-level efficiencies (from Auxiliary Figure 9a) for two GGM SUSY models as a function of the $\tilde{\chi}_1^0$ proper decay distance $c\tau$. The models consider gluino pair production, with $\tilde{g}\to qq[\tilde{\chi}_1^0\to Z\tilde{G}]$ decays, $m(\tilde{g})$ = 1100 GeV and a $\tilde{\chi}_1^0$ mass in GeV as indicated. For comparison, the production cross-section for $m(\tilde{g})$ = 1100 GeV is $7.6\pm2.8$ fb.

CERN-LHC. A search for the supersymmetric partners of quarks and gluons (squarks and gluinos) in final states containing hadronic jets and missing transverse momentum, but no electrons or muons, is presented. The data used in this search were recorded in 2015 and 2016 by the ATLAS experiment in $\sqrt{s}=13\mathrm{\ Te\kern -0.1em V}$ proton--proton collisions at the Large Hadron Collider, corresponding to an integrated luminosity of 36.1 fb$^{-1}$. The results are interpreted in the context of various models where squarks and gluinos are pair-produced and the neutralino is the lightest supersymmetric particle. An exclusion limit at the 95% confidence level on the mass of the gluino is set at 2.03$\mathrm{\ Te\kern -0.1em V}$ for a simplified model incorporating only a gluino and the lightest neutralino, assuming the lightest neutralino is massless. For a simplified model involving the strong production of mass-degenerate first- and second-generation squarks, squark masses below 1.55$\mathrm{\ Te\kern -0.1em V}$ are excluded if the lightest neutralino is massless. These limits substantially extend the region of supersymmetric parameter space previously excluded by searches with the ATLAS detector. Signal region efficiency for simplified model with squark pair production and direct decays to a quark and neutralino in SR RJR-C2.

The combined $\tilde\chi^{\pm}_{1}\tilde\chi^{\mp}_{1} + \tilde\chi^{\pm}_{1}\tilde\chi^{0}_{1}$ reconstruction efficiencies in the SRFR region. Results are given as a function of $\tilde\chi^{\pm}_{1}/\tilde\chi^{0}_{1}$ mass and branching fraction to Z bosons, and are derived separately when requiring that the charged-lepton decays of $\tilde\chi^{\pm}_{1}/\tilde\chi^{0}_{1}$ are into electrons only No data abstract available.

CERN-LHC. A search for the supersymmetric partners of quarks and gluons (squarks and gluinos) in final states containing hadronic jets and missing transverse momentum, but no electrons or muons, is presented. The data used in this search were recorded in 2015 and 2016 by the ATLAS experiment in $\sqrt{s}=13\mathrm{\ Te\kern -0.1em V}$ proton--proton collisions at the Large Hadron Collider, corresponding to an integrated luminosity of 36.1 fb$^{-1}$. The results are interpreted in the context of various models where squarks and gluinos are pair-produced and the neutralino is the lightest supersymmetric particle. An exclusion limit at the 95% confidence level on the mass of the gluino is set at 2.03$\mathrm{\ Te\kern -0.1em V}$ for a simplified model incorporating only a gluino and the lightest neutralino, assuming the lightest neutralino is massless. For a simplified model involving the strong production of mass-degenerate first- and second-generation squarks, squark masses below 1.55$\mathrm{\ Te\kern -0.1em V}$ are excluded if the lightest neutralino is massless. These limits substantially extend the region of supersymmetric parameter space previously excluded by searches with the ATLAS detector. Signal region acceptance for simplified model with squark pair production and direct decays to a quark and neutralino in SR Meff-2j-1600.

Exclusion curve for the simplified model of $\tilde\chi^{\pm}_{1}\tilde\chi^{\mp}_{1} + \tilde\chi^{0}_{1}\tilde\chi^{0}_{1}$ pair-production as a function of $\tilde\chi^{\pm}_{1}/\tilde\chi^{0}_{1}$ branching fraction to $Z$ and Higgs bosons. Results are shown for the charged-lepton decays of $\tilde\chi^{\pm}_{1}/\tilde\chi^{0}_{1}$ into electrons only for a mass of 700 GeV. The expected 95% CL exclusion (dashed black line) is shown with $\pm1~\sigma_{\mathrm{exp}}$ (yellow band) from systematic and statistical uncertainties on the expected yields. The observed 95% CL exclusion (solid red line) is shown with the $\pm1~\sigma_{\mathrm{theory}}^{\mathrm{SUSY}}$ (dotted red line) from signal cross section uncertainties on the signal models. The phase-space excluded by the search is shown in the shaded color. No data abstract available.

CERN-LHC. A search for the supersymmetric partners of quarks and gluons (squarks and gluinos) in final states containing hadronic jets and missing transverse momentum, but no electrons or muons, is presented. The data used in this search were recorded in 2015 and 2016 by the ATLAS experiment in $\sqrt{s}=13\mathrm{\ Te\kern -0.1em V}$ proton--proton collisions at the Large Hadron Collider, corresponding to an integrated luminosity of 36.1 fb$^{-1}$. The results are interpreted in the context of various models where squarks and gluinos are pair-produced and the neutralino is the lightest supersymmetric particle. An exclusion limit at the 95% confidence level on the mass of the gluino is set at 2.03$\mathrm{\ Te\kern -0.1em V}$ for a simplified model incorporating only a gluino and the lightest neutralino, assuming the lightest neutralino is massless. For a simplified model involving the strong production of mass-degenerate first- and second-generation squarks, squark masses below 1.55$\mathrm{\ Te\kern -0.1em V}$ are excluded if the lightest neutralino is massless. These limits substantially extend the region of supersymmetric parameter space previously excluded by searches with the ATLAS detector. Signal region efficiency for simplified model with squark pair production and decays to a quark and chargino in SR RJR-C4.

CERN-LHC. Results of a search for decays of massive particles to fully hadronic final states are presented. This search uses 20.3 fb$^{-1}$ of data collected by the ATLAS detector in $\sqrt{s} = 8$ TeV proton--proton collisions at the LHC. Signatures based on high jet multiplicities without requirements on the missing transverse momentum are used to search for $R$-parity-violating supersymmetric gluino pair production with subsequent decays to quarks. The analysis is performed using a requirement on the number of jets, in combination with separate requirements on the number of b-tagged jets, as well as a topological observable formed from the scalar sum of the mass values of large-radius jets in the event. Results are interpreted in the context of all possible branching ratios of direct gluino decays to various quark flavors. No significant deviation is observed from the expected Standard Model backgrounds estimated using jet-counting as well as data-driven templates of the total-jet-mass spectra. Gluino pair decays to ten or more quarks via intermediate neutralinos are excluded for a gluino with mass $m_{\tilde{g}} < 1$ TeV for a neutralino mass $m_{\tilde{\chi}^0_1} = 500$ GeV. Direct gluino decays to six quarks are excluded for $m_{\tilde{g}} < 917$ GeV for light-flavor final states, and results for various flavor hypotheses are presented. Observed cross-section exclusion in units of pb at 95% C.L., in the gluino/neutralino mass plane, for the merged analysis, when SR100 is used for each mass point.

Exclusion curve for the simplified model of $\tilde\chi^{\pm}_{1}\tilde\chi^{\mp}_{1} + \tilde\chi^{0}_{1}\tilde\chi^{0}_{1}$ pair-production as a function of $\tilde\chi^{\pm}_{1}/\tilde\chi^{0}_{1}$ branching fraction to $Z$ and Higgs bosons. Results are shown for the charged-lepton decays of $\tilde\chi^{\pm}_{1}/\tilde\chi^{0}_{1}$ into muons only for a mass of 700 GeV. The expected 95% CL exclusion (dashed black line) is shown with $\pm1~\sigma_{\mathrm{exp}}$ (yellow band) from systematic and statistical uncertainties on the expected yields. The observed 95% CL exclusion (solid red line) is shown with the $\pm1~\sigma_{\mathrm{theory}}^{\mathrm{SUSY}}$ (dotted red line) from signal cross section uncertainties on the signal models. The phase-space excluded by the search is shown in the shaded color. No data abstract available.

CERN-LHC. A study of events in proton-proton collisions at a centre-of-mass energy of 7 TeV characterised by having large missing transverse momentum, jets and at least two tau leptons from a data sample of integrated luminosity 2 fb-1. The analysis finds no excesses above the Standard Model and presents lower limits on the GMSB breaking scale, Lambda, and the ratio of the vacuum expectation values of the two Higgs doublets, tan(beta). Data on the acceptances and efficiencies are given here taken from the auxilliary material linked below. The observed 95% CL limits on the minimal GMSB model parameters Lambda and tan(beta) over the tan(beta) region 42.8 to 48.8.

CERN-LHC. A search for the supersymmetric partners of quarks and gluons (squarks and gluinos) in final states containing hadronic jets and missing transverse momentum, but no electrons or muons, is presented. The data used in this search were recorded in 2015 and 2016 by the ATLAS experiment in $\sqrt{s}=13\mathrm{\ Te\kern -0.1em V}$ proton--proton collisions at the Large Hadron Collider, corresponding to an integrated luminosity of 36.1 fb$^{-1}$. The results are interpreted in the context of various models where squarks and gluinos are pair-produced and the neutralino is the lightest supersymmetric particle. An exclusion limit at the 95% confidence level on the mass of the gluino is set at 2.03$\mathrm{\ Te\kern -0.1em V}$ for a simplified model incorporating only a gluino and the lightest neutralino, assuming the lightest neutralino is massless. For a simplified model involving the strong production of mass-degenerate first- and second-generation squarks, squark masses below 1.55$\mathrm{\ Te\kern -0.1em V}$ are excluded if the lightest neutralino is massless. These limits substantially extend the region of supersymmetric parameter space previously excluded by searches with the ATLAS detector. Signal region efficiency for simplified model with gluino pair production and direct decays to two quarks and neutralino in SR RJR-S3a.