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CERN-LHC. A search for electroweak production of supersymmetric particles is performed in two-lepton and three-lepton final states using recursive jigsaw reconstruction. The search uses data collected in 2015 and 2016 by the ATLAS experiment in $\sqrt{s}$ = 13 TeV proton--proton collisions at the CERN Large Hadron Collider corresponding to an integrated luminosity of 36.1 $\textrm{fb}^{-1}$. Chargino--neutralino pair production, with decays via $W/Z$ bosons, is studied in final states involving leptons and jets and missing transverse momentum for scenarios with large and intermediate mass-splittings between the parent particle and lightest supersymmetric particle, as well as for the scenario where this mass splitting is close to the mass of the $Z$ boson. The latter case is challenging since the vector bosons are produced with kinematic properties that are similar to those in Standard Model processes. Results are found to be compatible with the Standard Model expectations in the signal regions targeting large and intermediate mass-splittings, and chargino--neutralino masses up to 600 GeV are excluded at 95% confidence level for a massless lightest supersymmetric particle. Excesses of data above the expected background are found in the signal regions targeting low mass-splittings, and the largest local excess amounts to 3.0 standard deviations. Distributions of kinematic variables in the signal regions for the $2\ell$ channels after applying all selection requirements. The histograms show the post-fit background predictions. The last bin includes the overflow. The distribution for $R_{\textrm{ISR}}$ in SR$2\ell$_ISR is plotted. The expected distribution for a benchmark signal model, normalized to the NLO+NLL cross-section times integrated luminosity, is also shown for comparison.

Measurements of the top--antitop quark pair production charge asymmetry in the dilepton channel are presented using data corresponding to an integrated luminosity of 20.3 $fb^{-1}$ from pp collisions at a center-of-mass energy of $\sqrt{s}=8\,$ TeV collected with the ATLAS detector at the Large Hadron Collider at CERN. Inclusive and differential measurements as a function of the invariant mass, transverse momentum, and longitudinal boost of the $t\bar{t}$ system are performed both in the full phase space and in a fiducial phase space closely matching the detector acceptance. Two observables are studied: $A_{ll}^{C}$ based on the selected leptons and $A_{t\bar{t}}^C$ based on the reconstructed $t\bar{t}$ final state. The inclusive asymmetries are measured in the full phase space to be $A_{ll}^{C} =0.008 \pm 0.006$ and $A_{t\bar{t}}^C = 0.021 \pm 0.016$, which are in agreement with the Standard Model predictions of $A_{ll}^{C} = 0.0064 \pm 0.0003$ and $A_{t\bar{t}}^C = 0.0111 \pm 0.0004$. The top-antitop inclusive asymmetry in the fiducial volume.

CERN-LHC. Experimental measurements of the correlations between the elliptic or triangular flow coefficients, $v_m$ ($m=2$ or 3), and other flow harmonics, $v_n$ ($n=2$ to 5) in lead-lead collisions. The data tables are linked to the corresponding figure number in the paper as well as additional plots in reference. $v_{4}$ data for various $q_2$ bins, Centrality 65-70%.

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 Meff-2j-1200.

CERN-LHC. Results of a search for new phenomena in events with an energetic photon and large missing transverse momentum with the ATLAS experiment at the LHC are reported. Data were collected in proton--proton collisions at a center-of-mass energy of 8 TeV and correspond to an integrated luminosity of 20.3 fb$^{-1}$. The observed data are well described by the expected Standard Model backgrounds. The expected (observed) upper limit on the fiducial cross section for the production of such events is 6.1 (5.3) fb at 95% confidence level. Exclusion limits are presented on models of new phenomena with large extra spatial dimensions, supersymmetric quarks, and direct pair production of dark-matter candidates. Limits at 90% C.L. on the EFT suppression scale M* as a function of the WIMP mass m_chi, for the tensor operator D9. Results where EFT truncation is applied are also shown, assuming coupling values sqrt(g_f g_chi)= 1, 4pi.

CERN-LHC. A search for additional heavy neutral Higgs bosons is performed using a data sample corresponding to an integrated luminosity of 139 fb$^{-1}$ from proton-proton collisions at $\sqrt{s}$ = 13 TeV recorded by the ATLAS detector at the LHC. The 1l1tau_h channel fiducial region is defined as: - 1e+>=1tau_h or 1mu+>=1tau_h - ptLepton > 30 GeV - |etaMuon| < 2.4, |etaEle| < 2.47 (excluding 1.37 < |etaEle| < 1.52) - ptTauVis > 25 GeV - |etaTauVis| < 2.3 (excluding 1.37 < |etaTauVis| < 1.52) - No events with more than 1 electron (ptEle > 15 GeV) or muon (ptMuon > 7 GeV, |etaMuon|<2.5) - If multiple tau_h exist, the leading visible pt one is chosen - l and tau_h opposite electric charge - |DeltaPhi(l,tau_h)| > 2.4 rad - mT(l,MET) < 40 GeV - veto 80 < m(l,tau_h) < 110 in 1e1tau_h channel The 2tau_h channel fiducial region is defined as: - >=2tau_h - ptTauVis > 65 GeV (at least one with ptTauVis > 130 GeV, note that technically, this upper threshold was 85 GeV for ~10% of the data) - No events with an electron or muon, ptLepton > 7 (15) GeV for muons (electrons), |etaMuon| < 2.5, |etaEle| < 2.47 (excluding 1.37 < |etaEle| < 1.52) - If more than two tau_h exist, the two leading visible pt ones are chosen - The two tau_h have opposite electric charge - |DeltaPhi(tau1_h,tau2_h)| > 2.7 rad For Higgs interpretations events entering the fiducial region of each channel are categorised as: - "b-tag: if they contain a b-quark initiated jet (ptJet > 20 GeV, |etaJet|<2.5)" - "b-veto: otherwise" Observed two dimensional likelihood scan of the gluon-gluon fusion cross section times branching fraction, $\sigma(gg\phi)\times B(\phi\to\tau\tau)$, vs the b-associated production times branching fraction, $\sigma(bb\phi)\times B(\phi\to\tau\tau)$ for the scalar boson mass ($m_\phi$) indicated in the table. For each mass, 10000 points are scanned. At each point $\Delta(\mathrm{NLL})$ is calculated, defined as the negative-log-likelihood (NLL) of the conditional fit with $\sigma(gg\phi)$ and $\sigma(bb\phi)$ fixed to their values at the point and with the minimum NLL value at any point subtracted. The best-fit point and the preferred 68% and 95% boundaries are found at $2\Delta(\mathrm{NLL})$ values of 0.0, 2.30 and 5.90, respectively. The value of $2\Delta(\mathrm{NLL})$ for 1000 GeV signal mass point is shown in the HEPData table.

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. Observed 95% CL upper limit on the signal cross-section from searches in a SUSY scenario where squarks are produced in pairs and decay via an intermediate lightest chargino to the lightest neutralino, $\tilde{q} \rightarrow q \tilde{\chi}_{1}^{\pm} \rightarrow q W^{\pm} \tilde{\chi}_{1}^{0}$.

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-C5.

CERN-LHC. Experimental measurements of the correlations between the elliptic or triangular flow coefficients, $v_m$ ($m=2$ or 3), and other flow harmonics, $v_n$ ($n=2$ to 5) in lead-lead collisions. The data tables are linked to the corresponding figure number in the paper as well as additional plots in reference. $v_{3}$ data for various $q_3$ bins, Centrality 0-5%.

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 Meff-2j-1600.