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CERN-LHC. Search for the pair production of photon-jets---collimated groupings of photons---with the ATLAS detector. Highly collimated photon-jets can arise from the decay of new, highly boosted particles that can decay to multiple photons collimated enought to be identified in the electromagnetic calorimeter as a single, photon-like energy cluster. Data from proton–proton collisions at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 36.7 fb$^{-1}$, were collected in 2015 and 2016. Upper limits are placed on $\sigma\times \mathcal{B}(X\rightarrow aa)\times \mathcal{B}(a\rightarrow\gamma\gamma)^2$ and $\sigma\times \mathcal{B}(X\rightarrow aa)\times \mathcal{B}(a\rightarrow 3\pi^0)^2$ for 200 GeV < $m_X$ < 2TeV and $m_a$ < 10 GeV. Tables 8 to 35 are provided to allow the recasting of the cross-section upper limits to different signal models predicting final states with photon-jets. These tables present the selection efficiency (before categorisation) $\varepsilon_{\gamma_R}(E_\mathrm{T},\eta)$ for reconstructed photons originating from a photon-jet, and the fraction $f_{\gamma_R}(E_\mathrm{T},\eta)$ of reconstructed photons with a value of the shower shape variable $\Delta E$ lower than the threshold. The fiducial region is defined as: - $E_\mathrm{T,1}>0.4\times m_X$ - $E_\mathrm{T,2}>0.3\times m_X$ - $|\eta_i| < 2.37 (i=1,2)$ (excluding $1.37 < |\eta_i| <1.52$) where $E_\mathrm{T,1}, \eta_1$ ($E_\mathrm{T,2}, \eta_2$) are the transverse energy and the pseudorapidity of the $a$ particle with the higher (the lower) transverse energy, respectively. For a resonance particle $X$ decaying into a pair of photon-jets via $X\rightarrow aa$, the total selection efficiency, $\varepsilon$, and the fraction of events in the low-$\Delta E$ category, $f$, can be computed by integrating over the p.d.f. of $(E_\mathrm{T,1},\eta_1,E_\mathrm{T,2},\eta_2)$ with the following procedure: - apply the fiducial cuts to the two $a$ particles - compute $\varepsilon$ from the integration of $\varepsilon_{\gamma_R}(E_\mathrm{T,1},\eta_1) \cdot \varepsilon_{\gamma_R}(E_\mathrm{T,2},\eta_2)$ - compute $f$ from the integration of $\varepsilon_{\gamma_R}(E_\mathrm{T,1},\eta_1) \cdot \varepsilon_{\gamma_R}(E_\mathrm{T,2},\eta_2) \cdot f_{\gamma_R}(E_\mathrm{T,1},\eta_1) \cdot f_{\gamma_R}(E_\mathrm{T,2},\eta_2)$ divided by $\varepsilon$ With the resulting value of $f$ for a given value of $m_X$, the 95% CL observed upper limit on the visible cross-section (i.e. $\sigma\times \mathcal{B}\times\varepsilon$) can be taken from Table 7, which is considered to be model-independent. The corresponding upper limit on the cross-section times branching ratios, $\sigma \times \mathcal{B}$, can be computed by dividing the obtained visible cross-section by $\varepsilon$. The estimation procedure described above is validated by comparing the results for the benchmark signal scenario decaying via $X\rightarrow aa\rightarrow 4\gamma$ with the results presented in the paper (i.e. Table 3). It is found that the two results agree within 20%, and the result with the estimation procedure described above gives lower values. The main difference is found for large values of the mass ratio, $0.005 The expected upper limits on the production cross-section times the product of branching ratios for the benchmark signal scenario involving a scalar particle $X$ with narrow width decaying via $X\rightarrow aa\rightarrow 4\gamma$, $\sigma_X\times B(X\rightarrow aa)\times B(a\rightarrow\gamma\gamma)^2$. The limits for $m_{a}$ = 5 GeV and 10 GeV do not cover as large a range as the other mass points, since the region of interest is limited to $ m_{a} < 0.01 \times m_{X}$. Additionally, the expected limits are not provided for a small number of points, indicated with a hyphen, because of a technical failure with the computation.

for Pb+Pb, pT>0.2GeV, 40<=Nch<60, wo SRC, opposite pairs 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. Observed and expected background and signal effective mass distributions for SR2j-2000. For signal, a squark direct decay model where squarks have mass of 1200 GeV and the neutralino1 has mass of 0 GeV is shown.

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 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-2jB-1600.

Simulation of a black-hole binary system evolved by the SpEC code.

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-S2a.

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.

Exclusion curves 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 any leptons for a mass of 600 GeV. Grey numbers represent the expected upper cross-section limits. 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.