Due to the strict energy limitation and the common vulnerability of WSNs, providing efficient and security data gathering in WSNs becomes an essential problem. Compressive data gathering, which is based on the recent ...
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Running MapReduce in a shared cluster has become a recent trend to process large-scale data analytical applications while improving the cluster utilization. However, the network sharing among various applications can ...
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Silicosis remains one of the most harmful occupational respiratory diseases. It threatens the workers exposed to dust environment. Chest radiograph is the main available image source for silicosis diagnosis according ...
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A search for direct pair production of top squarks in final states with two tau leptons, b-jets, and missing transverse momentum is presented. The analysis is based on proton-proton collision data at s=13 TeV corresp...
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A search for direct pair production of top squarks in final states with two tau leptons, b-jets, and missing transverse momentum is presented. The analysis is based on proton-proton collision data at s=13 TeV corresponding to an integrated luminosity of 36.1 fb−1 recorded with the ATLAS detector at the Large Hadron Collider in 2015 and 2016. Two exclusive channels with either two hadronically decaying tau leptons or one hadronically and one leptonically decaying tau lepton are considered. No significant deviation from the Standard Model predictions is observed in the data. The analysis results are interpreted in terms of model-independent limits and used to derive exclusion limits on the masses of the top squark t˜1 and the tau slepton τ˜1 in a simplified model of supersymmetry with a nearly massless gravitino. In this model, masses up to m(t˜1)=1.16 TeV and m(τ˜1)=1.00 TeV are excluded at 95% confidence level.
A detailed study of multiparticle azimuthal correlations is presented using pp data at s=5.02 and 13 TeV, and p+Pb data at sNN=5.02 TeV, recorded with the ATLAS detector at the CERN Large Hadron Collider. The azimutha...
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A detailed study of multiparticle azimuthal correlations is presented using pp data at s=5.02 and 13 TeV, and p+Pb data at sNN=5.02 TeV, recorded with the ATLAS detector at the CERN Large Hadron Collider. The azimuthal correlations are probed using four-particle cumulants cn{4} and flow coefficients vn{4}=(−cn{4})1/4 for n=2 and 3, with the goal of extracting long-range multiparticle azimuthal correlation signals and suppressing the short-range correlations. The values of cn{4} are obtained as a function of the average number of charged particles per event, Nch, using the recently proposed two-subevent and three-subevent cumulant methods, and compared with results obtained with the standard cumulant method. The standard method is found to be strongly biased by short-range correlations, which originate mostly from jets with a positive contribution to cn{4}. The three-subevent method, on the other hand, is found to be least sensitive to short-range correlations. The three-subevent method gives a negative c2{4}, and therefore a well-defined v2{4}, nearly independent of Nch, which implies that the long-range multiparticle azimuthal correlations persist to events with low multiplicity. Furthermore, v2{4} is found to be smaller than the v2{2} measured using the two-particle correlation method, as expected for long-range collective behavior. Finally, the measured values of v2{4} and v2{2} are used to estimate the number of sources relevant for the initial eccentricity in the collision geometry. The results based on the subevent cumulant technique provide direct evidence, in small collision systems, for a long-range collectivity involving many particles distributed across a broad rapidity interval.
A search for pair production of the supersymmetric partners of the Higgs boson (higgsinos H˜) in gauge-mediated scenarios is reported. Each higgsino is assumed to decay to a Higgs boson and a gravitino. Two complement...
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A search for pair production of the supersymmetric partners of the Higgs boson (higgsinos H˜) in gauge-mediated scenarios is reported. Each higgsino is assumed to decay to a Higgs boson and a gravitino. Two complementary analyses, targeting high- and low-mass signals, are performed to maximize sensitivity. The two analyses utilize LHC pp collision data at a center-of-mass energy s=13 TeV, the former with an integrated luminosity of 36.1 fb−1 and the latter with 24.3 fb−1, collected with the ATLAS detector in 2015 and 2016. The search is performed in events containing missing transverse momentum and several energetic jets, at least three of which must be identified as b-quark jets. No significant excess is found above the predicted background. Limits on the cross section are set as a function of the mass of the H˜ in simplified models assuming production via mass-degenerate higgsinos decaying to a Higgs boson and a gravitino. Higgsinos with masses between 130 and 230 GeV and between 290 and 880 GeV are excluded at the 95% confidence level. Interpretations of the limits in terms of the branching ratio of the higgsino to a Z boson or a Higgs boson are also presented, and a 45% branching ratio to a Higgs boson is excluded for mH˜≈400 GeV.
Properties of the Higgs boson are measured in the two-photon final state using 36.1 fb−1 of proton–proton collision data recorded at s=13 TeV by the ATLAS experiment at the Large Hadron Collider. Cross-section meas...
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Properties of the Higgs boson are measured in the two-photon final state using 36.1 fb−1 of proton–proton collision data recorded at s=13 TeV by the ATLAS experiment at the Large Hadron Collider. Cross-section measurements for the production of a Higgs boson through gluon–gluon fusion, vector-boson fusion, and in association with a vector boson or a top-quark pair are reported. The signal strength, defined as the ratio of the observed to the expected signal yield, is measured for each of these production processes as well as inclusively. The global signal strength measurement of 0.99±0.14 improves on the precision of the ATLAS measurement at s=7 and 8 TeV by a factor of two. Measurements of gluon–gluon fusion and vector-boson fusion productions yield signal strengths compatible with the Standard Model prediction. Measurements of simplified template cross sections, designed to quantify the different Higgs boson production processes in specific regions of phase space, are reported. The cross section for the production of the Higgs boson decaying to two isolated photons in a fiducial region closely matching the experimental selection of the photons is measured to be 55±10 fb, which is in good agreement with the Standard Model prediction of 64±2 fb. Furthermore, cross sections in fiducial regions enriched in Higgs boson production in vector-boson fusion or in association with large missing transverse momentum, leptons or top-quark pairs are reported. Differential and double-differential measurements are performed for several variables related to the diphoton kinematics as well as the kinematics and multiplicity of the jets produced in association with a Higgs boson. These differential cross sections are sensitive to higher order QCD corrections and properties of the Higgs boson, such as its spin and CP quantum numbers. No significant deviations from a wide array of Standard Model predictions are observed. Finally, the strength and tensor structure of the Higgs boson
Results from a search for supersymmetry in events with four or more charged leptons (electrons, muons and taus) are presented. The analysis uses a data sample corresponding to 36.1 fb−1 of proton–proton collisions d...
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Results from a search for supersymmetry in events with four or more charged leptons (electrons, muons and taus) are presented. The analysis uses a data sample corresponding to 36.1 fb−1 of proton–proton collisions delivered by the Large Hadron Collider at s=13 TeV and recorded by the ATLAS detector. Four-lepton signal regions with up to two hadronically decaying taus are designed to target a range of supersymmetric scenarios that can be either enriched in or depleted of events involving the production and decay of a Z boson. Data yields are consistent with Standard Model expectations and results are used to set upper limits on the event yields from processes beyond the Standard Model. Exclusion limits are set at the 95% confidence level in simplified models of general gauge mediated supersymmetry, where Higgsino masses are excluded up to 295 GeV. In R-parity-violating simplified models with decays of the lightest supersymmetric particle to charged leptons, lower limits of 1.46, 1.06, and 2.25 TeV are placed on wino, slepton and gluino masses, respectively.
Many extensions of the Standard Model predict new resonances decaying to a Z, W, or Higgs boson and a photon. This paper presents a search for such resonances produced in pp collisions at s=13 TeV using a data set wi...
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Many extensions of the Standard Model predict new resonances decaying to a Z, W, or Higgs boson and a photon. This paper presents a search for such resonances produced in pp collisions at s=13 TeV using a data set with an integrated luminosity of 36.1 fb−1 collected by the ATLAS detector at the LHC. The Z/W/H bosons are identified through their decays to hadrons. The data are found to be consistent with the Standard Model expectation in the entire investigated mass range. Upper limits are set on the production cross section times branching fraction for resonance decays to Z/W+γ in the mass range from 1.0 to 6.8 TeV and for the first time into H+γ in the mass range from 1.0 to 3.0 TeV.
A search for the associated production of the Higgs boson with a top quark pair (tt¯H) is reported. The search is performed in multilepton final states using a data set corresponding to an integrated luminosity o...
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A search for the associated production of the Higgs boson with a top quark pair (tt¯H) is reported. The search is performed in multilepton final states using a data set corresponding to an integrated luminosity of 36.1 fb−1 of proton-proton collision data recorded by the ATLAS experiment at a center-of-mass energy s=13 TeV at the Large Hadron Collider. Higgs boson decays to WW*, ττ, and ZZ* are targeted. Seven final states, categorized by the number and flavor of charged-lepton candidates, are examined for the presence of the Standard Model Higgs boson with a mass of 125 GeV and a pair of top quarks. An excess of events over the expected background from Standard Model processes is found with an observed significance of 4.1 standard deviations, compared to an expectation of 2.8 standard deviations. The best fit for the tt¯H production cross section is σ(tt¯H)=790−210+230 fb, in agreement with the Standard Model prediction of 507−50+35 fb. The combination of this result with other tt¯H searches from the ATLAS experiment using the Higgs boson decay modes to bb¯, γγ and ZZ*→4ℓ, has an observed significance of 4.2 standard deviations, compared to an expectation of 3.8 standard deviations. This provides evidence for the tt¯H production mode.
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