A search for electroweak production of supersymmetric particles in scenarios with compressed mass spectra in final states with two low-momentum leptons and missing transverse momentum is presented. This search uses pr...
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A search for electroweak production of supersymmetric particles in scenarios with compressed mass spectra in final states with two low-momentum leptons and missing transverse momentum is presented. This search uses proton-proton collision data recorded by the ATLAS detector at the Large Hadron Collider in 2015–2016, corresponding to 36.1 fb−1 of integrated luminosity at s=13 TeV. Events with same-flavor pairs of electrons or muons with opposite electric charge are selected. The data are found to be consistent with the Standard Model prediction. Results are interpreted using simplified models of R-parity-conserving supersymmetry in which there is a small mass difference between the masses of the produced supersymmetric particles and the lightest neutralino. Exclusion limits at 95% confidence level are set on next-to-lightest neutralino masses of up to 145 GeV for Higgsino production and 175 GeV for wino production, and slepton masses of up to 190 GeV for pair production of sleptons. In the compressed mass regime, the exclusion limits extend down to mass splittings of 2.5 GeV for Higgsino production, 2 GeV for wino production, and 1 GeV for slepton production. The results are also interpreted in the context of a radiatively-driven natural supersymmetry model with nonuniversal Higgs boson masses.
A search is presented for photonic signatures, motivated by generalized models of gauge-mediated supersymmetry breaking. This search makes use of proton-proton collision data at s=13 TeV corresponding to an integrate...
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A search is presented for photonic signatures, motivated by generalized models of gauge-mediated supersymmetry breaking. This search makes use of proton-proton collision data at s=13 TeV corresponding to an integrated luminosity of 36.1 fb−1 recorded by the ATLAS detector at the LHC, and it explores models dominated by both strong and electroweak production of supersymmetric partner states. Experimental signatures incorporating an isolated photon and significant missing transverse momentum are explored. These signatures include events with an additional photon or additional jet activity not associated with any specific underlying quark flavor. No significant excess of events is observed above the Standard Model prediction, and 95% confidence-level upper limits of between 0.083 and 0.32 fb are set on the visible cross section of contributions from physics beyond the Standard Model. These results are interpreted in terms of lower limits on the masses of gluinos, squarks, and gauginos in the context of generalized models of gauge-mediated supersymmetry, which reach as high as 2.3 TeV for strongly produced and 1.3 TeV for weakly produced supersymmetric partner pairs.
A search for the standard model Higgs boson produced in association with a top-quark pair, tt¯H, is presented. The analysis uses 36.1 fb−1 of pp collision data at s=13 TeV collected with the ATLAS detector at t...
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A search for the standard model Higgs boson produced in association with a top-quark pair, tt¯H, is presented. The analysis uses 36.1 fb−1 of pp collision data at s=13 TeV collected with the ATLAS detector at the Large Hadron Collider in 2015 and 2016. The search targets the H→bb¯ decay mode. The selected events contain either one or two electrons or muons from the top-quark decays, and are then categorized according to the number of jets and how likely these are to contain b-hadrons. Multivariate techniques are used to discriminate between signal and background events, the latter being dominated by tt¯+jets production. For a Higgs boson mass of 125 GeV, the ratio of the measured tt¯H signal cross-section to the standard model expectation is found to be μ=0.84−0.61+0.64. A value of μ greater than 2.0 is excluded at 95% confidence level (C.L.) while the expected upper limit is μ<1.2 in the absence of a tt¯H signal.
Software metrics are vital tools to enhance the quality of computer software, and to help in the control of software projects. Object-oriented technology is a new promising approach for developing software systems to ...
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Software metrics are vital tools to enhance the quality of computer software, and to help in the control of software projects. Object-oriented technology is a new promising approach for developing software systems to reduce software costs and to improve software productivity. Object-oriented metrics is a quantitative measure of the degree to which the software-system or component or process possess the given attribute. From the earliest days of the software engineering discipline there has been wide agreement of the need to measure software processes and products as a pre-condition for establishing control over development activities. Developing modules in a multi-suite environment would result in the problem of integration into a project. Software metrics are useful techniques to avoid this problem. The existing tools are not free of cost. The proposed project is to extract a general subset of these metrics for an object-oriented software development project and is to be of free of cost.
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 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.
ATLAS measurements of the production of muons from heavy-flavor decays in sNN=2.76 TeV Pb+Pb collisions and s=2.76 TeV pp collisions at the LHC are presented. Integrated luminosities of 0.14 nb−1 and 570 nb−1 are used...
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ATLAS measurements of the production of muons from heavy-flavor decays in sNN=2.76 TeV Pb+Pb collisions and s=2.76 TeV pp collisions at the LHC are presented. Integrated luminosities of 0.14 nb−1 and 570 nb−1 are used for the Pb+Pb and pp measurements, respectively, which are performed over the muon transverse momentum range 4
A measurement of the rapidity and transverse momentum dependence of dijet azimuthal decorrelations is presented, using the quantity RΔϕ. The quantity RΔϕ specifies the fraction of the inclusive dijet events in which...
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A measurement of the rapidity and transverse momentum dependence of dijet azimuthal decorrelations is presented, using the quantity RΔϕ. The quantity RΔϕ specifies the fraction of the inclusive dijet events in which the azimuthal opening angle of the two jets with the highest transverse momenta is less than a given value of the parameter Δϕmax. The quantity RΔϕ is measured in proton-proton collisions at s=8 TeV as a function of the dijet rapidity interval, the event total scalar transverse momentum, and Δϕmax. The measurement uses an event sample corresponding to an integrated luminosity of 20.2 fb−1 collected with the ATLAS detector at the CERN Large Hadron Collider. Predictions of a perturbative QCD calculation at next-to-leading order in the strong coupling with corrections for nonperturbative effects are compared to the data. The theoretical predictions describe the data in the whole kinematic region. The data are used to determine the strong coupling αS and to study its running for momentum transfers from 260 GeV to above 1.6 TeV. Analysis that combines data at all momentum transfers results in αS(mZ)=0.1127−0.0027+0.0063.
High-quality algorithms for dense optical flow computation are computationally intensive. To compute them with high speed and low power is vital to make optical flow computation applicable in real-world applications. ...
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ISBN:
(纸本)9781479962464
High-quality algorithms for dense optical flow computation are computationally intensive. To compute them with high speed and low power is vital to make optical flow computation applicable in real-world applications. In contrast to only the Horn-Schunck model being studied on FPGA-based systems today, one of the best linear variational methods for dense optical flow computation, Combine-Brightness-Gradient, is implemented on FPGA-accelerated heterogeneous platforms in this paper. C instead of HDLs is employed and optimizing techniques based on the algorithmic parallelism and hardware architecture are introduced. Experimental results show that 30-110x improvement of the computing efficiency over CPUs was achieved. The FPGA-accelerated version is able to process 640 × 480 image at 12 fps with 0.38 J per frame, while it is 0.8 fps and around 40 J on CPUs. Through demonstrating high performance and low power of dense optical flow algorithm on FPGA-based heterogeneous platforms implemented in C, this paper shows that the off-the-shelf commodity FPGAs coupled with High-Level-Synthesis (HLS) tools could provide an available option when computational efficiency together with development speed are required.
The sentiment mining is a fast growing topic of both academic research and commercial applications, especially with the widespread of short-text applications on the Web. A fundamental problem that confronts sentiment ...
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ISBN:
(纸本)9781479967162
The sentiment mining is a fast growing topic of both academic research and commercial applications, especially with the widespread of short-text applications on the Web. A fundamental problem that confronts sentiment mining is the automatics and correctness of mined sentiment. This paper proposes an DLDA (Double Latent Dirichlet Allocation) model to analyze sentiment for short-texts based on topic model. Central to DLDA is to add sentiment to topic model and consider sentiment as equal to topic, but independent of topic. DLDA is actually two methods DLDA I and its improvement DLDA II. Compared to the single topic-word LDA, the double LDA I, i.e., DLDA I designs another sentiment-word LDA. Both LDAs are independent of each other, but they combine to influence the selected words in short-texts. DLDA II is an improvement of DLDA I. It employs entropy formula to assign weights of words in the Gibbs sampling based on the ideas that words with stronger sentiment orientation should be assigned with higher weights. Experiments show that compared with other traditional topic methods, both DLDA I and II can achieve higher accuracy with less manual needs.
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