829 research outputs found

    Techno-Functional properties of whey protein concentrates

    Get PDF
    Introduction. Whey proteins are well known for their nutritional value but also their functional properties because of their gelling and inter-facial properties. Objective. To extract whey protein concentrates and to study some techno-functional properties of these proteins. Material and methods. The whey proteins were obtained by thermo-precipitation. The techno-functional properties of these proteins (solubility, foaming and emulsification) were evaluated by comparison with bovine serum albumin (BSA). Results. The whey protein concentrates were soluble at pH 4 and 7. The foam expansion of whey proteins (7.00%) was significantly lower than that of BSA (73.33%) whereas the foam stability of whey proteins was significantly higher than that of BSA (p<0.01). The emulsifying properties of the whey protein concentrates were maximal at pH 4 and the emulsifying stability rating was maximal at pH 2. Conclusion. The whey protein concentrates are characterized by a very good solubility and an excellent emulsifying properties and foam stability. The whey proteins could also be useful in food manufacturing due to their functionalit

    Search for non-resonant Higgs boson pair production in the 2b+2l+ETmiss final state in pp collisions at s = 13 TeV with the ATLAS detector

    Get PDF
    A search for non-resonant Higgs boson pair (HH) production is presented, in which one of the Higgs bosons decays to a b-quark pair (bb ̄) and the other decays to WW*, ZZ*, or τ+τ−, with in each case a final state with l+l−+ neutrinos (l = e, μ). The analysis targets separately the gluon-gluon fusion and vector boson fusion production modes. Data recorded by the ATLAS detector in proton-proton collisions at a centre-of-mass energy of 13 TeV at the Large Hadron Collider, corresponding to an integrated luminosity of 140 fb−1, are used in this analysis. Events are selected to have exactly two b-tagged jets and two leptons with opposite electric charge and missing transverse momentum in the final state. These events are classified using multivariate analysis algorithms to separate the HH events from other Standard Model processes. No evidence of the signal is found. The observed (expected) upper limit on the cross-section for non-resonant Higgs boson pair production is determined to be 9.7 (16.2) times the Standard Model prediction at 95% confidence level. The Higgs boson self-interaction coupling parameter κλ and the quadrilinear coupling parameter κ2V are each separately constrained by this analysis to be within the ranges [−6.2, 13.3] and [−0.17, 2.4], respectively, at 95% confidence level, when all other parameters are fixed

    Determination of the Relative Sign of the Higgs Boson Couplings to W and Z Bosons Using WH Production via Vector-Boson Fusion with the ATLAS Detector

    Get PDF
    The associated production of Higgs and W bosons via vector-boson fusion is highly sensitive to the relative sign of the Higgs boson couplings to W and Z bosons. In this Letter, two searches for this process are presented, using 140 fb^{-1} of proton-proton collision data at sqrt[s]=13 TeV recorded by the ATLAS detector at the LHC. The first search targets scenarios with opposite-sign couplings of the W and Z bosons to the Higgs boson, while the second targets standard model-like scenarios with same-sign couplings. Both analyses consider Higgs boson decays into a pair of b quarks and W boson decays with an electron or muon. The data exclude the opposite-sign coupling hypothesis with a significance beyond 5σ, and the observed (expected) upper limit set on the cross section for vector-boson fusion WH production is 9.0 (8.7) times the standard model value at 95% confidence level

    Search for pair-produced higgsinos decaying via Higgs or Z bosons to final states containing a pair of photons and a pair of b-jets with the ATLAS detector

    Get PDF

    Search for top-philic heavy resonances in pp collisions at √s = 13 TeV with the ATLAS detector

    Get PDF
    A search for the associated production of a heavy resonance with a top-quark or a top-antitop-quark pair, and decaying into a tt ̄ pair is presented. The search uses the data recorded by the ATLAS detector in pp collisions at √s = 13 TeV at the Large Hadron Collider during the years 2015–2018, corresponding to an integrated luminosity of 139 fb−1. Events containing exactly one electron or muon are selected. The two hadronically decaying top quarks from the resonance decay are reconstructed using jets clustered with a large radius parameter of R = 1. The invariant mass spec&#x2;trum of the two top quark candidates is used to search for a resonance signal in the range of 1.0 TeV to 3.2 TeV. The pres&#x2;ence of a signal is examined using an approach with minimal model dependence followed by a model-dependent interpre&#x2;tation. No significant excess is observed over the background expectation. Upper limits on the production cross section times branching ratio at 95% confidence level are provided for a heavy Z&#x3; boson based on a simplified model, for Z&#x3; mass between 1.0 TeV and 3.0 TeV. The observed (expected) lim&#x2;its range from 21 (14) fb to 119 (86) fb depending on the choice of model parameter

    Azimuthal Angle Correlations of Muons Produced via Heavy-Flavor Decays in 5.02 TeV Pb + Pb and pp Collisions with the ATLAS Detector

    Get PDF

    Measurement of the polarisation of W bosons produced in top-quark decays using dilepton events at root s=13 TeV with the ATLAS experiment

    Get PDF
    A measurement of the polarisation of WW bosons produced in top-quark decays is presented, using proton-proton collision data at a centre-of-mass energy of s=13\sqrt{s} = 13 TeV. The data were collected by the ATLAS detector at the Large Hadron Collider and correspond to an integrated luminosity of 139 fb1^{-1}. The measurement is performed selecting ttˉt\bar{t} events decaying into final states with two charged leptons (electrons or muons) and at least two bb-tagged jets. The polarisation is extracted from the differential cross-section distribution of the cosθ\cos{\theta^{*}} variable, where θ\theta^{*} is the angle between the momentum direction of the charged lepton from the WW boson decay and the reversed momentum direction of the bb-quark from the top-quark decay, both calculated in the WW boson rest frame. Parton-level results, corrected for the detector acceptance and resolution, are presented for the cosθ\cos{\theta^{*}} angle. The measured fractions of longitudinal, left- and right-handed polarisation states are found to be f0=0.684±0.005(stat.)±0.014(syst.)f_{0} = 0.684 \pm 0.005\,\mathrm{(stat.)} \pm 0.014\,\mathrm{(syst.)}, fL=0.318±0.003(stat.)±0.008(syst.)f_{\mathrm{L}} = 0.318 \pm 0.003\,\mathrm{(stat.)} \pm 0.008\,\mathrm{(syst.)} and fR=0.002±0.002(stat.)±0.014(syst.)f_{\mathrm{R}} = -0.002 \pm 0.002\,\mathrm{(stat.)} \pm 0.014\,\mathrm{(syst.)}, in agreement with the Standard Model prediction

    Combination of searches for heavy spin-1 resonances using 139 fb−1 of proton-proton collision data at s = 13 TeV with the ATLAS detector

    Get PDF
    A combination of searches for new heavy spin-1 resonances decaying into different pairings of W, Z, or Higgs bosons, as well as directly into leptons or quarks, is presented. The data sample used corresponds to 139 fb−1 of proton-proton collisions at = 13 TeV collected during 2015–2018 with the ATLAS detector at the CERN Large Hadron Collider. Analyses selecting quark pairs (qq, bb, , and tb) or third-generation leptons (τν and ττ) are included in this kind of combination for the first time. A simplified model predicting a spin-1 heavy vector-boson triplet is used. Cross-section limits are set at the 95% confidence level and are compared with predictions for the benchmark model. These limits are also expressed in terms of constraints on couplings of the heavy vector-boson triplet to quarks, leptons, and the Higgs boson. The complementarity of the various analyses increases the sensitivity to new physics, and the resulting constraints are stronger than those from any individual analysis considered. The data exclude a heavy vector-boson triplet with mass below 5.8 TeV in a weakly coupled scenario, below 4.4 TeV in a strongly coupled scenario, and up to 1.5 TeV in the case of production via vector-boson fusion

    Search for pairs of muons with small displacements in pp collisions at root s=13 TeV with the ATLAS detector

    Get PDF
    A search for new phenomena giving rise to pairs of opposite electrically charged muons with impact parameters in the millimeter range is presented, using 139 fb−1 of √s = 13 TeV pp collision data from the ATLAS detector at the LHC. The search targets the gap in coverage between existing searches targeting final states with leptons with large displacement and prompt leptons. No significant excess over the background expectation is observed and exclusion limits are set on the mass of long-lived scalar supersymmetric muon-partners (smuons) with much lower lifetimes than previously targeted by displaced muon searches. Smuon lifetimes down to 1 ps are excluded for a smuon mass of 100 GeV, and smuon masses up to 520 GeV are excluded for a proper lifetime of 10 ps, at 95% confidence level. Finally, model-independent limits are set on the contribution from new phenomena to the signal-region yield
    corecore