343 results match your criteria: "B.I. Stepanov Institute of Physics[Affiliation]"

A search for high-mass resonances decaying to τν using proton-proton collisions at sqrt[s]=13  TeV produced by the Large Hadron Collider is presented. Only τ-lepton decays with hadrons in the final state are considered. The data were recorded with the ATLAS detector and correspond to an integrated luminosity of 36.

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Porphyrins and flavins as endogenous acceptors of optical radiation of blue spectral region determining photoinactivation of microbial cells.

J Photochem Photobiol B

June 2018

Republican Manufacturing Unitary Enterprise Academpharm, 220141 Minsk, Kuprevich st. 5/3, Belarus.

Article Synopsis
  • Laser radiation in the blue spectral region (405 and 445 nm) inhibits the growth of Staphylococcus aureus, E. coli, and Candida albicans without needing added photosensitizers.
  • Flavin compounds and endogenous metal-free porphyrins are identified as key contributors to the antimicrobial effect by sensitizing the formation of reactive oxygen species when exposed to blue light.
  • Fluorescence intensity of porphyrins decreases significantly when moving from 405 nm to 445 nm, while their antimicrobial effectiveness decreases only slightly, indicating a complex interplay between different photosensitizers based on microbial cell type.
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This paper presents a direct measurement of the decay width of the top quark using events in the lepton+jets final state. The data sample was collected by the ATLAS detector at the LHC in proton-proton collisions at a centre-of-mass energy of 8 TeV and corresponds to an integrated luminosity of 20.2 fb .

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A search is performed for new phenomena in events having a photon with high transverse momentum and a jet collected in of proton-proton collisions at a centre-of-mass energy of = 13 TeV recorded with the ATLAS detector at the Large Hadron Collider. The invariant mass distribution of the leading photon and jet is examined to look for the resonant production of new particles or the presence of new high-mass states beyond the Standard Model. No significant deviation from the background-only hypothesis is observed and cross-section limits for generic Gaussian-shaped resonances are extracted.

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A search for neutral heavy resonances is performed in the decay channel using collision data corresponding to an integrated luminosity of , collected at a centre-of-mass energy of 13 by the ATLAS detector at the Large Hadron Collider. No evidence of such heavy resonances is found. In the search for production via the quark-antiquark annihilation or gluon-gluon fusion process, upper limits on as a function of the resonance mass are obtained in the mass range between 200 and up to 5 for various benchmark models: a Higgs-like scalar in different width scenarios, a two-Higgs-doublet model, a heavy vector triplet model, and a warped extra dimensions model.

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A search for doubly charged Higgs bosons with pairs of prompt, isolated, highly energetic leptons with the same electric charge is presented. The search uses a proton-proton collision data sample at a centre-of-mass energy of 13 TeV corresponding to 36.1 of integrated luminosity recorded in 2015 and 2016 by the ATLAS detector at the LHC.

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A measurement of the mass of the boson is presented based on proton-proton collision data recorded in 2011 at a centre-of-mass energy of 7 TeV with the ATLAS detector at the LHC, and corresponding to of integrated luminosity. The selected data sample consists of candidates in the channel and candidates in the channel. The -boson mass is obtained from template fits to the reconstructed distributions of the charged lepton transverse momentum and of the boson transverse mass in the electron and muon decay channels, yielding where the first uncertainty is statistical, the second corresponds to the experimental systematic uncertainty, and the third to the physics-modelling systematic uncertainty.

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A search for weakly interacting massive dark-matter particles produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and missing transverse momentum are considered. The analysis uses of proton-proton collision data recorded by the ATLAS experiment at  TeV in 2015 and 2016.

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This paper presents a measurement of the polarisation of leptons produced in decays which is performed with a dataset of proton-proton collisions at TeV, corresponding to an integrated luminosity of 20.2 fb recorded with the ATLAS detector at the LHC in 2012. The decays are reconstructed from a hadronically decaying lepton with a single charged particle in the final state, accompanied by a lepton that decays leptonically.

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Measurements of longitudinal flow correlations are presented for charged particles in the pseudorapidity range using 7 and 470 of Pb+Pb collisions at and 5.02 TeV, respectively, recorded by the ATLAS detector at the LHC. It is found that the correlation between the harmonic flow coefficients measured in two separated intervals does not factorise into the product of single-particle coefficients, and this breaking of factorisation, or flow decorrelation, increases linearly with the separation between the intervals.

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A search for the direct production of charginos and neutralinos in final states with at least two hadronically decaying tau leptons is presented. The analysis uses a dataset of collisions corresponding to an integrated luminosity of 36.1 fb , recorded with the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of 13 TeV.

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The differential cross-section for the production of a boson in association with a top quark is measured for several particle-level observables. The measurements are performed using of collision data collected with the ATLAS detector at the LHC in 2015 and 2016. Differential cross-sections are measured in a fiducial phase space defined by the presence of two charged leptons and exactly one jet matched to a -hadron, and are normalised with the fiducial cross-section.

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A search for heavy resonances decaying into a pair of bosons leading to and final states, where stands for either an electron or a muon, is presented. The search uses proton-proton collision data at a centre-of-mass energy of 13  corresponding to an integrated luminosity of 36.1  collected with the ATLAS detector during 2015 and 2016 at the Large Hadron Collider.

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The results of a search for new heavy bosons decaying to an electron or muon and a neutrino using proton-proton collision data at a centre-of-mass energy of  TeV are presented. The dataset was collected in 2015 and 2016 by the ATLAS experiment at the Large Hadron Collider and corresponds to an integrated luminosity of 36.1  .

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Article Synopsis
  • The analysis involves searching for massive colored resonances that decay into two jets using data from the ATLAS experiment at the LHC, collected in 2015 and 2016.
  • No significant anomalies were found compared to background predictions, leading to the exclusion of certain mass ranges for the lightest supersymmetric particle, which is identified as the top squark.
  • Results indicate that top squarks with specified mass ranges are excluded at a 95% confidence level, and additional limits on colored octet resonances are also established.
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The elliptic flow of prompt and non-prompt was measured in the dimuon decay channel in Pb+Pb collisions at   with an integrated luminosity of with the ATLAS detector at the LHC. The prompt and non-prompt signals are separated using a two-dimensional simultaneous fit of the invariant mass and pseudo-proper decay time of the dimuon system from the decay. The measurement is performed in the kinematic range of dimuon transverse momentum and rapidity   , , and 0-60% collision centrality.

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The inclusive and fiducial production cross-sections are measured in the lepton+jets channel using of proton-proton collision data at a centre-of-mass energy of 8 TeV recorded with the ATLAS detector at the LHC. Major systematic uncertainties due to the modelling of the jet energy scale and -tagging efficiency are constrained by separating selected events into three disjoint regions. In order to reduce systematic uncertainties in the most important background, the process is modelled using + jets events in a data-driven approach.

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Previous studies have shown that weighted angular moments derived from jet constituents encode the colour connections between partons that seed the jets. This paper presents measurements of two such distributions, the jet-pull angle and jet-pull magnitude, both of which are derived from the jet-pull angular moment. The measurement is performed in events with one leptonically decaying  boson and one hadronically decaying  boson, using of collision data recorded by the ATLAS detector at delivered by the Large Hadron Collider.

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The performance of the missing transverse momentum ( ) reconstruction with the ATLAS detector is evaluated using data collected in proton-proton collisions at the LHC at a centre-of-mass energy of 13 TeV in 2015. To reconstruct , fully calibrated electrons, muons, photons, hadronically decaying , and jets reconstructed from calorimeter energy deposits and charged-particle tracks are used. These are combined with the soft hadronic activity measured by reconstructed charged-particle tracks not associated with the hard objects.

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Searches for non-resonant and resonant Higgs boson pair production are performed in the channel with the final state of using 36.1  of proton-proton collision data recorded at a centre-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. No significant deviation from the Standard Model prediction is observed.

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Measurements of the azimuthal anisotropy in lead-lead collisions at = 5.02 TeV are presented using a data sample corresponding to 0.49 integrated luminosity collected by the ATLAS experiment at the LHC in 2015.

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A search for the electroweak production of charginos, neutralinos and sleptons decaying into final states involving two or three electrons or muons is presented. The analysis is based on 36.1 fb of  TeV proton-proton collisions recorded by the ATLAS detector at the Large Hadron Collider.

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Several extensions of the standard model predict associated production of dark-matter particles with a Higgs boson. Such processes are searched for in final states with missing transverse momentum and a Higgs boson decaying to a bb[over ¯] pair with the ATLAS detector using 36.1  fb^{-1} of pp collisions at a center-of-mass energy of 13 TeV at the LHC.

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A search for heavy pseudoscalar (A) and scalar (H) Higgs bosons decaying into a top quark pair (tt[over ¯]) has been performed with 20.3  fb^{-1} of proton-proton collision data collected by the ATLAS experiment at the Large Hadron Collider at a center-of-mass energy sqrt[s]=8  TeV. Interference effects between the signal process and standard model tt[over ¯] production, which are expected to distort the signal shape from a single peak to a peak-dip structure, are taken into account.

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Multi-particle cumulants and corresponding Fourier harmonics are measured for azimuthal angle distributions of charged particles in [Formula: see text] collisions at [Formula: see text] = 5.02 and 13 TeV and in [Formula: see text] + Pb collisions at [Formula: see text] = 5.02 TeV, and compared to the results obtained for low-multiplicity [Formula: see text] collisions at [Formula: see text] = 2.

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