Publications by authors named "Staszewski R"

This paper presents the performance of the ATLAS muon reconstruction during the LHC run with [Formula: see text] collisions at [Formula: see text]-8 TeV in 2011-2012, focusing mainly on data collected in 2012. Measurements of the reconstruction efficiency and of the momentum scale and resolution, based on large reference samples of [Formula: see text], [Formula: see text] and [Formula: see text] decays, are presented and compared to Monte Carlo simulations. Corrections to the simulation, to be used in physics analysis, are provided.

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Additional jet activity in dijet events is measured using [Formula: see text] collisions at ATLAS at a centre-of-mass energy of [Formula: see text], for jets reconstructed using the [Formula: see text] algorithm with radius parameter [Formula: see text]. This is done using variables such as the fraction of dijet events without an additional jet in the rapidity interval bounded by the dijet subsystem and correlations between the azimuthal angles of the dijet s. They are presented, both with and without a veto on additional jet activity in the rapidity interval, as a function of the scalar average of the transverse momenta of the dijet s and of the rapidity interval size.

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The inclusive top quark pair ([Formula: see text]) production cross-section [Formula: see text] has been measured in proton-proton collisions at [Formula: see text] and [Formula: see text] with the ATLAS experiment at the LHC, using [Formula: see text] events with an opposite-charge [Formula: see text] pair in the final state. The measurement was performed with the 2011 7 TeV dataset corresponding to an integrated luminosity of 4.6 [Formula: see text] and the 2012 8 TeV dataset of 20.

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Measurements of the variation of inclusive jet suppression as a function of relative azimuthal angle, Δφ, with respect to the elliptic event plane provide insight into the path-length dependence of jet quenching. ATLAS has measured the Δφ dependence of jet yields in 0.14 nb(-1) of √(s(NN))=2.

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Two-particle correlations in relative azimuthal angle (Δø) and pseudorapidity (Δη) are measured in sqrt[s(NN)] = 5.02 TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1 μb(-1) of data as a function of transverse momentum (p(T)) and the transverse energy (ΣE(T)(Pb)) summed over 3.

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The ATLAS experiment has observed 1995 Z boson candidates in data corresponding to 0.15  nb(-1) of integrated luminosity obtained in the 2011 LHC Pb+Pb run at sqrt[s(NN)]=2.76  TeV.

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Results of a search for new phenomena in events with an energetic photon and large missing transverse momentum in proton-proton collisions at sqrt[s] = 7 TeV are reported. Data collected by the ATLAS experiment at the LHC corresponding to an integrated luminosity of 4.6 fb(-1) are used.

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This Letter presents a search for magnetic monopoles with the ATLAS detector at the CERN Large Hadron Collider using an integrated luminosity of 2.0  fb(-1) of pp collisions recorded at a center-of-mass energy of sqrt[s]=7  TeV. No event is found in the signal region, leading to an upper limit on the production cross section at 95% confidence level of 1.

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Article Synopsis
  • The inclusive jet cross-section has been measured in proton-proton collisions at a specified energy level using data from the ATLAS detector at the Large Hadron Collider, with focus on a 2011 dataset.
  • Jets were identified using a specific algorithm with two different radius settings, and the double-differential cross-section is analyzed based on jet momentum and rapidity within defined ranges.
  • The study compares findings against QCD predictions and includes analyses that can refine our understanding of parton distribution functions by addressing systematic uncertainties and correlations between measurements.
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The luminosity calibration for the ATLAS detector at the LHC during collisions at [Formula: see text] in 2010 and 2011 is presented. Evaluation of the luminosity scale is performed using several luminosity-sensitive detectors, and comparisons are made of the long-term stability and accuracy of this calibration applied to the collisions at [Formula: see text]. A luminosity uncertainty of [Formula: see text] is obtained for the 47 pb of data delivered to ATLAS in 2010, and an uncertainty of [Formula: see text] is obtained for the 5.

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A search for a charged Higgs boson () in [Formula: see text] decays is presented, where one of the top quarks decays via →, followed by → two jets ([Formula: see text]). The other top quark decays to , where the  boson then decays into a lepton (/) and a neutrino. The data were recorded in collisions at [Formula: see text] by the ATLAS detector at the LHC in 2011, and correspond to an integrated luminosity of 4.

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A measurement of splitting scales, as defined by the clustering algorithm, is presented for final states containing a boson produced in proton-proton collisions at a centre-of-mass energy of 7 TeV. The measurement is based on the full 2010 data sample corresponding to an integrated luminosity of 36 pb which was collected using the ATLAS detector at the CERN Large Hadron Collider. Cluster splitting scales are measured in events containing bosons decaying to electrons or muons.

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A search for supersymmetric particles in final states with zero, one, and two leptons, with and without jets identified as originating from -quarks, in 4.7 fb of [Formula: see text] collisions produced by the Large Hadron Collider and recorded by the ATLAS detector is presented. The search uses a set of variables carrying information on the event kinematics transverse and parallel to the beam line that are sensitive to several topologies expected in supersymmetry.

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A measurement of the top quark pair production cross section in the final state with a hadronically decaying tau lepton and jets is presented. The analysis is based on proton-proton collision data recorded by the ATLAS experiment at the LHC, with a centre-of-mass energy of 7 TeV. The data sample corresponds to an integrated luminosity of 1.

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The measurement of the jet energy resolution is presented using data recorded with the ATLAS detector in proton-proton collisions at [Formula: see text]. The sample corresponds to an integrated luminosity of 35 pb. Jets are reconstructed from energy deposits measured by the calorimeters and calibrated using different jet calibration schemes.

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A measurement of jet shapes in top-quark pair events using 1.8 fb of [Formula: see text] collision data recorded by the ATLAS detector at the LHC is presented. Samples of top-quark pair events are selected in both the single-lepton and dilepton final states.

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A search is presented for direct top squark pair production in final states with one isolated electron or muon, jets, and missing transverse momentum in proton-proton collisions at sqrt[s] = 7 TeV. The measurement is based on 4.7 fb(-1) of data collected with the ATLAS detector at the LHC.

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A search for direct pair production of supersymmetric top squarks (t(1)) is presented, assuming the t(1) decays into a top quark and the lightest supersymmetric particle, χ(1)(0), and that both top quarks decay to purely hadronic final states. A total of 16 (4) events are observed compared to a predicted standard model background of 13.5(-3.

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Article Synopsis
  • * The study used a data sample with an integrated luminosity of 2.05 fb at a proton-proton collision energy of 7 TeV, but found no evidence of resonance.
  • * Limits on the production of narrow bosons were established, with 95% credibility level limits showing excluded mass ranges from 500 GeV to 1300 GeV, specifically ruling out a leptophobic topcolor boson below 880 GeV.
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The purpose of the work was to analyze the smoking behaviors of the medical staff in hospitals. A typical group of employees in one of the biggest hospitals in Poland was examined thoroughly. The medical examination was carried out by means of standardized investigative instruments--questionnaires processed by the European Network for Smoke-free Hospital.

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Cutaneous collagenous vasculopathy (CCV) is an idiopathic microangiopathy involving the superficial blood vessels that was initially reported in a 54-year-old male. We recently have identified this rarely reported entity in three Caucasian males. The first patient was a 59-year-old male with diabetes, hypertension and hypercholesterolemia who presented with multiple, red, blanchable, asymptomatic telangiectasias covering the extensor surface of the forearms, the lower abdomen and parts of the chest.

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Methamphetamine (METH) is a widely abused psychostimulant. Multiple high doses of METH cause long-term toxicity to dopamine (DA) and serotonin (5-HT) nerve terminals in the brain, as evidenced by decreases in DA and 5-HT content, decreases in tyrosine and tryptophan hydroxylase activities, decreases in DA and 5-HT re-uptake sites, and nerve terminal degeneration. Multiple high doses of METH are known to elicit a rapid increase in DA release and hyperthermia.

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Ultraviolet radiation (UVR) exposure induces profound changes in the synthesis and secretion of various cytokines both in vivo and in vitro. Little is known regarding the mechanism of these responses. This investigation evaluated the effects of UVR on the ability of a murine keratinocyte line (PAM 212) to produce interleukin 3 (IL-3) and granulocyte-macrophage colony stimulating factor (GM-CSF).

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