This Letter presents a search for quantum black-hole production using 20.3 fb-1 of data collected with the ATLAS detector in pp collisions at the LHC at √s = 8 TeV. The quantum black holes are assumed to decay into a final state characterized by a lepton (electron or muon) and a jet.
View Article and Find Full Text PDFA search is presented for dark matter pair production in association with a W or Z boson in pp collisions representing 20.3 fb(-1) of integrated luminosity at √s=8 TeV using data recorded with the ATLAS detector at the Large Hadron Collider. Events with a hadronic jet with the jet mass consistent with a W or Z boson, and with large missing transverse momentum are analyzed.
View Article and Find Full Text PDFThis Letter presents measurements of the polarization of the top quark in top-antitop quark pair events, using 4.7 fb(-1) of proton-proton collision data recorded with the ATLAS detector at the Large Hadron Collider at √s=7 TeV. Final states containing one or two isolated leptons (electrons or muons) and jets are considered.
View Article and Find Full Text PDFEur Phys J C Part Fields
September 2014
This paper presents a study of the performance of the muon reconstruction in the analysis of proton-proton collisions at [Formula: see text] TeV at the LHC, recorded by the ATLAS detector in 2010. This performance is described in terms of reconstruction and isolation efficiencies and momentum resolutions for different classes of reconstructed muons. The results are obtained from an analysis of [Formula: see text] meson and [Formula: see text] boson decays to dimuons, reconstructed from a data sample corresponding to an integrated luminosity of 40 pb[Formula: see text].
View Article and Find Full Text PDFA measurement is presented of the [Formula: see text] production cross section at [Formula: see text] = 7 TeV using [Formula: see text] collision data corresponding to an integrated luminosity of 383 [Formula: see text], collected with the ATLAS experiment at the LHC. Selection of [Formula: see text](1020) mesons is based on the identification of charged kaons by their energy loss in the pixel detector. The differential cross section is measured as a function of the transverse momentum, [Formula: see text], and rapidity, [Formula: see text], of the [Formula: see text](1020) meson in the fiducial region 500 [Formula: see text] 1200 MeV, [Formula: see text] 0.
View Article and Find Full Text PDFMeasurements 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.
View Article and Find Full Text PDFTwo-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.
View Article and Find Full Text PDFThe 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.
View Article and Find Full Text PDFResults 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.
View Article and Find Full Text PDFThis 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.
View Article and Find Full Text PDFEur Phys J C Part Fields
August 2013
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.
View Article and Find Full Text PDFA 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.
View Article and Find Full Text PDFEur Phys J C Part Fields
May 2013
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.
View Article and Find Full Text PDFEur Phys J C Part Fields
March 2013
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.
View Article and Find Full Text PDFEur Phys J C Part Fields
March 2013
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.
View Article and Find Full Text PDFEur Phys J C Part Fields
March 2013
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.
View Article and Find Full Text PDFEur Phys J C Part Fields
December 2013
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.
View Article and Find Full Text PDFA 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.
View Article and Find Full Text PDFA 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.
View Article and Find Full Text PDFEur Phys J C Part Fields
July 2012
Based on an analysis of 300 world information sources, 19 types of centrifugal blood pumps were ascertained. Five new designs suggested have an idea in common: combination of the inlet of the disk pump and of the outlet of the impeller pump. This allows uniting the merits of the above pumps and excluding their shortcomings.
View Article and Find Full Text PDFHearts of 52 pups were studied histochemically and electron-microscopically at various stages of total-body hypothermia. The dependence of the myocardiocyte metabolic alterations on the factors acting in the myocardium during different stages of hypothermia and during subsequent warming is shown. The vitality of the cooled heart is largely determined by retaining not only of its function, but by its anatomo-physiological links with the organism.
View Article and Find Full Text PDFThe totally artificial heart (TAH) is now in development in two trends. First, there is the development of a bridge system for temporary support of cardiac function. The TAH with the extracorporeal pneumatic driving system Sinus-IS is more efficient and safer.
View Article and Find Full Text PDFSuccess of total artificial heart (TAH) implantation as a temporary measure depends on three factors: proper patient selection, adequate surgical technique, and safe cardiac prostheses. From 1986 until March 1990, 237 patients with stagnant heart failure were examined. Sixty-one patients (27%) were put on a waiting list.
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