Eur Phys J C Part Fields
July 2017
This paper describes the implementation and performance of a particle flow algorithm applied to 20.2 fb[Formula: see text] of ATLAS data from 8 TeV proton-proton collisions in Run 1 of the LHC. The algorithm removes calorimeter energy deposits due to charged hadrons from consideration during jet reconstruction, instead using measurements of their momenta from the inner tracker.
View Article and Find Full Text PDFEur Phys J C Part Fields
May 2017
This paper presents the method and performance of primary vertex reconstruction in proton-proton collision data recorded by the ATLAS experiment during Run 1 of the LHC. The studies presented focus on data taken during 2012 at a centre-of-mass energy of [Formula: see text] TeV. The performance has been measured as a function of the number of interactions per bunch crossing over a wide range, from one to seventy.
View Article and Find Full Text PDFDuring 2015 the ATLAS experiment recorded [Formula: see text] of proton-proton collision data at a centre-of-mass energy of [Formula: see text]. The ATLAS trigger system is a crucial component of the experiment, responsible for selecting events of interest at a recording rate of approximately 1 kHz from up to 40 MHz of collisions. This paper presents a short overview of the changes to the trigger and data acquisition systems during the first long shutdown of the LHC and shows the performance of the trigger system and its components based on the 2015 proton-proton collision data.
View Article and Find Full Text PDFHere we propose the combination of the 4-alkoxythiazole donor motif with highly photostable tetraazaanthracenes as electron-acceptor units. The segregated frontier orbitals in these dyes afford optical band gaps of 1.4-1.
View Article and Find Full Text PDFIntroduction: Pyrrolizidine alkaloids (PAs) are secondary plant metabolites with considerable hepatoxic, tumorigenic and genotoxic potential. For separation, reversed phase chromatography is commonly used because of its excellent compatibility with detection by mass spectrometry. However, reversed phase chromatography has a low selectivity for PAs.
View Article and Find Full Text PDF2-Coumaranones are evolving as a new, efficient, versatile, and synthetically accessible platform for the next generation chemiluminescent probes. Despite the favorable quantum yields, the exact mechanism of their chemiluminescence remains elusive. Here, we analyze the details of the mechanism of the 2-coumaranone chemiluminescence using a combination of experimental and computational methods.
View Article and Find Full Text PDFResults of a search for physics beyond the Standard Model in events containing an energetic photon and large missing transverse momentum with the ATLAS detector at the Large Hadron Collider are reported. As the number of events observed in data, corresponding to an integrated luminosity of 36.1 fb[Formula: see text] of proton-proton collisions at a centre-of-mass energy of [Formula: see text], is in agreement with the Standard Model expectations, model-independent limits are set on the fiducial cross section for the production of events in this final state.
View Article and Find Full Text PDFEur Phys J C Part Fields
February 2017
Direct searches for lepton flavour violation in decays of the Higgs and bosons with the ATLAS detector at the LHC are presented. The following three decays are considered: [Formula: see text], [Formula: see text], and [Formula: see text]. The searches are based on the data sample of proton-proton collisions collected by the ATLAS detector corresponding to an integrated luminosity of 20.
View Article and Find Full Text PDFTwo searches for new phenomena in final states containing a same-flavour opposite-sign lepton (electron or muon) pair, jets, and large missing transverse momentum are presented. These searches make use of proton-proton collision data, collected during 2015 and 2016 at a centre-of-mass energy [Formula: see text] [Formula: see text] by the ATLAS detector at the large hadron collider, which correspond to an integrated luminosity of [Formula: see text]. Both searches target the pair production of supersymmetric particles, squarks or gluinos, which decay to final states containing a same-flavour opposite-sign lepton pair via one of two mechanisms: a leptonically decaying boson in the final state, leading to a peak in the dilepton invariant-mass distribution around the boson mass; and decays of neutralinos (e.
View Article and Find Full Text PDFObjectives: There is increasing evidence that inflammation and biomechanical loading can influence the effects of bisphosphonates (BP). The aim of this study was to investigate the influence of tensile strain application combined with IL-1ß and clodronate or zoledronate on human periodontal ligament fibroblasts (HPdLF) in vitro.
Materials And Methods: HPdLF were cultured with 10 nM IL-1ß and 5 μM clodronate or zoledronate for 48 h.
This article presents measurements of [Formula: see text] differential cross-sections in a fiducial phase-space region, using an integrated luminosity of 3.2 fb[Formula: see text] of proton-proton data at a centre-of-mass energy of [Formula: see text] TeV recorded by the ATLAS experiment at the LHC in 2015. Differential cross-sections are measured as a function of the transverse momentum and absolute rapidity of the top quark, and of the transverse momentum, absolute rapidity and invariant mass of the [Formula: see text] system.
View Article and Find Full Text PDFEur Phys J C Part Fields
March 2017
This paper describes the algorithms for the reconstruction and identification of electrons in the central region of the ATLAS detector at the Large Hadron Collider (LHC). These algorithms were used for all ATLAS results with electrons in the final state that are based on the 2012 collision data produced by the LHC at [Formula: see text] = 8 [Formula: see text]. The efficiency of these algorithms, together with the charge misidentification rate, is measured in data and evaluated in simulated samples using electrons from [Formula: see text], [Formula: see text] and [Formula: see text] decays.
View Article and Find Full Text PDFThe synthesis and characterization of three novel fluorubine derivatives is reported via three to four simple reaction steps with isolatable intermediates. The functional dyes are characterized by their strong absorption peaks in the visible region and their high fluorescence quantum yields. A significant and useful feature is that the properties can be tuned over a wide range by changing the pH.
View Article and Find Full Text PDFThis paper presents a measurement of the polarisation of bosons from [Formula: see text] decays, reconstructed in events with one high-[Formula: see text] lepton and at least four jets. Data from collisions at the LHC were collected at [Formula: see text] = 8 TeV and correspond to an integrated luminosity of 20.2 fb[Formula: see text].
View Article and Find Full Text PDFThe reconstruction and calibration algorithms used to calculate missing transverse momentum ([Formula: see text] ) with the ATLAS detector exploit energy deposits in the calorimeter and tracks reconstructed in the inner detector as well as the muon spectrometer. Various strategies are used to suppress effects arising from additional proton-proton interactions, called pileup, concurrent with the hard-scatter processes. Tracking information is used to distinguish contributions from the pileup interactions using their vertex separation along the beam axis.
View Article and Find Full Text PDFMeasurements of jet activity in top-quark pair events produced in proton-proton collisions are presented, using 3.2 fb[Formula: see text] of collision data at a centre-of-mass energy of 13 TeV collected by the ATLAS experiment at the Large Hadron Collider. Events are chosen by requiring an opposite-charge [Formula: see text] pair and two -tagged jets in the final state.
View Article and Find Full Text PDFOBJECTIVE To compare the rates of and reasons for presenteeism associated with influenza-like illness (ILI) among healthcare professionals (HCPs) caring for hospitalized inpatient transplant recipients and internal medicine patients. DESIGN We designed a 10-question anonymous survey in which ILI was defined as fever (>37.8°C) and cough and/or sore throat and ILI B was defined as fever (>37.
View Article and Find Full Text PDFMelanoma of the skin is a common cancer only in Europeans, whereas it arises in internal body surfaces (mucosal sites) and on the hands and feet (acral sites) in people throughout the world. Here we report analysis of whole-genome sequences from cutaneous, acral and mucosal subtypes of melanoma. The heavily mutated landscape of coding and non-coding mutations in cutaneous melanoma resolved novel signatures of mutagenesis attributable to ultraviolet radiation.
View Article and Find Full Text PDFPurpose: We investigated the impact of different cut-offs on the prevalence of 25-hydroxyvitamin D [25-(OH)D] deficiency.
Methods: We used baseline data of 4149 participants (45-75 years, 50% women) of the population-based Heinz Nixdorf Recall study. Serum 25-(OH)D was measured with the Roche Cobas assay.
This paper reports a search for triboson [Formula: see text] production in two decay channels ([Formula: see text] and [Formula: see text] with [Formula: see text]) in proton-proton collision data corresponding to an integrated luminosity of 20.3 [Formula: see text] at a centre-of-mass energy of 8 [Formula: see text] with the ATLAS detector at the Large Hadron Collider. Events with exactly three charged leptons, or two leptons with the same electric charge in association with two jets, are selected.
View Article and Find Full Text PDFThe production of two prompt [Formula: see text] mesons, each with transverse momenta [Formula: see text] GeV and rapidity [Formula: see text], is studied using a sample of proton-proton collisions at [Formula: see text] TeV, corresponding to an integrated luminosity of 11.4 fb[Formula: see text] collected in 2012 with the ATLAS detector at the LHC. The differential cross-section, assuming unpolarised [Formula: see text] production, is measured as a function of the transverse momentum of the lower-[Formula: see text] [Formula: see text] meson, di-[Formula: see text] [Formula: see text] and mass, the difference in rapidity between the two [Formula: see text] mesons, and the azimuthal angle between the two [Formula: see text] mesons.
View Article and Find Full Text PDFA measurement of the [Formula: see text] and [Formula: see text] production cross sections in final states with either two same-charge muons, or three or four leptons (electrons or muons) is presented. The analysis uses a data sample of proton-proton collisions at [Formula: see text] TeV recorded with the ATLAS detector at the Large Hadron Collider in 2015, corresponding to a total integrated luminosity of 3.2 fb[Formula: see text].
View Article and Find Full Text PDFA measurement of the calorimeter response to isolated charged hadrons in the ATLAS detector at the LHC is presented. This measurement is performed with 3.2 nb[Formula: see text] of proton-proton collision data at [Formula: see text] [Formula: see text] from 2010 and 0.
View Article and Find Full Text PDFEur Phys J C Part Fields
September 2017
The rejection of forward jets originating from additional proton-proton interactions (pile-up) is crucial for a variety of physics analyses at the LHC, including Standard Model measurements and searches for physics beyond the Standard Model. The identification of such jets is challenging due to the lack of track and vertex information in the pseudorapidity range . This paper presents a novel strategy for forward pile-up jet tagging that exploits jet shapes and topological jet correlations in pile-up interactions.
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