Causes of death in Vanuatu

Background The population of the Pacific Melanesian country of Vanuatu was 234,000 at the 2009 census. Apart from subsistence activities, economic activity includes tourism and agriculture. Current completeness of vital registration is considered too low to be usable for national statistics; mortality and life expectancy (LE) are derived from indirect demographic estimates from censuses/surveys. Some cause of death (CoD) data are available to provide information on major causes of premature death. Methods Deaths 2001–2007 were coded for cause (ICDv10) for ages 0–59 years from: hospital separations (HS) (n = 636), hospital medical certificates (MC) of death (n = 1,169), and monthly reports from community health facilities (CHF) (n = 1,212). Ill-defined causes were 3 % for hospital deaths and 20 % from CHF. Proportional mortality was calculated by cause (excluding ill-defined) and age group (0–4, 5–14 years), and also by sex for 15–59 years. From total deaths by broad age group and sex from 1999 and 2009 census analyses, community deaths were estimated by deduction of hospital deaths MC. National proportional mortality by cause was estimated by a weighted average of MC and CHF deaths. Results National estimates indicate main causes of deaths <5 years were: perinatal disorders (45 %) and malaria, diarrhea, and pneumonia (27 %). For 15–59 years, main causes of male deaths were: circulatory disease 27 %, neoplasms 13 %, injury 13 %, liver disease 10 %, infection 10 %, diabetes 7 %, and chronic respiratory disease 7 %; and for females: neoplasms 29 %, circulatory disease 15 %, diabetes 10 %, infection 9 %, and maternal deaths 8 %. Infection included tuberculosis, malaria, and viral hepatitis. Liver disease (including hepatitis and cancer) accounted for 18 % of deaths in adult males and 9 % in females. Non-communicable disease (NCD), including circulatory disease, diabetes, neoplasm, and chronic respiratory disease, accounted for 52 % of premature deaths in adult males and 60 % in females. Injuries accounted for 13 % in adult males and 6 % in females. Maternal deaths translate into an annual maternal mortality ratio of 130/100,000 for the period. Conclusion Vanuatu manifests a double burden of disease with significant proportional mortality from perinatal disorders and infection/pneumonia <5 years and maternal mortality, coupled with significant proportional mortality in adults (15–59 years) from cardiovascular disease (CVD), neoplasms, and diabetes

Accuracy versus precision in boosted top tagging with the ATLAS detector

The identification of top quark decays where the top quark has a large momentum transverse to the beam axis, known as top tagging, is a crucial component in many measurements of Standard Model processes and searches for beyond the Standard Model physics at the Large Hadron Collider. Machine learning techniques have improved the performance of top tagging algorithms, but the size of the systematic uncertainties for all proposed algorithms has not been systematically studied. This paper presents the performance of several machine learning based top tagging algorithms on a dataset constructed from simulated proton-proton collision events measured with the ATLAS detector at √s = 13 TeV. The systematic uncertainties associated with these algorithms are estimated through an approximate procedure that is not meant to be used in a physics analysis, but is appropriate for the level of precision required for this study. The most performant algorithms are found to have the largest uncertainties, motivating the development of methods to reduce these uncertainties without compromising performance. To enable such efforts in the wider scientific community, the datasets used in this paper are made publicly available

Measurement of single top-quark production in association with a W boson in pp collisions at root s = 13 TeV with the ATLAS detector

The inclusive cross section for the production of a single top quark in association with a W boson is measured using 140 fb-1 of proton-proton collision data collected with the ATLAS detector at root s = 13 TeV. Events containing two charged leptons and at least one jet identified as originating from a b-quark are selected. A multivariate discriminant is constructed to separate the tW signal from the t⁢ tbar background. The cross section is extracted using a profile likelihood fit to the signal and control regions and it is measured to be sigma t W = 7⁢5 + 15 - 14 pb, in good agreement with the Standard Model prediction. The measured cross section is used to extract a value for the left-handed form factor at the Wtb vertex times the Cabibbo-Kobayashi-Maskawa matrix element mod(fLV Vtb) of 0.97 +- 0.10

Test of lepton flavour universality in W-boson decays into electrons and τ-leptons using pp collisions at s \sqrt{s} = 13 TeV with the ATLAS detector

A measurement of the ratio of the branching fractions, Rτ/e = B(W → τν)/B(W → eν), is performed using a sample of W bosons originating from top-quark decays to final states containing τ-leptons or electrons. This measurement uses pp collisions at s =13TeV, collected by the ATLAS experiment at the Large Hadron Collider during Run 2, corresponding to an integrated luminosity of 140fb−1. The W → τντ (with τ → eνeντ) and W →eνe decays are distinguished using the differences in the impact parameter distributions and transverse momentum spectra of the electrons. The measured ratio of branching fractions Rτ/e = 0.975±0.012(stat.)±0.020(syst.), is consistent with the Standard Model assumption of lepton flavour universality in W-boson decays

Search for the jet-induced diffusion wake in the quark-gluon plasma via measurements of jet-track correlations in photon-jet events in Pb+Pb collisions at sNN=5.02TeV with the ATLAS detector

This paper presents a measurement of jet-track correlations in photon-jet events, using 1.72 nb^(-1) of Pb+Pb data at root(sNN) = 5.02 TeV recorded with the ATLAS detector at the LHC. Events with energetic photon-jet pairs are selected, where the photon and jet are approximately back-to-back in azimuth. The angular correlation between jets and charged-particle tracks with transverse momentum (pT) in the range 0.5-2.0 GeV in the hemisphere opposite to the jet, | phi(jet,track)| &gt; pi/2, is measured as a function of their relative pseudorapidity difference, | eta(jet,track)|. In central Pb+Pb collisions, these correlations are predicted to be sensitive to the diffusion wake in the quark-gluon plasma resulting from the lost energy of high-pT partons traversing the plasma, with a characteristic modification as a function of | eta(jet,track)|. The correlations are examined with different selections on the jet-to-photon pT ratio to select events with different degrees of energy loss. No diffusion wake signal is observed within the current sensitivity and upper limits at 95% confidence level on the diffusion wake amplitude are reported

Configuration, Performance, and Commissioning of the ATLAS b-jet Triggers for the 2022 and 2023 LHC data-taking periods

In 2022 and 2023, the Large Hadron Collider produced approximately two billion hadronic interactions each second from bunches of protons that collide at a rate of 40 MHz. The ATLAS trigger system is used to reduce this rate to a few kHz for recording. Selections based on hadronic jets, their energy, and event topology reduce the rate to O(10) kHz while maintaining high efficiencies for important signatures resulting in b-quarks, but to reach the desired recording rate of hundreds of Hz, additional real-time selections based on the identification of jets containing b-hadrons (b-jets) are employed to achieve low thresholds on the jet transverse momentum at the High-Level Trigger. The configuration, commissioning, and performance of the real-time ATLAS b-jet identification algorithms for the early LHC Run 3 collision data are presented. These recent developments provide substantial gains in signal efficiency for critical signatures; for the Standard Model production of Higgs boson pairs, a 50% improvement in selection efficiency is observed in final states with four b-quarks or two b-quarks and two hadronically decaying tau-leptons

Search for vector-like leptons coupling to first- and second-generation Standard Model leptons in pp collisions at s \sqrt{s} = 13 TeV with the ATLAS detector

A search for pair production of vector-like leptons coupling to first- and secondgeneration Standard Model leptons is presented. The search is based on a dataset of proton-proton collisions at root s = 13 TeV recorded with the ATLAS detector during Run 2 of the Large Hadron Collider, corresponding to an integrated luminosity of 140fb-1. Events are categorised depending on the flavour and multiplicity of leptons (electrons or muons), as well as on the scores of a deep neural network targeting particular signal topologies according to the decay modes of the vector-like leptons. In each of the signal regions, the scalar sum of the transverse momentum of the leptons and the missing transverse momentum is analysed. The main background processes are estimated using dedicated control regions in a simultaneous fit with the signal regions to data. No significant excess above the Standard Model background expectation is observed and limits are set at 95% confidence level on the production cross-sections of vector-like electrons and muons as a function of the vector-like lepton mass, separately for SU(2) doublet and singlet scenarios. The resulting mass lower limits are 1220GeV (1270GeV) and 320GeV (400GeV) for vector-like electrons (muons) in the doublet and singlet scenarios, respectively