167 research outputs found

    A Measurement of the Cosmic Microwave Background Damping Tail from the 2500-square-degree SPT-SZ survey

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    We present a measurement of the cosmic microwave background (CMB) temperature power spectrum using data from the recently completed South Pole Telescope Sunyaev-Zel'dovich (SPT-SZ) survey. This measurement is made from observations of 2540 deg2^2 of sky with arcminute resolution at 150150\,GHz, and improves upon previous measurements using the SPT by tripling the sky area. We report CMB temperature anisotropy power over the multipole range 650<<3000650<\ell<3000. We fit the SPT bandpowers, combined with the seven-year Wilkinson Microwave Anisotropy Probe (WMAP7) data, with a six-parameter LCDM cosmological model and find that the two datasets are consistent and well fit by the model. Adding SPT measurements significantly improves LCDM parameter constraints; in particular, the constraint on θs\theta_s tightens by a factor of 2.7. The impact of gravitational lensing is detected at 8.1σ8.1\, \sigma, the most significant detection to date. This sensitivity of the SPT+WMAP7 data to lensing by large-scale structure at low redshifts allows us to constrain the mean curvature of the observable universe with CMB data alone to be Ωk=0.0030.018+0.014\Omega_k=-0.003^{+0.014}_{-0.018}. Using the SPT+WMAP7 data, we measure the spectral index of scalar fluctuations to be ns=0.9623±0.0097n_s=0.9623 \pm 0.0097 in the LCDM model, a 3.9σ3.9\,\sigma preference for a scale-dependent spectrum with ns<1n_s<1. The SPT measurement of the CMB damping tail helps break the degeneracy that exists between the tensor-to-scalar ratio rr and nsn_s in large-scale CMB measurements, leading to an upper limit of r<0.18r<0.18 (95%,C.L.) in the LCDM+rr model. Adding low-redshift measurements of the Hubble constant (H0H_0) and the baryon acoustic oscillation (BAO) feature to the SPT+WMAP7 data leads to further improvements. The combination of SPT+WMAP7+H0H_0+BAO constrains ns=0.9538±0.0081n_s=0.9538 \pm 0.0081 in the LCDM model, a 5.7σ5.7\,\sigma detection of ns<1n_s < 1, ... [abridged]Comment: 21 pages, 10 figures. Replaced with version accepted by ApJ. Data products are available at http://pole.uchicago.edu/public/data/story12

    A Comparison of Maps and Power Spectra Determined from South Pole Telescope and Planck Data

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    We study the consistency of 150 GHz data from the South Pole Telescope (SPT) and 143 GHz data from the Planck satellite over the patch of sky covered by the SPT-SZ survey. We first visually compare the maps and find that the residuals appear consistent with noise after accounting for differences in angular resolution and filtering. We then calculate (1) the cross-spectrum between two independent halves of SPT data, (2) the cross-spectrum between two independent halves of Planck data, and (3) the cross-spectrum between SPT and Planck data. We find the three cross-spectra are well-fit (PTE = 0.30) by the null hypothesis in which both experiments have measured the same sky map up to a single free calibration parameter---i.e., we find no evidence for systematic errors in either data set. As a by-product, we improve the precision of the SPT calibration by nearly an order of magnitude, from 2.6% to 0.3% in power. Finally, we compare all three cross-spectra to the full-sky Planck power spectrum and find marginal evidence for differences between the power spectra from the SPT-SZ footprint and the full sky. We model these differences as a power law in spherical harmonic multipole number. The best-fit value of this tilt is consistent among the three cross-spectra in the SPT-SZ footprint, implying that the source of this tilt is a sample variance fluctuation in the SPT-SZ region relative to the full sky. The consistency of cosmological parameters derived from these datasets is discussed in a companion paper.Comment: 15 pages, 9 figures. Published in The Astrophysical Journal. Current arxiv version matches published versio

    First Results for the Beam Commissioning of the CERN Multi-Turn Extraction

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    The Multi-Turn Extraction (MTE), a new type of extraction based on beam trapping inside stable islands in horizontal phase space, has been commissioned during the 2008 run of the CERN Proton Synchrotron. Both singleand multi-bunch beams with a total intensity up to 1.4 1013 protons have been extracted with efficiencies up to 98%. Furthermore, injection tests in the CERN Super Proton Synchrotron were performed, with the beam then accelerated and extracted to produce neutrinos for the CERN Neutrino-to-Gran Sasso experiments. The results of the extensive measurement campaign are presented and discussed in detail

    Energy Linearity and Resolution of the ATLAS Electromagnetic Barrel Calorimeter in an Electron Test-Beam

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    A module of the ATLAS electromagnetic barrel liquid argon calorimeter was exposed to the CERN electron test-beam at the H8 beam line upgraded for precision momentum measurement. The available energies of the electron beam ranged from 10 to 245 GeV. The electron beam impinged at one point corresponding to a pseudo-rapidity of eta=0.687 and an azimuthal angle of phi=0.28 in the ATLAS coordinate system. A detailed study of several effects biasing the electron energy measurement allowed an energy reconstruction procedure to be developed that ensures a good linearity and a good resolution. Use is made of detailed Monte Carlo simulations based on Geant which describe the longitudinal and transverse shower profiles as well as the energy distributions. For electron energies between 15 GeV and 180 GeV the deviation of the measured incident electron energy over the beam energy is within 0.1%. The systematic uncertainty of the measurement is about 0.1% at low energies and negligible at high energies. The energy resolution is found to be about 10% sqrt(E) for the sampling term and about 0.2% for the local constant term

    High morbid-mortability and reduced level of osteoporosis diagnosis among elderly people who had hip fractures in São Paulo City

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    OBJECTIVE: To know the morbid-mortality following an osteoporotic hip fracture in elderly patients living in São Paulo. PATIENTS AND METHODS: This study evaluated prospectively all patient over 60 years admitted in 2 school-hospitals in the city of São Paulo in a following 6-month period due to a osteoporotic proximal femur fracture. All of them filled up the Health Assessment Questionnaire (HAQ) and had their chart reviewed. After 6 months they were re-interviewed. Linear regression analysis was utilized to determine the factors related to functional ability. RESULTS: 56 patients were included (mean age 80.7 ± 7.9 years old, 80.4% females). After the 6-month follow up the mortality rate was 23.2%. Only 30% of the patients returned to their previous activities, and 11.6% became totally dependent. Factors related to worse functional ability after fracture were HAQ before fracture, institutionalization after fracture and age (r² 0.482). The diagnosis of osteoporosis was informed only by 13.9% of them, and just 11.6% received any treatment for that. CONCLUSION: Our results showed the great impact of these fractures on mortality and in the functional ability of these patients. Nevertheless, many of our physicians do not inform the patients about the diagnosis of osteoporosis and, consequently, the treatment of this condition is jeopardized.As fraturas osteoporóticas de fêmur proximal trazem graves conseqüências quanto à morbimortalidade e à qualidade de vida, mas desconhece-se este impacto no Brasil. OBJETIVO: Conhecer a morbimortalidade decorrente deste tipo de fraturas em idosos na cidade de São Paulo. MÉTODOS: Foram incluídos todos os pacientes com mais de 60 anos internados por fraturas de fêmur proximal durante seis meses, em dois hospitais de São Paulo. Os pacientes preencheram o questionário de capacidade funcional (HAQ), tiveram seu prontuário examinado e foram reavaliados após seis meses. Utilizou-se a análise de regressão linear para determinar os fatores relacionados à capacidade funcional. RESULTADOS: Cinqüenta e seis pacientes foram incluídos no estudo (80,7 ± 7,9 anos; 80,4% mulheres). A mortalidade em seis meses foi de 23,2%. Apenas 30% retornaram plenamente às suas atividades prévias e 11,6% tornaram-se completamente dependentes. Os fatores que mais bem conseguiram prever pior capacidade funcional após a fratura foram HAQ pré-fratura, institucionalização pós-fratura e idade (r² 0,482). Somente 13,9% receberam o diagnóstico de osteoporose e 11,6% iniciaram algum tratamento. CONCLUSÕES: Os resultados do presente estudo demonstram o impacto deste tipo de fraturas sobre a mortalidade e a capacidade funcional. Entretanto, a falha médica no diagnóstico e na orientação de tratamento da osteoporose permanece elevada.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaSanta Casa de Misericórdia de São Paulo Departamento de OrtopediaUNIFESP-EPM EPMUNIFESP, EPM, EPMSciEL

    The LHC Injection Tests

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    A series of LHC injection tests was performed in August and September 2008. The first saw beam injected into sector 23; the second into sectors 78 and 23; the third into sectors 78-67 and sectors 23-34-45. The fourth, into sectors 23-34-45, was performed the evening before the extended injection test on the 10th September which saw both beams brought around the full circumference of the LHC. The tests enabled the testing and debugging of a number of critical control and hardware systems; testing and validation of instrumentation with beam for the first time; deployment, and validation of a number of measurement procedures. Beam based measurements revealed a number of machine configuration issues that were rapidly resolved. The tests were undoubtedly an essential precursor to the successful start of LHC beam commissioning. This paper provides an outline of preparation for the tests, the machine configuration and summarizes the measurements made and individual system performance
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