66,696 research outputs found

    The implications from CANGAROO-III observations of TeV blazar PKS 2155-304

    Get PDF
    We have observed the high-frequency-peaked BL Lacertae object PKS2155-304 in 2004, 2005 and 2006 with the CANGAROO-III imaging atmospheric Cherenkov telescope, and have detected a signal above 660 GeV at the 4.8/sigma level during the 2006 outburst period. Intranight flux variability on time scale of half an hour is observed. From this variability time scale, the size of the TeV gamma-ray emission region is restricted to 5x10^13\delta cm, and the super massive black hole mass is estimated to be less than 1.9x10^8\delta M_{Solar}, where \delta is the beaming factor. The differential energy spectrum is obtained, and an upper limit of the extragalactic infrared background light (EBL) flux is derived under some assumption. We also fit a synchrotron self Compton (SSC) model to the spectral energy distribution (SED) and derive the beaming factor and magnetic field strength.Comment: 4 pages, 5 figures, proceedings of the "4th Heidelberg International Symposium on High Energy Gamma-Ray Astronomy" July 7-11, 2008, Heidelberg, German

    Research options for controlling Zoonotic disease in India, 2010-2015

    Get PDF
    BACKGROUND: Zoonotic infections pose a significant public health challenge for low- and middle-income countries and have traditionally been a neglected area of research. The Roadmap to Combat Zoonoses in India (RCZI) initiative conducted an exercise to systematically identify and prioritize research options needed to control zoonoses in India. METHODS AND FINDINGS: Priority setting methods developed by the Child Health and Nutrition Research Initiative were adapted for the diversity of sectors, disciplines, diseases and populations relevant for zoonoses in India. A multidisciplinary group of experts identified priority zoonotic diseases and knowledge gaps and proposed research options to address key knowledge gaps within the next five years. Each option was scored using predefined criteria by another group of experts. The scores were weighted using relative ranks among the criteria based upon the feedback of a larger reference group. We categorized each research option by type of research, disease targeted, factorials, and level of collaboration required. We analysed the research options by tabulating them along these categories. Seventeen experts generated four universal research themes and 103 specific research options, the majority of which required a high to medium level of collaboration across sectors. Research options designated as pertaining to 'social, political and economic' factorials predominated and scored higher than options focussing on ecological, genetic and biological, or environmental factors. Research options related to 'health policy and systems' scored highest while those related to 'research for development of new interventions' scored the lowest. CONCLUSIONS: We methodically identified research themes and specific research options incorporating perspectives of a diverse group of stakeholders. These outputs reflect the diverse nature of challenges posed by zoonoses and should be acceptable across diseases, disciplines, and sectors. The identified research options capture the need for 'actionable research' for advancing the prevention and control of zoonoses in India

    Coupled channel approach to strangeness S = -2 baryon-bayron interactions in Lattice QCD

    Get PDF
    The baryon-baryon interactions with strangeness S = -2 with the flavor SU(3) breaking are calculated for the first time by using the HAL QCD method extended to coupled channel system in lattice QCD. The potential matrices are extracted from the Nambu-Bethe-Salpeter wave functions obtained by the 2+1 flavor gauge configurations of CP-PACS/JLQCD Collaborations with a physical volume of 1.93 fm cubed and with m_pi/m_K = 0.96, 0.90, 0.86. The spatial structure and the quark mass dependence of the potential matrix in the baryon basis and in the SU(3) basis are investigated.Comment: 17 pages, 15 figure

    Υ and Υ′ leptonic widths, abμ, and mb from full lattice QCD

    Get PDF
    We determine the decay rate to leptons of the ground-state ϒ meson and its first radial excitation in lattice QCD for the first time. We use radiatively improved nonrelativistic QCD for the b quarks and include u, d, s and c quarks in the sea with u=d masses down to their physical values. We find Γðϒ → eþe−Þ ¼ 1.19ð11Þ keV and Γðϒ0 → eþe−Þ ¼ 0.69ð9Þ keV, both in good agreement with experimental results. The decay constants we obtain are included in a summary plot of meson decay constants from lattice QCD given in the Conclusions. We also test time moments of the vector current-current correlator against values determined from the b-quark contribution to σðeþe− → hadronsÞ and calculate the b-quark piece of the hadronic vacuum polarization contribution to the anomalous magnetic moment of the muon, ab μ ¼ 0.271ð37Þ × 10−10. Finally we determine the b-quark mass, obtaining in the MS scheme, ¯ m¯ bðm¯ b; nf ¼ 5Þ ¼ 4.196ð23Þ GeV, the most accurate result from lattice QCD to date

    The asteroseismic ground-based observational counterpart of CoRoT

    Get PDF
    We present different aspects of the ground-based observational counterpart of the CoRoT satellite mission. We give an overview of the selected asteroseismic targets, the numerous instruments and observatories involved, and the first scientific results.Comment: 3 pages, 2 tables, 1 figure, to be published in the conference proceedings 'Stellar Pulsation: Challenges for Theory and Observation' (31 May - 5 June, Santa Fe, New Mexico, US), publishers: American Institute of Physic

    OGLE-2013-BLG-0578L: Microlensing Binary Composed of A Brown Dwarf And An M Dwarf

    Full text link
    Determining physical parameters of binary microlenses is hampered by the lack of information about the angular Einstein radius due to the difficulty of resolving caustic crossings. In this paper, we present the analysis of the binary microlensing event OGLE-2013-BLG-0578, for which the caustic exit was precisely predicted in advance from real-time analysis, enabling to densely resolve the caustic crossing and to measure the Einstein radius. From the mass measurement of the lens system based on the Einstein radius combined with the additional information about the lens parallax, we identify that the lens is a binary that is composed of a late-type M-dwarf primary and a substellar brown-dwarf companion. The event demonstrates the capability of current real-time microlensing modeling and the usefulness of microlensing in detecting and characterizing faint or dark objects in the Galaxy.Comment: 5 pages, 2 tables, 4 figures, submitted to Ap

    Gender differences in the implementation of cardiovascular prevention measures after an acute coronary event

    Get PDF
    Objective To compare gender-related lifestyle changes and risk factor management after hospitalisation for a coronary event or revascularisation intervention in Europe. Method The EUROASPIRE III survey was carried out in 22 European countries in 2006-2007. Consecutive patients having had a coronary event or revascularisation before the age of 80 were identified. A total of 8966 patients (25.3% women) were interviewed and underwent clinical and biochemical tests at least 6 months after hospital admission. Trends in cardiovascular risk management were assessed on the basis of the 1994-1995, 1999-2000 and 2006-2007 EUROASPIRE surveys. Results Female survey participants were generally older and had a lower educational level than male participants (p<0.0001). The prevalences of obesity (p<0.0001), high blood pressure (BP) (p=0.001), elevated low-density lipoprotein (LDL)-cholesterol (p<0.0001) and diabetes (p<0.0001) were significantly higher in women than in men, whereas current smoking (p<0.0001) was significantly more common in men. The use of antihypertensive and antidiabetic drugs (but not that of other drugs) was more common in women than in men. However, BP (p<0.0001), LDL-cholesterol (p<0.0001) and HbA1c (p<0.0001) targets were less often achieved in women than in men. Between 1994 and 2007, cholesterol control improved less in women than in men (interaction: p=0.009), whereas trends in BP control (p=0.32) and glycaemia (p=0.36) were similar for both genders. Conclusion The EUROASPIRE III results show that despite similarities in medication exposure, women are less likely than men to achieve BP, LDL-cholesterol and HbA1c targets after a coronary event. This gap did not appear to narrow between 1994 and 2007

    Time Averaged VHE Spectrum of Mrk 421 in 2005

    Full text link
    The blazar Mrk421 was observed independently, but contemporaneously, in 2005 at TeV energies by MAGIC, the Whipple 10m telescope, and by a single VERITAS telescope during the construction phase of operations. A comparison of the time averaged spectra, in what was a relatively quiescent state, demonstrates the level of agreement between instruments. In addition, the increased sensitivity of the new generation instruments, and ever decreasing energy thresholds, questions how best to compare new observational data with archival results.Comment: Submitted to Proceedings of "4th Heidelberg International Symposium on High Energy Gamma-Ray Astronomy 2008

    Leptonic decays of the eta meson with the WASA detector at CELSIUS

    Full text link
    Decay channels of the eta meson with at least one lepton pair in the final state are discussed. Preliminary results on electron-positron pair production from the pd->He eta reaction from the WASA experiment at CELSIUS are presented.Comment: 8 pages, 7 figures, prepared for Symposium on Meson Physics at COSY-11 and WASA-at-COSY, Cracow, 17-22 June 200
    corecore