2,704 research outputs found

    On the high energy proton spectrum measurements

    Get PDF
    The steepening of the proton spectrum beyond 1000 GeV and the rise in inelastic cross sections between 20 and 600 GeV observed by the PROTON-1-2-3 satellite experiments were explained by systematic effects of energy dependent albedo (backscatter) from the calorimeter

    Study of muons near shower cores at sea level using the E594 neutrino detector

    Get PDF
    The E594 neutrino detector has been used to study the lateral distribution of muons of energy 3 GeV near shower cores. The detector consists of a 340 ton fine grain calorimeter with 400,000 cells of flash chamber and dimensions of 3.7 m x 20 m x 3.7 m (height). The average density in the calorimeter is 1.4 gm/sq cm, and the average Z is 21. The detector was triggered by four 0.6 sq m scintillators placed immediately on the top of the calorimeter. The trigger required at least two of these four counters. The accompanying extensive air showers (EAS) was sampled by 14 scintillation counters located up to 15 m from the calorimeter. Several off line cuts have been applied to the data. Demanding five particles in at least two of the trigger detectors, a total of 20 particles in all of them together, and an arrival angle for the shower 450 deg reduced the data sample to 11053 events. Of these in 4869 cases, a computer algorithm found at least three muons in the calorimeter

    The composition of cosmic rays near the Bend (10 to the 15th power eV) from a study of muons in air showers at sea level

    Get PDF
    The distribution of muons near shower cores was studied at sea level at Fermilab using the E594 neutrino detector to sample the muon with E testing 3 GeV. These data are compared with detailed Monte Carlo simulations to derive conclusions about the composition of cosmic rays near the bend in the all particle spectrum. Monte Carlo simulations generating extensive air showers (EAS) with primary energy in excess of 50 TeV are described. Each shower record contains details of the electron lateral distribution and the muon and hadron lateral distributions as a function of energy, at the observation level of 100g/cm. The number of detected electrons and muons in each case was determined by a Poisson fluctuation of the number incident. The resultant predicted distribution of muons, electrons, the rate events are compared to those observed. Preliminary results on the rate favor a heavy primary dominated cosmic ray spectrum in energy range 50 to 1000 TeV

    Remote sensing data from CLARET: A prototype CART data set

    Get PDF
    The data set containing radiation, meteorological , and cloud sensor observations is documented. It was prepared for use by the Department of Energy's Atmospheric Radiation Measurement (ARM) Program and other interested scientists. These data are a precursor of the types of data that ARM Cloud And Radiation Testbed (CART) sites will provide. The data are from the Cloud Lidar And Radar Exploratory Test (CLARET) conducted by the Wave Propagation Laboratory during autumn 1989 in the Denver-Boulder area of Colorado primarily for the purpose of developing new cloud-sensing techniques on cirrus. After becoming aware of the experiment, ARM scientists requested archival of subsets of the data to assist in the developing ARM program. Five CLARET cases were selected: two with cirrus, one with stratus, one with mixed-phase clouds, and one with clear skies. Satellite data from the stratus case and one cirrus case were analyzed for statistics on cloud cover and top height. The main body of the selected data are available on diskette from the Wave Propagation Laboratory or Los Alamos National Laboratory

    Composition of primary cosmic rays near the bend from a study of hadrons in air showers at sea level

    Get PDF
    Data on hadrons in air showers arriving at sea level were studied to find sensitivity to primary cosmic ray composition. The rate of showers which satisfy minimum shower density and hadron energy requirements as well as the rate of showers containing hadrons delayed with respect to the electron shower front are compared to Monte Carlo simulations. The data on the rate of total triggers and delayed hadrons are compared to predicted rates for two models of primary composition. The data are consistent with models which require an increasing heavy nuclei fraction near 10 to the 15th power eV. The spectra which are consistent with the observed rate are also compared to the observed shower size spectrum at sea level and mountain level

    An early Harvard 'Memorandum' on anti-depression policies

    Full text link
    [Introductory Note by David Laidler (University of Western Ontario) and Roger Sandilands (University of Strathclyde) ...] The Memorandum which this note introduces was completed by three young members of the Harvard economics department sometime in January 1932 Two of them, Lauchlin Currie and Harry Dexter White were soon to play key roles on the American, indeed the world-wide, policy scene. Both of them would go to Washington in 1934 as founding members of Jacob Viner’s 'Freshman Brains Trust'. In due course, first at the Federal Reserve Board, and later at the Treasury and the White House, Currie would become a highly visible and leading advocate of expansionary fiscal policy, while White, at the Treasury, was to be a co-architect, with Keynes, of the Bretton Woods system. Both would fall victim to anti-communist witch-hunts in the late 1940s, in White’s case perhaps at the cost of his life, since he died of a heart attack in 1948 three days after a strenuous hearing before the House Committee on Unamerican Activities (HUAC). The third author, P. T. Ellsworth, later a Professor of Economics at the University of Wisconsin, is perhaps best remembered nowadays as the author of a leading textbook in International Economics, though it is worth noting that he was also a very early (late 1936) but hitherto unrecognised discoverer of what came to be called the IS-LM model as a means of elucidating issues raised by Keynes' 'General Theory'. It is not known how widely this Memorandum was circulated, but the fact that it is a piece of policy advocacy, combined with its relatively polished style, makes it inconceivable that it was meant for the eyes and files of its authors alone. As readers will see, it sketches out an explanation of the then rapidly developing Great Contraction, as well as a comprehensive and radical policy programme for dealing with it. In keeping with its authors’ explanation of the Contraction as a consequence of a collapsing money supply, the main domestic components of that programme were to be vigorously expansionary open-market operations and substantial deficit spending that, particularly in its early stages, was to be financed by money creation; its international dimension involved a return to free trade and serious efforts to resolve the problems of international indebtedness that had originated in the Great War and in the Treaty of Versailles which had brought it to an uneasy end in 1919. [...

    The Study of TeV Variability and Duty Cycle of Mrk 421 from 3 Years of Observations with the Milagro Observatory

    Full text link
    TeV flaring activity with time scales as short as tens of minutes and an orphan TeV flare have been observed from the blazar Markarian 421 (Mrk 421). The TeV emission from Mrk 421 is believed to be produced by leptonic synchrotron self-Compton (SSC) emission. In this scenario, correlations between the X-ray and the TeV fluxes are expected, TeV orphan flares are hardly explained and the activity (measured as duty cycle) of the source at TeV energies is expected to be equal or less than that observed in X-rays if only SSC is considered. To estimate the TeV duty cycle of Mrk 421 and to establish limits on its variability at different time scales, we continuously observed Mrk 421 with the Milagro observatory. Mrk 421 was detected by Milagro with a statistical significance of 7.1 standard deviations between 2005 September 21 and 2008 March 15. The observed spectrum is consistent with previous observations by VERITAS. We estimate the duty cycle of Mrk 421 for energies above 1 TeV for different hypothesis of the baseline flux and for different flare selections and we compare our results with the X-ray duty cycle estimated by Resconi et al. 2009. The robustness of the results is discussed.Comment: 27 pages, 6 figures, ApJ accepte

    Aerodynamic Flight-Test Results for the Adaptive Compliant Trailing Edge

    Get PDF
    The aerodynamic effects of compliant flaps installed onto a modified Gulfstream III airplane were investigated. Analyses were performed prior to flight to predict the aerodynamic effects of the flap installation. Flight tests were conducted to gather both structural and aerodynamic data. The airplane was instrumented to collect vehicle aerodynamic data and wing pressure data. A leading-edge stagnation detection system was also installed. The data from these flights were analyzed and compared with predictions. The predictive tools compared well with flight data for small flap deflections, but differences between predictions and flight estimates were greater at larger deflections. This paper describes the methods used to examine the aerodynamics data from the flight tests and provides a discussion of the flight-test results in the areas of vehicle aerodynamics, wing sectional pressure coefficient profiles, and air data
    corecore