15,027,132 research outputs found

    Analysis of Dilepton Invariant Mass Spectrum in C+C at 2 and 1 AGeV

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    Recently the HADES collaboration has published the invariant mass spectrum of e+ee^+e^- pairs, dN/dMe+e_{e^+e^-}, produced in C+C collisions at 2 AGeV. Using electromagnetic probes, one hopes to get in this experiment information on hadron properties at high density and temperature. Simulations show that firm conclusions on possible in-medium modifications of meson properties will only be possible when the elementary meson production cross sections, especially in the pn channel, as well as production cross sections of baryonic resonances are better known. Presently one can conclude that a) simulations overpredict by far the cross section at Me+eMω0M_{e^+e^-} \approx M_{\omega}{^0} if free production cross sections are used and that b) the upper limit of the η\eta decay into e+ee^+e^- is smaller than the present upper limit of the Particle Data Group. This is the result of simulations using the Isospin Quantum Molecular Dynamics (IQMD) approach.Comment: 28 pages, 15 figures, 3 tables, ps file recommende

    Antiproton-proton partial-wave analysis below 925 MeV/c

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    A partial-wave analysis of all antiproton-proton scattering data below 925 MeV/c antiproton laboratory momentum is presented. The method used is adapted from the Nijmegen phase-shift analyses of pp and np scattering data. The Nijmegen 1993 antiproton-proton database, consisting of 3646 antiproton-proton scattering data, is presented and discussed. The best fit to this database results in chi^2_min/Ndata = 1.043. The pseudovector coupling constant of the charged pion to nucleons is determined to be (f_c)^2 = 0.0732(11) at the pion pole, where the error is statistical.Comment: Report THEF-NYM 93.02 42 pages REVTeX, 7 separate postscript figures appended. Accepted for publication in Phys. Rev.

    Sound Static Deadlock Analysis for C/Pthreads (Extended Version)

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    We present a static deadlock analysis approach for C/pthreads. The design of our method has been guided by the requirement to analyse real-world code. Our approach is sound (i.e., misses no deadlocks) for programs that have defined behaviour according to the C standard, and precise enough to prove deadlock-freedom for a large number of programs. The method consists of a pipeline of several analyses that build on a new context- and thread-sensitive abstract interpretation framework. We further present a lightweight dependency analysis to identify statements relevant to deadlock analysis and thus speed up the overall analysis. In our experimental evaluation, we succeeded to prove deadlock-freedom for 262 programs from the Debian GNU/Linux distribution with in total 2.6 MLOC in less than 11 hours

    An Analysis of the 12^{12}C+12^{12}C Reaction Using a New Type of Coupling Potential

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    A new approach has been used to explain the experimental data for the 12^{12}C+12^{12}C system over a wide energy range in the laboratory system from 32.0 MeV to 126.7 MeV. This new coupled-channels based approach involves replacing the usual first derivative coupling potential by a new, second-derivative coupling potential. This paper first shows and discusses the limitation of the standard coupled-channels theory in the case where one of the nuclei in the reaction is strongly deformed. Then, this new approach is shown to improve consistently the agreement with the experimental data: the elastic scattering, single-2+^{+} and mutual-2+^{+} excitation inelastic scattering data as well as their 90^{\circ} elastic and inelastic excitation functions with little energy-dependent potentials. This new approach makes major improvement on all the previous coupled-channels calculations for this system.Comment: 24 pages with 9 figure

    Market Analysis of Plant-based Drugs C. The Cannabis Market

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    An estimated quarter of a billion people, or around 5 per cent of the global adult population, used drugs at least once in 2015. Even more worrisome is the fact that about 29.5 million of those drug users, or 0.6 per cent of the global adult population, suffer from drug use disorders. This means that their drug use is harmful to the point that they may experience drug dependence and require treatment.The magnitude of the harm caused by drug use is underlined by the estimated 28 million years of "healthy" life (disability-adjusted life years (DALYs)) lost worldwide in 2015 as a result of premature death and disability caused by drug use.Of those years lost, 17 million were attributable solely to drug use disorders across all drug types. DALYs attributable to morbidity and mortality resulting from all causes of drug use have increased overall in the past decade.Yet, with fewer than one in six persons with drug use disorders provided with treatment each year, the availability of and access to science-based services for the treatment of drug use disorders and related conditions remain limited

    Impact Analysis of Oil Pollution using Change Detection Techniques in Kuwait

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    The present study reveals impact of oil pollution in the environment of Kuwait. The change detection techniques were applied to analyze the changes. The present study has been analyzed using digital satellite data such as 1990, 1993, 1999 and 2006. Based on hierarchy the data were applied various image processing technique like, principal component analysis, change detection analysis between 1993 to 1999 and 1999 to 2006, filtering techniques, classification, accuracy assessment and post classification methods. The results are revealed that the majority (90%) of the oil pollution occurred in the southern part of Kuwait

    Task A, Analysis of C-W Data, Final Report

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    The object of this investigation is to obtain additional information concerning the effects of aurora on high frequency radio signals which is essential to a complete understanding of new modes of propagation that have tactical and strategic applications.Signal Corps Contract No. DA-36-039-SC-71137 Department of the Army Project No. 3-99-03-022 Signal Corps Project No. 182BLIST OF FIGURES -- [SECTION I] PURPOSE -- [SECTION II] ABSTRACT -- [SECTION III] PUBLICATIONS. LECTURES, REPORTS AND CONFERENCES -- [SECTION IV] FACTUAL DATA : 1. Signal Outage Time on Short Paths and Blackouts Compared for Years of High and Low Solar Activity. ; 2. Study of Possible Relations between Transmission over Long Paths and Ionospheric,Magnetic and Solar Phenomena. ; 3. Study of Fluctuation Indices. ; 4. Effects of Ionospheric Absorption and Irregularities on 4 Mc/s Short Path Transmission. ; 5. F2 Region Parameters at College for the Period June 1941 Through December 1956. ; 6. Tables of Monthly Medians Signal Strength June 1949-December 1950 and January 1954-October 1955. -- [SECTION V] OVERALL CONCLUSIONS -- [SECTION VI] RECOMMENDATIONS -- [SECTION VII] PERSONNELYe

    Polarized Parton Distribution in Neutrino Induced Heavy Flavor Production

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    In order to examine polarized strange quark distribution, semi-inclusive D/\Dbar production in neutrino deep inelastic scattering is studied including O(αs){\cal O}(\alpha_s) corrections. Cross section and spin asymmetry are calculated by using various parametrizations of polarized parton distribution functions. It is found that \Dbar production is promising to directly extract the polarized strange sea.Comment: 3 pages, 2 figures. Talk given at the NuFact02 workshop, London, UK, July 1-6, 200
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