63 research outputs found

    ADIPLS -- the Aarhus adiabatic oscillation package

    Full text link
    Development of the Aarhus adiabatic pulsation code started around 1978. Although the main features have been stable for more than a decade, development of the code is continuing, concerning numerical properties and output. The code has been provided as a generally available package and has seen substantial use at a number of installations. Further development of the package, including bringing the documentation closer to being up to date, is planned as part of the HELAS Coordination Action.Comment: Astrophys. Space Sci., in the pres

    Cabinet-Makers' Awareness and Usage of Rainforest Cabinet Timbers in Queensland

    Get PDF
    This paper reports findings of surveys into the usage of, and attitudes to, rainforest cabinet timbers by cabinet-makers in Queensland, Australia. In determining policies to promote growing of native rainforest trees on private land, it is necessary to know the market requirements for various cabinet species. The species most in demand by cabinet-makers are identified in this paper. Suitability and availability are found to be important determinants of cabinet-maker demand for timber. The species being planted in north Queensland are not a close match with those predicted by cabinet-makers to be in greatest demand in the future

    A High Resolution Method for Measuring Cosmic Ray Composition beyond 10 TeV

    Get PDF
    The accurate determination of the elemental composition of cosmic rays at high energies is expected to provide crucial clues on the origin of these particles. Previous direct measurements of composition have been limited by experiment collecting power, resulting in marginal statistics above 101410^{14} eV, precisely the region where the ``knee'' of the cosmic-ray energy spectrum is starting to develop. In contrast, indirect measurements using extensive air showers can produce sufficient statistics in this region but generate elemental measurements which have relatively large uncertainties. Here we discuss a technique which has become possible through the use of modern ground-based Cerenkov imaging detectors. We combine a measurement of the Cerenkov light produced by the incoming cosmic-ray nucleus in the upper atmosphere with an estimate of the total nucleus energy produced by the extensive air shower initiated when the particle interacts deeper in the atmosphere. The emission regions prior to and after the first hadronic interaction can be separated by an imaging Cerenkov system with sufficient angular and temporal resolution. Monte Carlo simulations indicate an expected charge resolution of ΔZ/Z<5\Delta Z/Z <5% for incident iron nuclei in the region of the ``knee'' of the cosmic-ray energy spectrum. This technique also has the intriguing possibility to unambiguously discover nuclei heavier than iron at energies above 1014^{14} eV. The identification and rejection of background produced by charged particles in ground based gamma-ray telescopes is also discussed.Comment: 26 pages 11 figures. Final version, Accepted in Astroparticle Physics 11/21/00. Fixed a few typos and a bad caption, added a short paragraph at en

    Mathematical Models of Incompressible Fluids as Singular Limits of Complete Fluid Systems

    Get PDF
    A rigorous justification of several well-known mathematical models of incompressible fluid flows can be given in terms of singular limits of the scaled Navier-Stokes-Fourier system, where some of the characteristic numbers become small or large enough. We discuss the problem in the framework of global-in-time solutions for both the primitive and the target system. © 2010 Springer Basel AG

    Propagation of leaky MHD waves at discontinuities with tilted magnetic field

    Get PDF
    We investigate the characteristics of magneto-acoustic surface waves propagating at a single density interface, in the presence of an inclined magnetic field. For linear wave propagation, the dispersion relation is obtained and analytical solutions are derived for small inclination angle. The inclination of the field renders the frequency of the waves complex, where the imaginary part describes wave attenuation, due to lateral energy leakage
    corecore