6 research outputs found

    Galactic Cosmic Rays - Theory and Interpretation

    Get PDF
    The arguments surrounding the Galactic component of the cosmic rays, the energy budget, questions of composition, spectral features, anisotropy, sources etc, will be critically examined. We are moving into a new phase in the study of the Galactic cosmic rays where it is becoming clear that precision measurements are revealing new, and in some cases unexpected, features which are forcing us to develop more sophisticated models for their production and propagation. The fundamental concepts however appear to be quite solid and have changed remarkably little in the more than fifty years since Ginzburg and Syrovatskii's classic "The Origin of Cosmic Rays".Comment: Community peer review solicited - final version due for submission mid Se

    Galactic Cosmic Rays from Supernova Remnants (I) - a Cosmic Ray Composition controlled by Volatility and Mass-to-Charge Ratio

    Full text link
    This is the first of a series of papers analysing the Galactic Cosmic Ray composition and origin. We show that the Galactic Cosmic Ray source (GCRS) composition is best described in terms of (i) a general enhancement of the refractory elements relative to the volatile ones, and (ii) among the volatile elements, an enhancement of the heavier elements relative to the lighter ones; this mass dependence most likely reflects a mass-to-charge (A/Q) dependence of the acceleration efficiency; among the refractory elements, there is NO such enhancement of heavier species, or only a much weaker one. We regard as coincidental the similarity between the GCRS composition and that of the solar corona, which is biased according to first ionization potential. In a companion paper, this GCRS composition is interpreted in terms of an acceleration by supernova shock waves of interstellar and/or circumstellar (eg Ne22 rich Wolf-Rayet wind) gas-phase and especially dust material.Comment: 23 pages plain TeX and 6 postscript figures, to appear in ApJ, also available from ftp://wonka.physics.ncsu.edu/pub/elliso
    corecore