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The composition of Galactic Cosmic Ray Sources (GCRS) shows the following features: (i) an enhancement of the refractory elements
relative to the volatile ones, and (ii) an enhancement of the heavier volatile elements relative to the lighter ones; this
mass dependence should reflect a mass-to-charge (A/Q) dependence of the acceleration efficiency; among the refractory elements,
there is only a very weak enhancement of heavier species, or none at all. We consider it fortuitous that the GCRS composition
resembles that of the solar corona, which is biased according to first ionization potential. In a companion paper by Ellison
et al. (1998, this issue), this GCRS composition is interpreted in terms of a supernova shock wave acceleration of interstellar
and/or circumstellar (e.g., 22Ne-rich Wolf-Rayet wind) gas phase and especially dust grain material. These two papers summarize
and complement the content of two papers that recently appeared in Astrophys. J. (Meyer et al., 1997; Ellison et al., 1997).
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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Space Science Reviews - We summarize our model of galactic cosmic-ray (GCR) origin and acceleration, wherein a mixture of interstellar and/or circumstellar gas and dust is accelerated by a... 相似文献
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Diffusive shock acceleration is the theory of particle acceleration through multiple shock crossings. In order for this process to proceed at a rate that can be reconciled with observations of high-energy electrons in the vicinity of the shock, and for cosmic rays protons to be accelerated to energies up to observed galactic values, significant magnetic field amplification is required. In this review we will discuss various theories on how magnetic field amplification can proceed in the presence of a cosmic ray population. On both short and long length scales, cosmic ray streaming can induce instabilities that act to amplify the magnetic field. Developments in this area that have occurred over the past decade are the main focus of this paper. 相似文献
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L O'C Drury 《Space Science Reviews》1996,75(1-2):269-277
The possibility of observing gamma ray emission from supernova remnants is discussed. It is shown that this could be possible in the 100 MeV band accessible to satellite instruments, but that confusion with the Galactic background is a major problem. At TeV energies and with modern imaging atmospheric cherenkov telescopes the situation should be much better and at least some of the nearby remnants may be detectable. Positive detections in both bands would provide a decisive test of current theoretical ideas on particle acceleration in supernova remnants and the origin of the Galactic cosmic rays. 相似文献
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Klecker B. Mewaldt R.A. Bieber J.W. Cummings A.C. Drury L. Giacalone J. Jokipii J.R. Jones F.C. Krainev M.B. Lee M.A. Le Roux J.A. Marsden R.G. Mcdonald F.B. McKibben R.B. Steenberg C.D. Baring M.G. Ellison D.C. Lanzerotti L.J. Leske R.A. Mazur J.E. Moraal H. Oetliker M. Ptuskin V.S. Selesnick R.S. Trattner K.J. 《Space Science Reviews》1998,83(1-2):259-308
We review the observed properties of anomalous cosmic rays and the present status of our knowledge of the processes by which they originate. We compiled a comprehensive set of ACR energy spectral data from various spacecraft throughout the heliosphere during the passes of Ulysses over the poles of the Sun and present first results of a detailed modeling effort. In several contributions, we discuss the questions of injection and possible pre-acceleration of pickup ions, summarize new observations on the ionic charge composition, and present new results on the composition of minor ions in ACRs. 相似文献
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L. O’C. Drury D.E. Ellison F.A. Aharonian E. Berezhko A. Bykov A. Decourchelle R. Diehl G. Meynet E. Parizot J. Raymond S. Reynolds S. Spangler 《Space Science Reviews》2001,99(1-4):329-352
The main features of cosmic-ray source models and acceleration processes are reviewed, with special emphasis on the possible observational tests, through both composition analysis and multi-wavelength studies of supernova remnants. Non-linear effects in the context of supernova-induced diffusive shock acceleration are discussed, as well as collective acceleration effects induced by multiple supernova explosions inside superbubbles. 相似文献
7.
L. Drury 《Space Science Reviews》1983,36(1):57-60
The applicability of first and second order Fermi acceleration to electrons in supernova remnants is briefly examined. 相似文献
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