Astrophysics and Space Science

, Volume 24, Issue 1, pp 279–288 | Cite as

Extragalactic cosmic rays and the galactic magnetic field

  • E. N. Parker


The origin and behavior of cosmic rays in the Galaxy depends crucially upon whether the galactic magnetic field has a closed topology, as does the field of Earth, or whether a major fraction of the lines of force connect into extragalactic space. If the latter, then cosmic rays could be of extragalactic origin, or they could be of galactic origin, detained in the Galaxy by the scattering offered by hydromagnetic waves, etc. If, on the other hand, the field is largely closed, then cosmic rays cannot be of extragalactic origin (at least below 1016 eV). They must be of galactic origin and escape because their collective pressure inflates the galactic field and they push their way out.

This paper examines the structure of a galactic field that opens initially into intergalactic space and, with the inclusion of turbulent diffusion, finds no possibility for maintaining a significant magnetic connection with an extragalactic field. Unless some mechanism can be found, we are forced to the conclusion that the field is closed, that cosmic rays are of galactic origin, and that cosmic rays escape from the Galaxy only by pushing their way out.


Magnetic Field Major Fraction Turbulent Diffusion Hydromagnetic Wave Magnetic Connection 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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  1. Axford, W. I. and Holzer, T. E.: 1970,Ann. Rev. Astron. Astrophys. 8, 31.Google Scholar
  2. Brecher, K. and Burbidge, G. R.: 1972,Astrophys. J. 174, 253.Google Scholar
  3. Burke, J. A.: 1968,Monthly Notices Roy. Astron. Soc. 140, 241.Google Scholar
  4. Dungey, J. W.: 1958,Cosmic Electrodyn., Cambridge University Press, Cambridge, pp. 98, 1259.Google Scholar
  5. Dungey, J. W.: 1963,Planetary Space Sci. 10, 233.Google Scholar
  6. Elliot, H., Thambyahpillai, T., and Peacock, D. S.: 1969,Acta. Phys. Hung. 29, Suppl.1, 691.Google Scholar
  7. Gradshteyn, I. S. and Ryshik, I. M.: 1965,Tables of Integrals, Series, and Products, Academic Press, New York, p. 307, No. 3.325.Google Scholar
  8. Johnson, H. E. and Axford, W. I.: 1971,Astrophys. J. 165, 381.Google Scholar
  9. Jokipii, J. R. and Parker, E. N.:Astrophys. J. 155, 799.Google Scholar
  10. Kulsrud, R. M. and Pearce, W. D.: 1968,Astron. J. 73, 522.Google Scholar
  11. Kulsrud, R. M. and Pearce, W. D.: 1969,Astrophys. J. 156, 445.Google Scholar
  12. Mestel, L.: 1965,Quart. J. Roy. Astron. Soc. 6, 161, 265.Google Scholar
  13. Oort, J. H.: 1969,Nature 224, 1158.Google Scholar
  14. Parker, E. N.: 1965,Astrophys. J. 142, 584.Google Scholar
  15. Parker, E. N.: 1967,Astrophys. J. 149, 535.Google Scholar
  16. Parker, E. N.: 1969,Space Sci. Rev. 9, 651.Google Scholar
  17. Parker, E. N.: 1971a,Astrophys. J. 163, 255.Google Scholar
  18. Parker, E. N.: 1971b,Astrophys. J. 163, 279.Google Scholar
  19. Parker, E. N.: 1971c,Astrophys. J. 166, 295.Google Scholar
  20. Parker, E. N.: 1973a,Astrophys. J. 180, 247.Google Scholar
  21. Parker, E. N.: 1973b,Astrophys. Space Sci. 22, 279.Google Scholar
  22. Parker, E. N.: 1973c,J. Plasma Phys. 9, 49.Google Scholar
  23. Petschek, H. E.: 1964, in W. N. Hess (ed.), ‘The Physics of Solar Flares’,AAS-NASA Symp., 28–30 Oct. 1963; Greenbelt, Md. NASA SP-50.Google Scholar
  24. Piddington, J. H.: 1972,Cosmic Electrodyn. 3, 60, 129.Google Scholar
  25. Ramaty, R., Reames, D. V., and Lingenfelter, R. E.: 1970,Phys. Rev. Letters 24, 913.Google Scholar
  26. Shapiro, M. and Silverberg, R.: 1970,Ann. Rev. Nucl. Sci. 20, 323.Google Scholar
  27. Weiss, N. O.: 1966,Proc. Roy. Soc. London A,293, 310.Google Scholar
  28. Wentzel, D. G.: 1969a,Astrophys. J. 156, 303.Google Scholar
  29. Wentzel, D. G.: 1969b,Astrophys. J. Letters 156, L91.Google Scholar
  30. Wentzel, D. G.: 1969c,Astrophys. J. 157, 545.Google Scholar
  31. Wentzel, D. G.: 1971,Astrophys. J. 163, 503.Google Scholar
  32. Yeh, T. and Axford, W. I.: 1970,J. Plasma Phys. 4, 207.Google Scholar

Copyright information

© D. Reidel Publishing Company 1973

Authors and Affiliations

  • E. N. Parker
    • 1
  1. 1.Dept. of Physics, Dept. of Astronomy and AstrophysicsUniversity of ChicagoChicagoUSA

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