Hostname: page-component-cd9895bd7-lnqnp Total loading time: 0 Render date: 2024-12-26T04:58:06.496Z Has data issue: false hasContentIssue false
  • English
  • Français

Cosmic X-Rays and Interstellar Dust

Published online by Cambridge University Press:  14 August 2015

Satio Hayakawa
Satio Hayakawa*
Affiliation:
Dept. of Physics, Nagoya University, Nagoya, Japan

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Observational results of cosmic diffuse X-rays are reviewed with particular emphasis on soft X-rays. The intensity distribution of soft X-rays over the celestial sphere indicates that the diffuse component of soft X-rays consists of an extra-galactic and a galactic component. The absorption of the soft X-rays in the interstellar medium results in heating and ionization of interstellar matter. The ionization rate by X-rays is estimated as about 10–16 s–1 per H atom.

The scattering of X-rays by interstellar dust grains produces a halo of an X-ray source and smears out the pulsation of X-ray emission. The scattering coefficient and the halo size are given for some typical grain models.

The possibility that the dust grains gain relativistic energy is suggested. It is speculated that the relativistic dust grains in metagalactic space may be responsible for cosmic rays of ultrahigh energies and also for the diffuse X-rays by the interactions with cosmic black-body radiation.

Type
Part VI Physical Processes, Theory and Experiment
Information
Symposium - International Astronomical Union , Volume 52: Interstellar Dust and Related Topics , 1973 , pp. 283 - 296
Copyright
Copyright © Reidel 1973 

References

Bleeker, J. A. M. and Deerenberg, A. J. M.: 1970, Astrophys. J. 159, 215.CrossRefGoogle Scholar
Bleeker, J. A. M., Deerenberg, A. J. M., Yamashita, K., Hayakawa, S., Kato, T., and Tanaka, Y.: 1973, in preparation. Google Scholar
Brown, J. and Gould, R. J.: 1970, Phys. Rev. D1, 2252.Google Scholar
Danjo, A., Hayakawa, S., Ideka, M., Makino, F., Tanaka, Y., Agrawal, P. C., Gokhale, G. S., and Sreekantan, B. V.: 1970, Space Research XI, 1373.Google Scholar
Davidsen, A., Shulman, S., Fritz, G., Meekins, J. F., Henry, R. C., and Friedman, H.: 1972, Astrophys. J. 177, 629.CrossRefGoogle Scholar
Gorenstein, P. and Tucker, W. H.: 1972, Astrophys. J. 176, 333.CrossRefGoogle Scholar
Hayakawa, S.: 1970, Prog. Theor. Phys. 43, 1224.CrossRefGoogle Scholar
Hayakawa, S., Kato, T., Makino, F., Ogawa, H., Tanaka, Y., Yamashita, K., Matsuoka, M., Miyamoto, S., Oda, M., and Ogawara, Y.: 1971, Astrophys. Space Sci. 12, 789.CrossRefGoogle Scholar
Hayakawa, S.: 1972a, Astrophys. Space Sci. 16, 238.CrossRefGoogle Scholar
Hayakawa, S.: 1972b, in Bradt, H. and Giacconi, R. (eds.), ‘X- and Gamma-Ray Astronomy’, IAU Symp. 55, 235.Google Scholar
Kato, T.: 1972, Astrophys. Space Sci. 16, 478.CrossRefGoogle Scholar
Makino, F.: 1970, Astrophys. Space Sci. 8, 251.CrossRefGoogle Scholar
Naranan, S. and Shah, G. A.: 1970, Nature 225, 836.CrossRefGoogle Scholar
Overbeck, J. W.: 1965, Astrophys. J. 141, 864.CrossRefGoogle Scholar
Ryter, Ch.: 1970, Nature 226, 1040.CrossRefGoogle Scholar
Slysh, V. I.: 1969, Nature 224, 159.CrossRefGoogle Scholar
Spitzer, L.: 1949, Phys. Rev. 76, 583.CrossRefGoogle Scholar
Spitzer, L. and Scott, E. H.: 1969, Astrophys. J. 158, 161.CrossRefGoogle Scholar
Vette, J., Gruber, D., Matteson, J. L., and Peterson, L. E.: 1970, Astrophys. J. 160, L161.CrossRefGoogle Scholar