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Extinction curves for graphite-silicate grain mixtures

Published online by Cambridge University Press:  14 August 2015

N.C. Wickramasinghe
N.C. Wickramasinghe*
Affiliation:
Institute of Theoretical Astronomy, University of Cambridge, Cambridge, England

Abstract

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Mixtures of graphite particles ejected from carbon stars and silicates from oxygen-rich giants are capable of producing excellent fits to the observed interstellar extinction curve. The fits extend over the entire wavelength range of the observations, and include a hump at ~ 2200 Å in the ultraviolet due to the graphite components of the mixtures. The agreement with the observed extinction curve remains good if the small silicate particles acquire mantles of either ice or solid H2. If no mantles are present around the silicate grains comparable mass densities of graphite and silicates are indicated; if mantles of either ice or solid H2 are present the mass density of silicates may be an order of magnitude below that of graphite in the interstellar medium.

Type
Part I: Stellar Fluxes
Information
Symposium - International Astronomical Union , Volume 36: Ultraviolet Stellar Spectra and Related Ground-Based Observations , 1970 , pp. 42 - 49
Copyright
Copyright © Reidel 1970 

References

Bless, R. C., Code, A. D., and Houck, T. E.: 1968, Astrophys. J. 153, 561.Google Scholar
Bless, R. C. and Savage, B. D.: 1969, This Symposium, p. 28.Google Scholar
Danielson, R. E., Woolf, N. J., and Gaustad, J. E.: 1965, Astrophys. J. 141, 116.Google Scholar
Gilman, R. C.: 1969, Astrophys. J. 155, L185.Google Scholar
Hoyle, F. and Wickramasinghe, N. C.: 1962, Monthly Notices Roy. Astron. Soc. 124, 417.Google Scholar
Hoyle, F. and Wickramasinghe, N. C.: 1969, Nature 223, 459.Google Scholar
Johnson, H. L.: 1965, Astrophys. J. 141, 923.CrossRefGoogle Scholar
Knacke, R. F., Gaustad, J. E., Gillett, F. C., and Stein, W. A.: 1969, Astrophys. J. 155, L189.Google Scholar
Nandy, K.: 1964, Publ. Roy. Observ. Edin. 3, No. 6.Google Scholar
Ney, E. P. and Allen, D. A.: 1969, Astrophys. J. 155, L193.Google Scholar
Stecher, T. P.: 1965, Astrophys. J. 142, 1683.Google Scholar
Stecher, T. P.: 1969, This Symposium, p. 24. Astrophys. J. 157, L125.CrossRefGoogle Scholar
Stecher, T. P. and Donn, B.: 1965, Astrophys. J. 142, 1681.Google Scholar
Stein, W. A. and Gillett, F. C.: 1969, Astrophys. J. 155, L197.Google Scholar
Taft, E. A. and Phillipp, H. R.: 1965, Phys. Rev. 138A, 197.Google Scholar
Wickramasinghe, N. C.: 1967, Interstellar Grains, Chapman and Hall, London.Google Scholar
Wickramasinghe, N. C. and Guillaume, C.: 1965, Nature 207, 366.Google Scholar
Wickramasinghe, N. C. and Krishna Swamy, K. S.: 1969, Monthly Notices Roy. Astron. Soc. 144, 41.Google Scholar
Wickramasinghe, N. C. and Nandy, K.: 1968, Nature 219, 1347.CrossRefGoogle Scholar
Williams, D. A.: 1968, Astrophys. J. 151, 935.Google Scholar
Woolf, N. J. and Ney, E. P.: 1969, Astrophys. J. 155, L181.Google Scholar