Astrophysics and Space Science

, Volume 39, Issue 1, pp 151–156 | Cite as

The optics of spherically stratified graphite grains

  • N. C. Wickramasinghe
Article
Received:

Abstract

Extinction and scattering efficiencies are calculated for spherically stratified graphite spheres using formulae which are valid in the small particle limit. The resulting extinction curve for this model is shown to peak at an ultraviolet wavelengthλ-1=4.8−5μ-1 close to that for the case of the less probable plane stratified model of a graphite sphere. The albedo in the present model is higher than that calculated for the plane stratified case by a factor 1.5–2 in the far ultraviolet. Extinction curves are also obtained for the case of a dielectric sphere surrounded by a thin graphite film, and it is shown that there now is an extinction minimum atλ-1≃4.6μ-1.

Keywords

Graphite Small Particle Present Model Extinction Curve Probable Plane 
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Copyright information

© D. Reidel Publishing Company 1976

Authors and Affiliations

  • N. C. Wickramasinghe
    • 1
  1. 1.Dept. of Applied Mathematics and AstronomyUniversity CollegeCardiffWales, U.K.

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