Hostname: page-component-84b7d79bbc-c654p Total loading time: 0 Render date: 2024-07-25T13:32:29.185Z Has data issue: false hasContentIssue false
  • English
  • Français

Interstellar Circular Polarization and the Composition of Interstellar Dust

Published online by Cambridge University Press:  14 August 2015

P. G. Martin
P. G. Martin*
Affiliation:
Institute of Theoretical Astronomy, Madingley Road, Cambridge, Englandcor1corresp
∗

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.

This paper shows that optical observations of circular polarization produced by aligned interstellar grains could yield valuable information about the grain material. The interstellar medium is known to be linearly dichroic from observations of interstellar linear polarization; many different grain models using a large variety of compositions can be found to reproduce these observations. Since the same aligned grains make the medium linearly birefringent, a small component of circular polarization can result from incident linearly polarized light if the position angle of the linear polarization does not coincide with either principal axis of the medium. Here calculations are presented to demonstrate that the wavelength of the circular polarization is sensitive to the imaginary part of the complex refractive index of the grain material. This provides an opportunity of investigating whether the grains are characteristically dielectric or metallic. Some possible observations are suggested.

Type
Part IV Interstellar Polarization
Information
Symposium - International Astronomical Union , Volume 52: Interstellar Dust and Related Topics , 1973 , pp. 161 - 167
Copyright
Copyright © Reidel 1973 

References

Coyne, G. and Gehrels, T.: 1967, Astron. J. 72, 892.Google Scholar
Dyck, H. M., Forrest, W. J., Gillett, F. C., Stein, W. A., Gehrz, R. D., and Woolf, N. J.: 1971, Astrophys. J. 165, 57.CrossRefGoogle Scholar
Greenberg, J. M.: 1968, Stars and Stellar Systems 7, 221.Google Scholar
Greenberg, J. M., Pedersen, N. E., and Pedersen, J. C.: 1961, J. Appl. Phys. 32, 233.Google Scholar
Kemp, J. C.: 1972, Astrophys J. Letters 175, L35.Google Scholar
Kemp, J. C.: 1973, this volume, p. 181.Google Scholar
Lind, A. C. and Greenberg, J. M.: 1966, J. Appl. Phys. 37, 3195.Google Scholar
Martin, P. G.: 1972, Monthly Notices Rox Astron. Soc. 159, 179.Google Scholar
Martin, P. G.: 1972, Paper presented at IAU Colloq. 23, Nov. 1972, Tucson, Ariz.Google Scholar
Martin, P. G., Illing, R., and Angel, J. R. P.: 1972, Monthly Notices Roy. Astron. Soc. 159, 191.Google Scholar
Serkowski, K.: 1962, Adv. Astron. Astrophys. 1, 290.Google Scholar
Serkowski, K.: 1970, Astrophys. J. 160, 1083.Google Scholar
Van de Hulst, H. C.: 1957, Light Scattering by Small Particles , Wiley, New York.Google Scholar