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Laboratory Results on Polarization Properties of Elongated Particles and Comparisons to Dust in the Tail of Comet Ikeya-Seki (1965 VIII)

Published online by Cambridge University Press:  12 April 2016

Bo.Å.S. Gustafson*
Affiliation:
Space Astronomy Laboratory, University of Florida, 1810 NW 6th Street Gainesville, Florida 32609, U.S.A.

Abstract

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Data obtained through microwave analog measurements are used to compare optical polarization characteristics of silicate particles ranging in shape from spheroids and cylinders to chains of spheres. It is confirmed that the dependence of the degree of polarization on scattering angle is a powerful indicator of particle shape. The reversal and steep gradient in the degree of polarization found by Weinberg and Beeson (1976a,b) in the dust tail of comet Ikeya-Seki (1965 VIII) is suggestive of laboratory measurements corresponding to 1.6 μm long, 0.4 μm in diameter silicate cylinders.

Type
IV. Optical Studies of Dust
Copyright
Copyright © Reidel 1985

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