Interstellar extinction and polarization in the infrared

Journal Article · Sun Jul 01 04:00:00 EDT 1990 · Astrophysical Journal; (USA)

DOI:https://doi.org/10.1086/168896· OSTI ID:6596927

Martin, P G; Whittet, D C.B. ^[1]

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1. Canadian Institute for Theoretical Astrophysics, Toronto (Canada) York Univ., Downsview (Canada)

The wavelength dependences of interstellar continuum extinction and polarization in the range 0.35-5 microns are examined. The existence of a universal extinction curve with power law index of about 1.8 extending from the near-IR to at least 5 microns appears to be established for both diffuse and dense cloud dust. The polarization yields evidence for some degree of universality in the 1.6-5 micron regime which may be represented by a power law with index 1.5-2.0, encompassing that for extinction. The form of the polarization curve in the IR seems independent of the wavelength at which the degree of polarization peaks in the optical, implying that variations in that wavelength are caused by changes in the optical properties of the particle at blue-visible rather than IR wavelengths. It is argued that the more significant alterations of the grain size distribution from one environment to another occur for the smaller particles. 47 refs.

• OSTI ID: 6596927
• Journal Information: Astrophysical Journal; (USA), Journal Name: Astrophysical Journal; (USA) Vol. 357; ISSN ASJOA; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABSORPTION
COSMIC DUST
COSMIC GASES
DUSTS
ELECTROMAGNETIC RADIATION
ENERGY SPECTRA
FLUIDS
GASES
INFRARED RADIATION
INTERSTELLAR SPACE
MASS
NEAR INFRARED RADIATION
PARTICLE SIZE
POLARIZATION
RADIATIONS
SIZE
SPACE
SPECTRA
STELLAR RADIATION