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Far Infrared Emission from Galactic and Extragalactic Dust

Helou, George (1989) Far Infrared Emission from Galactic and Extragalactic Dust. In: Interstellar Dust. International Astronomical Union Symposium (IAUS). No.135. Springer Netherlands , Dordrecht, pp. 285-301. ISBN 9780792304494.

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This review examines the question of how similar far infrared and submillimeter dust properties are among galaxies including the Milky Way, and within the Milky Way. The IRAS data are examined, and no evidence is found for variations in the broad-band dust properties between 10 and 100 µm. Submillimeter data are examined in a search for a power-law index describing the emissivity of dust at λ > 100 µm. The data are consistent with a universal value of the index between 1 and 2. The evidence for large amounts of cold dust (10 to 15 K) in galaxies is reviewed and found quite soft in light of conflicting data. In most spiral galaxies, the dust-to-gas ratios are comparable to their values in the Milky Way, with a few well-documented exceptions such as the Magellanic Clouds and Blue Compact Dwarf galaxies, which have a lower ratio. No compelling evidence is found for gradients in the dust-to-gas ratio within disks of galaxies. Very small grains with fluctuating temperatures appear to be present in all galaxies examined, and to behave just like those observed in the Milky Way.

Item Type:Book Section
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Helou, George0000-0003-3367-3415
Additional Information:© IAU 1989. I would like to thank Helen Knudsen, Rosanne Hernandez and the IPAC Library for help with the literature search and collection of references, Mary Ellen Barba for help with the manuscript, and François Boulanger, Chas Beichman and Tom Soifer for helpful comments on the manuscript. This work was supported as part of the IRAS Extended Mission by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.
Group:Infrared Processing and Analysis Center (IPAC)
Funding AgencyGrant Number
Subject Keywords:Interstellar Medium; Molecular Cloud; Spiral Galaxy; Radio Galaxy; Large Magellanic Cloud
Series Name:International Astronomical Union Symposium (IAUS)
Issue or Number:135
Record Number:CaltechAUTHORS:20201008-131242705
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:105939
Deposited By: George Porter
Deposited On:08 Oct 2020 21:24
Last Modified:16 Nov 2021 18:48

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