Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Infrared emission from dust in shocked gas

Journal Article · · Astrophys. J.; (United States)
DOI:https://doi.org/10.1086/158864· OSTI ID:6116691
The cooling effects of dust in shock-heated gas, and the resulting infrared emission spectra, are computed for a realistic two-component (silicate and carbon) model for interstellar dust with the power-law size distribution proposed by Mathis, Rumpl, and Nordsieck. The infrared and far-infrared opacity of this grain model is discussed, and Planck-averaged emissivities are evaluated for both grain constituents. Thermally averaged accommodation coefficients for electrons and ions are obtained. Grain destruction is included in the calculations. Dust is an important coolant for shock speeds v/sub s/> or approx. =200 km s/sup -1/, radiating up to approx.17% of the shock energy in the infrared. Supernova-driven shock waves in our Galaxy with v/sub s/> or approx. =200 km s/sup -1/ advancing into clouds with preshock density n/sub H/ /sup 0/> or approx. =10/sup 2/ cm/sup -3/ should be detectable with current infrared instrumentation; for n/sub H/ /sup 0/> or approx. =10/sup 3/ cm/sup -3/ the 9.7 ..mu..m and 18 ..mu..m silicate emission features are predicted to be prominent.
Research Organization:
Institute for Advanced Study
OSTI ID:
6116691
Journal Information:
Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 245:3; ISSN ASJOA
Country of Publication:
United States
Language:
English