DUST PROCESSING IN SUPERNOVA REMNANTS: SPITZER MIPS SPECTRAL ENERGY DISTRIBUTION AND INFRARED SPECTROGRAPH OBSERVATIONS

Journal Article · Sun Nov 20 00:00:00 EST 2011 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/742/1/7; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA)· OSTI ID:21612656

Andersen, M ^[1]; Rho, J; Reach, W T ^[2]; Hewitt, J W ^[3]

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1. Spitzer Science Center, California Institute of Technology, Pasadena, CA 91125 (United States)
2. SOFIA/USRA NASA Ames Research Center, Mail Stop N211-3, Moffett Field, CA 94035 (United States)
3. NASA Goddard Space Flight Center, Mail Code 662, Greenbelt, MD 20771 (United States)

We present Spitzer Multiband Imaging Photometer (MIPS) spectral energy distribution (SED) and Infrared Spectrograph (IRS) observations of 14 Galactic supernova remnants (SNRs) previously identified in the GLIMPSE survey. We find evidence for SNR/molecular cloud interaction through detection of [O I] emission, ionic lines, and emission from molecular hydrogen. Through blackbody fitting of the MIPS SEDs we find the large grains to be warm, 29-66 K. The dust emission is modeled using the DUSTEM code and a three-component dust model composed of populations of big grains (BGs), very small grains (VSGs), and polycyclic aromatic hydrocarbons. We find the dust to be moderately heated, typically by 30-100 times the interstellar radiation field. The source of the radiation is likely hydrogen recombination, where the excitation of hydrogen occurred in the shock front. The ratio of VSGs to BGs is found for most of the molecular interacting SNRs to be higher than that found in the plane of the Milky Way, typically by a factor of 2-3. We suggest that dust shattering is responsible for the relative overabundance of small grains, in agreement with the prediction from dust destruction models. However, two of the SNRs are best fitted with a very low abundance of carbon grains to silicate grains and with a very high radiation field. A likely reason for the low abundance of small carbon grains is sputtering. We find evidence for silicate emission at 20 {mu}m in their SEDs, indicating that they are young SNRs based on the strong radiation field necessary to reproduce the observed SEDs.

• OSTI ID: 21612656
• Journal Information: Astrophysical Journal, Vol. 742, Issue 1; Other Information: DOI: 10.1088/0004-637X/742/1/7; Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ABUNDANCE
DUSTS
ENERGY SPECTRA
HYDROGEN
MILKY WAY
PHOTOMETERS
POLYCYCLIC AROMATIC HYDROCARBONS
RECOMBINATION
SILICATES
SUPERNOVA REMNANTS
AROMATICS
COSMIC RADIO SOURCES
ELEMENTS
GALAXIES
HYDROCARBONS
MEASURING INSTRUMENTS
NONMETALS
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
SILICON COMPOUNDS
SPECTRA