Structure of the interstellar medium around Cas A

Abstract

We present a three-year series of observations at 24 microns with the Spitzer Space Telescope of the interstellar material in a 200 x 200 arcmin square area centered on Cassiopeia A. Interstellar dust heated by the outward light pulse from the supernova explosion emits in the form of compact, moving features. Their sequential outward movements allow us to study the complicated three-dimensional structure of the interstellar medium (ISM) behind and near Cassiopeia A. The ISM consists of sheets and filaments, with many structures on a scale of a parsec or less. The spatial power spectrum of the ISM appears to be similar to that of fractals with a spectral index of 3.5. The filling factor for the small structures above the spatial wavenumber k ~ 0.5 cycles/pc is only ~ 0.4%.

29 pages including 10 figures; accepted by The Astrophysical Journal

References in corpus (5)

• Molecular Cloud Evolution II. From cloud formation to the early stages of star formation in decaying conditions
• Magnetically Dominated Strands of Cold Hydrogen in the Riegel-Crutcher Cloud
• No cold dust within the supernova remnant Cassiopeia A
• Infrared Echoes near the Supernova Remnant Cassiopeia A
• Mapping and Mass Measurement of the Cold Dust in NGC 205 with Spitzer

Cited by in corpus (6)

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• The Youngest Galactic Supernova Remnant: G1.9+0.3
• Discovery of a 112 ms X-ray Pulsar in Puppis A: Further Evidence of Neutron Stars Weakly Magnetized at Birth
• A dedicated Chandra ACIS observation of the central compact object in the Cassiopeia A supernova remnant
• Infrared Echoes Reveal the Shock Breakout of the Cas A Supernova