Spitzer Observations of Molecular Hydrogen in Interacting Supernova Remnants

Details Spitzer Observations of Molecular Hydrogen in Interacting Supernova Remnants Spitzer Observations of Molecular Hydrogen in Interacting Supernova Remnants

2009-01-12

arxiv.org/abs/0901.1622v1

Astrophys.J.694:1266-1280,2009

Astronomy and Astrophysics

Astrophysics

Solar and Stellar Astrophysics

Accepted to Ap J and scheduled for 2009 April 1 v694 issue. LaTeX, 27 pages with 11 figures

Scientific paper

10.1088/0004-637X/694/2/1266

With Spitzer IRS we have obtained sensitive low-resolution spectroscopy from 5 to 35 microns for six supernova remnants (SNRs) that show evidence of shocked molecular gas: Kes 69, 3C 396, Kes 17, G346.6-0.2, G348.5-0.0 and G349.7+0.2. Bright, pure-rotational lines of molecular hydrogen are detected at the shock front in all remnants, indicative of radiative cooling from shocks interacting with dense clouds. We find the excitation of H2 S(0)-S(7) lines in these SNRs requires two non-dissociative shock components: a slow, 10 km/s C- shock through clumps of density 10^6 cm^-3, and a faster, 40-70 km/s C- shock through a medium of density 10^4 cm^-3. The ortho-to-para ratio for molecular hydrogen in the warm shocked gas is typically found to be much less than the LTE value, suggesting that these SNRs are propagating into cold quiescent clouds. Additionally a total of thirteen atomic fine-structure transitions of Ar+, Ar++, Fe+, Ne+, Ne++, S++, and Si+ are detected. The ionic emitting regions are spatially segregated from the molecular emitting regions within the IRS slits. The presence of ionic lines with high appearance potential requires the presence of much faster, dissociative shocks through a lower density medium. The IRS slits are sufficiently wide to include regions outside the SNR which permits emission from diffuse gas around the remnants to be separated from the shocked emission. We find the diffuse molecular hydrogen gas projected outside the SNR is excited to a temperature of 100 to 300 K with a warm gas fraction of 0.5 to 15 percent along the line of sight.

Affiliated with

Also associated with

No associations

Rating

Spitzer Observations of Molecular Hydrogen in Interacting Supernova Remnants does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Spitzer Observations of Molecular Hydrogen in Interacting Supernova Remnants, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spitzer Observations of Molecular Hydrogen in Interacting Supernova Remnants will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-533038