Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-09-03
Astrophys.J.636:859-872,2006
Astronomy and Astrophysics
Astrophysics
17 pages including 3 tables and 7 figures. To appear in ApJ
Scientific paper
10.1086/498092
Hubble Space Telescope images of the young Galactic supernova remnant Cassiopeia A reveal a far larger population of outlying, high-velocity knots of ejecta with a broader range of chemical properties than previously suspected. We identify three main classes of outer ejecta: 1) Knots dominated by [N II] 6548,6583 emission; 2) Knots dominated by oxygen emission lines especially [O II] 7319,7330; and 3) Knots with emission line strengths similar to the [S II] strong FMK ejecta commonly seen in the main emission shell. The discovery of a significant population of O-rich ejecta situated in between the suspected N-rich outer photospheric layer and S-rich FMK-like ejecta suggests that the Cas A progenitor's chemical layers were not completely disrupted by the supernova explosion outside of the remnant's NE and SW high velocity `jet' regions. In addition, we find the majority of O-rich outer ejecta at projected locations out beyond (v = 6500 - 9000 km/s) the remnant's fastest moving Fe-rich X-ray emission material (6000 km/s) seen in Chandra and XMM data along the eastern limb. This suggests that penetration of Fe-rich material up through the S and Si-rich mantle did not extend past the progenitor's N or O-rich outer layers for at least this section of the remnant.
Borkowski Kazimierz J.
Chevalier Roger A.
Dopita Mike A.
Fesen Robert A.
Gerardy Christopher L.
No associations
LandOfFree
Discovery of Outlying, High-Velocity Oxygen-Rich Ejecta in Cassiopeia A 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 Discovery of Outlying, High-Velocity Oxygen-Rich Ejecta in Cassiopeia A, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Discovery of Outlying, High-Velocity Oxygen-Rich Ejecta in Cassiopeia A will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-56479