Astronomy and Astrophysics – Astrophysics
Scientific paper
2002-02-06
Astrophys.J. 581 (2002) 1225-1235
Astronomy and Astrophysics
Astrophysics
33 pages, 12 figures; to appear in the Astrophysical Journal
Scientific paper
10.1086/344363
Chandra X-ray Observatory (CXO) images have revealed that the X-ray emitting regions of the molecule-rich young planetary nebulae (PNs) BD+30 3639 (BD+30) and NGC 7027 are much more asymmetric than their optical nebulosities. To evaluate the potential origins of these X-ray asymmetries, we analyze X-ray images of BD+30, NGC 7027, and another planetary nebula resolved by CXO, NGC 6543, within specific energy bands. Image resolution has been optimized by sub-pixel repositioning of individual X-ray events. The resulting subarcsecond-resolution images reveal that the soft (E < 0.7 keV) X-ray emission from BD+30 is more uniform than the harder emission, which is largely confined to the eastern rim of the optical nebula. In contrast, soft X-rays from NGC 7027 are highly localized and this PN is more axially symmetric in harder emission. The broad-band X-ray morphologies of BD+30 and NGC 7027 are highly anticorrelated with their distributions of visual extinction, as determined from high-resolution, space- and ground-based optical and infrared imaging. Hence, it is likely that the observed X-ray asymmetries of these nebulae are due in large part to the effects of nonuniform intranebular extinction. However, the energy-dependent X-ray structures in both nebulae and in NGC 6543 -- which is by far the least dusty and molecule-rich of the three PNs, and displays very uniform intranebular extinction -- suggests that other mechanisms, such as the action of collimated outflows and heat conduction, are also important in determining the detailed X-ray morphologies of young planetary nebulae.
Gatley Ian
Kastner Joel H.
Li Jingqiang
Merrill Michael K.
Soker Noam
No associations
LandOfFree
On the Asymmetries of Extended X-ray Emission from Planetary Nebulae 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 On the Asymmetries of Extended X-ray Emission from Planetary Nebulae, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On the Asymmetries of Extended X-ray Emission from Planetary Nebulae will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-649496