NGC 7538 IRS 2 is a compact H ii region and recent star formation source, with a shell morphology, lying on the border of the visible H ii region NGC 7538. We present a spectral cube of the [Ne ii] 12.8 $\mu$m emission line obtained with the TEXES spectrometer on Gemini North with velocity resolution ∼4 km s−1 and angular resolution ∼0.3 arcsec. The kinematics of the data cube show ionized gas flowing along multiple cavity walls. We have simulated the kinematics and structure of IRS 2 with a model of superimposed cavities created by outflows from embedded stars in a cloud with density gradients. Most of the cavities, including the largest that dominates IRS 2 structure, are associated with B-type stars; the outflow of the bright ionizing O star binary IRS 2a/b is small in extent and lies in a high-density clump. The IRS 2 model shows that the behaviour of an H ii region is not a matter of only the most massive star present; cloud clumpiness and activity of lower mass stars may determine the structure and kinematics.
- Award ID(s):
- 2006433
- NSF-PAR ID:
- 10282645
- Date Published:
- Journal Name:
- Monthly Notices of the Royal Astronomical Society
- Volume:
- 497
- Issue:
- 2
- ISSN:
- 0035-8711
- Page Range / eLocation ID:
- 1675 to 1683
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/mnras/staa1819
