Sign on

SAO/NASA ADS Astronomy Abstract Service

· Find Similar Abstracts (with default settings below)
· Electronic Refereed Journal Article (HTML)
· Full Refereed Journal Article (PDF/Postscript)
· References in the article
· Citations to the Article (14) (Citation History)
· Refereed Citations to the Article
· SIMBAD Objects (5)
· Also-Read Articles (Reads History)
·
· Translate This Page
Title:
A Near-Infrared Study of NGC 7538 IRS 1, 2, and 3
Authors:
Bloomer, John D.; Watson, Dan M.; Pipher, Judith L.; Forrest, William J.; Ali, B.; Greenhouse, Matthew A.; Satyapal, Shobita; Smith, Howard A.; Fischer, Jacqueline; Woodward, Charles E.
Publication:
The Astrophysical Journal, Volume 506, Issue 2, pp. 727-742. (ApJ Homepage)
Publication Date:
10/1998
Origin:
APJ
ApJ Keywords:
ISM: H II REGIONS, INFRARED: ISM: LINES AND BANDS, INFRARED: STARS, ISM: INDIVIDUAL (NGC 7538), OPEN CLUSTERS AND ASSOCIATIONS: INDIVIDUAL (NGC 7538), STARS: FORMATION
DOI:
10.1086/306268
Bibliographic Code:
1998ApJ...506..727B

Abstract

We present images of the cluster of embedded young stars designated NGC 7538 IRS 1, 2, and 3 in the J (1.25 μm), H (1.64 μm), and K (2.16 μm) broad bands; the 1.64 μm line of [Fe II]; the 2.12 μm and 2.25 μm lines of H_2; the 2.17 μm Brackett gamma H-recombination line; and the 3.29 μm ``unidentified'' dust feature. The NGC 7538 IRS 2 compact H II region, as seen in Brackett gamma line emission, possesses a cometary morphology. We find evidence for a shell-like distribution of [Fe II] line emission along the periphery of the compact H II region. This morphology and the observed intensity ratio I([Fe II] 1.64 μm)/I(Brgamma) imply that the [Fe II] line emission emanates from shocked stellar wind material. We observe arcs of H_2 line emission immediately exterior to the [Fe II] line emission shell and suggest that these arcs delineate molecular cloud material shocked via collision with the stellar wind. We observe larger arcs with centers of curvature displaced from each other and IRS 2, in broad-band-continuum, H_2-line, and 3.29 μm feature emission, and suggest that these arcs represent molecular gas (either shocked or UV-excited) and dust swept up during distinct episodes of stellar mass ejection. We submit that the morphological and energetic evidence favors a ``stellar wind bow shock'' interpretation, in which the motion of the central O star with respect to the surrounding molecular cloud, in conjunction with the star's high-velocity stellar wind and episodic mass ejection, gives rise to the observed general cometary morphology and circum-H II region emission.
Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)
   

Find Similar Abstracts:

Use: Authors
Title
Keywords (in text query field)
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
Physics
arXiv e-prints