Abstract
We reexamine the spectroscopic underpinnings of recent suggestions that [O I] and [Fe II] lines from the Orion H II region are produced in gas where the iron-carrying grains have been destroyed and the electron density is surprisingly high. Our new observations show that previous detections of [O I] 5577 were dominated by telluric emission. Our limits are consistent with a moderate density (≈104 cm-3) photoionized gas. We show that a previously proposed model of the Orion H II region reproduces the observed [O I] and [Fe II] spectrum. These lines are fully consistent with formation in a dusty region of moderate density.
Original language | English |
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Pages (from-to) | L115-L118 |
Journal | Astrophysical Journal |
Volume | 468 |
Issue number | 2 PART II |
DOIs | |
State | Published - Sep 10 1996 |
Bibliographical note
Funding Information:We thank STScI for its support through grants GO-4385, GO-5748, GO-6056, GO-6093, and AR-06403.01-95A. R. J. D. and G. J. F. acknowledge NASA/Ames Research Center Interchange Grants NCC2-5008 and NCC2-5028, respectively. Research in Nebular Astrophysics at the University of Kentucky is supported by the National Science Foundation through award AST 93-19034. We are grateful to D. Oster-brock, L. Lucy, A. Pradhan, and M. Bautista for useful discussions.
Keywords
- ISM: H II regions
- ISM: abundances
- ISM: atoms
- ISM: individual (Orion Nebula)
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science