Physical conditions in low-ionization regions of the Orion Nebula

被引:47
作者
Baldwin, JA
Crotts, A
Dufour, RJ
Ferland, GJ
Heathcote, S
Hester, JJ
Korista, KT
Martin, PG
ODell, CR
Rubin, RH
Tielens, AGGM
Verner, DA
Verner, EM
Walter, DK
Wen, Z
机构
[1] COLUMBIA UNIV,DEPT ASTRON,NEW YORK,NY 10027
[2] RICE UNIV,HOUSTON,TX 77251
[3] UNIV KENTUCKY,LEXINGTON,KY 40503
[4] ARIZONA STATE UNIV,TEMPE,AZ 85287
[5] UNIV TORONTO,CANADIAN INST THEORET ASTROPHYS,TORONTO,ON M5S 3H8,CANADA
[6] NASA,AMES RES CTR,MOFFETT FIELD,CA 94035
[7] S CAROLINA STATE UNIV,DEPT PHYS SCI,ORANGEBURG,SC 29117
基金
美国国家科学基金会;
关键词
ISM; abundances; atoms; H II regions; individual (Orion Nebula);
D O I
10.1086/310245
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
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 (approximate to 10(4) 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.
引用
收藏
页码:L115 / L118
页数:4
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