Detection of the [N ii] 122 and 205 Micron Lines: Densities in G333.6-0.2
Abstract
Measurements of the G333.6-0.2 H II region which include the first detection of the N II 122 micron forbidden line in an astronomical force and the first measurement of the N II 205 micron forbidden line in a discrete source are presented. Also considered are fine structure lines of forbidden S III, forbidden Fe III, forbidden Si II, forbidden Ne III, forbidden O III, forbidden N III, forbidden O I, and forbidden C II from 19 to 206 microns. It is concluded that the N II 122 and 205 microns forbidden line pair in a discrete astronomical source was detected for the first time. The emission in transitions is produced largely by low-ioninzation, low-density material not easily probed by other lines. Other FIR line pairs generally originate in higher density regions closer to the exciting force.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- August 1993
- DOI:
- 10.1086/172991
- Bibcode:
- 1993ApJ...413..237C
- Keywords:
-
- H Ii Regions;
- Infrared Astronomy;
- Interstellar Gas;
- Line Spectra;
- Nitrogen;
- Space Density;
- Electron Density Profiles;
- Gas Density;
- Astrophysics;
- ISM: H II REGIONS;
- ISM: INDIVIDUAL ALPHANUMERIC: G333.6-0.2;
- INFRARED: INTERSTELLAR: CONTINUUM;
- INFRARED: INTERSTELLAR: LINES