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Determinations of siii, oiv and nev abundances in planetary nebulae from ir lines
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Shure, M. A. McCarthy, J. F. Houck, J. R. Gull, G. E. Forrest, W. J. Briotta Jr., D. A. Herter, T. |
| Copyright Year | 1983 |
| Description | Airborne observations of the infrared forbidden lines (SIII) 18.71 microns, (NeV) 24.28 microns and (OIV) 25.87 microns were made for twelve planetary nebulae. One or more of the lines was detected in seven of these nebulae and ionic abundances were calculated. These results are insensitive to nebula temperatures, in contrast to the case for optical or UV lines. However, density estimates from optical and UV forbidden lines were required to obtain abundances. The NeV infrared line flux from NGC 7662 was combined with the 3426A flux to obtain a NeV electron temperature of 11,200 (+2000, - 1100) K, which overlaps OIII temperature measurements. Since the ionization potential of NeIV is much greater than that of OII, T sub e (NeV) would be expected to be much greater than T sub e (OIII). In fact, numerical models predict T sub e (NeV) (16-20) x 1000 K. This discrepancy may indicate inaccuracies in currently available atomic parameters for NeV. |
| File Size | 11295539 |
| Page Count | 40 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19830011391 |
| Archival Resource Key | ark:/13960/t0xq1tr9x |
| Language | English |
| Publisher Date | 1983-01-01 |
| Access Restriction | Open |
| Subject Keyword | Astronomy Oxygen C-141 Aircraft Ions Abundance Planetary Nebulae Composition Property Infrared Astronomy Infrared Spectra Forbidden Transitions Neon Line Spectra Electron Energy Sulfur Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
