Abstract
Planetary nebulae (and in general any photoionized region) can be classified as ionization-bounded or density-bounded. It is important to determine in which case is the planetary nebula studied to be able to estimate from nebular observations, for example, the total rate of ionizing photons produced by the central star. In this paper we present a simple observational criterion that uses radio continuum images and allows to establish a necessary (but not suficient) condition for the planetary nebula to be considered as ionization-bounded. We apply the criterion to two planetary nebulae: NGC 7027 is most possibly ionization-bounded, while Hb 4 is density-bounded, at least in some directions.
| Original language | English |
|---|---|
| Pages (from-to) | 85-89 |
| Number of pages | 4 |
| Journal | Revista Mexicana de Astronomia y Astrofisica |
| Volume | 45 |
| Issue number | 1 |
| Publication status | Published - Apr 2009 |
Keywords
- Image processing
- Individual (NGC 7027, Hb 4)
- Planetary nebulae
- Techniques