Diffuse Ionized Gas inside the dwarf irregular galaxy NGC 6822
arXiv:astro-ph/0703082 · doi:10.1086/511267
Abstract
We have studied the differences between the diffuse ionized gas (DIG) and the HII regions along a slit position in the local dwarf irregular galaxy NGC 6822. The slit position passes through the two most prominent HII regions: Hubble V and Hubble X. Important differences have been found in the excitation, ionization, and [NII]6584/Ha and [SII]6717/Ha line ratios between the DIG and the HII locations. Moreover, the values of all the line ratios are not similar to those in the DIG locations of spiral galaxies but are very similar to the values in other irregular galaxies, such as IC 10. We also determined the rate of recombination using the HeI5875 line. Finally, we obtained a picture of the ionization sources of the DIG. We consider that the leakage of photons from the HII regions might explain most of the line ratios, except [NII]/Ha, which might be explained by turbulence.
27 pages, 9 figures, 1 table. AJ, in press
References in corpus (16)
- Star Formation Properties of a Large Sample of Irregular Galaxies
- The Local Group and other neighboring galaxy groups
- Evidence for an Additional Heat Source in the Warm Ionized Medium of Galaxies
- Further Spectroscopy of the Diffuse Ionized Gas in NGC 891 and Evidence for a Secondary Source of Ionization
- Evidence for tidal interaction and a supergiant HI shell in the Local Group dwarf galaxy NGC 6822
- Chemical Composition of Two H II Regions in NGC 6822 Based on VLT Spectroscopy
- Monte Carlo Photoionization Simulations of Diffuse Ionized Gas
- Spectrophotometry of HII Regions, Diffuse Ionized Gas and Supernova Remnants in M31: The Transition from Photo- to Shock-Ionization
- Photoionization Models of NGC 346
- The Star Formation History of NGC 6822
- Extraplanar Emission-Line Gas in Edge-On Spiral Galaxies. II. Optical Spectroscopy
- Emission Line Ratios and Variations in Temperature and Ionization State in the Diffuse Ionized Gas of Five Edge-on Galaxies
- Searching for additional heating - [OII] emission in the diffuse ionized gas of NGC891, NGC4631 and NGC3079
- Physical Conditions in the Dwarf Local Group Irregular Galaxy IC10. I- Diffuse Ionized Gas
- Diffuse Ionized Gas in irregular galaxies:I- GR 8 and ESO 245-G05
- Constraining the extra heating of the Diffuse Ionized Gas in the Milky Way