Projects per year
Abstract
The diffuse ionized gas (DIG) in galaxies traces photoionization feedback from massive stars. Through three-dimensional photoionization simulations, we study the propagation of ionizing photons, photoionization heating and the resulting distribution of ionized and neutral gas within snapshots of magnetohydrodynamic simulations of a supernova-driven turbulent interstellar medium. We also investigate the impact of non-photoionization heating on observed optical emission line ratios. Inclusion of a heating term which scales less steeply with electron density than photoionization is required to produce diagnostic emission line ratios similar to those observed with the Wisconsin H alpha Mapper. Once such heating terms have been included, we are also able to produce temperatures similar to those inferred from observations of the DIG, with temperatures increasing to above 15 000 K at heights |z| ≳ 1 kpc. We find that ionizing photons travel through low-density regions close to the mid-plane of the simulations, while travelling through diffuse low-density regions at large heights. The majority of photons travel small distances (≲ 100 pc); however some travel kiloparsecs and ionize the DIG.
Original language | English |
---|---|
Pages (from-to) | 3027-3035 |
Number of pages | 9 |
Journal | Monthly Notices of the Royal Astronomical Society |
Volume | 440 |
Issue number | 4 |
Early online date | 17 Apr 2014 |
DOIs | |
Publication status | Published - 1 Jun 2014 |
Keywords
- ISM: General
- galaxies: ISM
- Diffuse ionized-gas
- H-II regions
- B-type stars
- Spiral galaxies
- Vertical structure
- Dwarf galaxies
- Galactic disc
- Inner galaxy
- Milky-way
- Ionization
Fingerprint
Dive into the research topics of 'Photoionization and heating of a supernova-driven turbulent interstellar medium'. Together they form a unique fingerprint.Projects
- 2 Finished
-
Astrophysics at St Andrews:2012 - 2014: Astrophysics at St Andrews: 2012 - 2014
Horne, K. D. (PI)
Science & Technology Facilities Council
1/10/11 → 31/03/12
Project: Standard
-
Wide Area Search for Planets: Project support for the Wide Area Search for Planets
Cameron, A. C. (PI)
Science & Technology Facilities Council
1/08/08 → 31/07/11
Project: Standard