Dust-to-gas ratio and star formation history of blue compact dwarf galaxies
| Autor: | Hiroyuki Hirashita, Y. Y. Tajiri, H. Kamaya |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2002 |
| Předmět: |
Physics
Star formation Metallicity Astrophysics (astro-ph) FOS: Physical sciences Astronomy and Astrophysics Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics Type (model theory) Chemical evolution Supernova Space and Planetary Science Astrophysics::Solar and Stellar Astrophysics Astrophysics::Earth and Planetary Astrophysics Astrophysics::Galaxy Astrophysics Dwarf galaxy |
| Popis: | This paper investigates the origin of the observed large variety in dust-to-gas ratio among blue compact dwarf galaxies (BCDs). By applying our chemical evolution model, we find that the dust destruction can largely suppress the dust-to-gas ratio when the metallicity of a BCD reaches $12+\log{\rm (O/H)}\sim 8$, i.e., a typical metallicity level of BCDs. We also show that dust-to-gas ratio is largely varied owing to the change of dust destruction efficiency that has two effects: (i) a significant contribution of Type Ia supernovae to total supernova rate; (ii) variation of gas mass contained in a star-forming region. While mass loss from BCDs was previously thought to be the major cause for the variance of dust-to-gas ratio, we suggest that the other two effects are also important. We finally discuss the intermittent star formation history, which naturally explains the large dispersion of dust-to-gas ratio among BCDs. 7 pages LaTeX, to appear in A&A |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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