The Star Formation History of Leo I
| Autor: | C. Gallart, W. L. Freedman |
|---|---|
| Rok vydání: | 1999 |
| Předmět: |
Physics
Intergalactic star Star formation X-ray binary Astronomy Astrophysics::Cosmology and Extragalactic Astrophysics Astrophysics Star count Herbig Ae/Be star Physics::Space Physics Binary star Astrophysics::Solar and Stellar Astrophysics Astrophysics::Earth and Planetary Astrophysics Astrophysics::Galaxy Astrophysics |
| Zdroj: | Symposium - International Astronomical Union. 192:151-157 |
| ISSN: | 0074-1809 |
| Popis: | We advance some results of our study of the star formation history of the Local Group dSph galaxy Leo I, obtained through the analysis of its deep HST color-magnitude diagram (CMD) using model CMDs computed from stellar evolutionary models. We conclude that most star formation (≃ 90%) took place in Leo I between 7 and 1 Gyr ago. It seems to have started at a very low rate ≃ 15 Gyr ago and continued, also at a very low rate, from 1 Gyr ago until the present time. A constant Z=0.0004 and a large fraction of binary stars are required to obtain the best agreement with both the distribution of stars across the CMD and with its morphology. An IMF like the one obtained by Kroupa et al. (1993) for the solar neighborhood, or steeper, is compatible with the data. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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