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Chemical Evolution of the Magellanic Clouds : analytical models
| Content Provider | Semantic Scholar |
|---|---|
| Author | Pagel, Bernard E. J. Tautvaǐsienė, G. |
| Copyright Year | 1998 |
| Abstract | We have extended our analytical chemical evolution modelling ideas for the Galaxy (Pagel & Tautvaǐsienė 1995, 1997) to the Magellanic Clouds. Unlike previous authors (Russell & Dopita 1992; Tsujimoto et al. 1995; Pilyugin 1996), we assume neither a steepened IMF nor selective galactic winds, since among the α-particle elements only oxygen shows a large deficit relative to iron and a similar deficit is also found in Galactic supergiants. Thus we assume yields and time delays identical to those that we previously assumed for the solar neighbourhood. We include inflow and nonselective galactic winds and consider both smooth and bursting star formation rates, the latter giving a better fit to the age-metallicity relations. We predict essentially solar abundance ratios for primary elements and these seem to fit most of the data within their substantial scatter. Our LMC model also gives a remarkably good fit to the anomalous Galactic halo stars discovered by Nissen & Schuster (1997). Our models predict current ratios of SNIa to core-collapse supernova rates enhanced by 50 per cent and 25 per cent respectively relative to the solar neighbourhood, in fair agreement with ratios found by Cappellaro et al. (1993) for Sdm-Im relative to Sbc galaxies, but these ratios are sensitive to detailed assumptions about the bursts and a still higher enhancement in the LMC has been deduced from X-ray studies of remnants by Hughes et al. (1995). The corresponding ratios integrated over time up to the present are slightly below 1, but they exceed 1 if one compares the Clouds with the Galaxy at times when it had the corresponding metallicities. |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://arxiv.org/pdf/astro-ph/9801221v1.pdf |
| Language | English |
| Access Restriction | Open |
| Subject Keyword | Assumed Biological Evolution CCL16 gene Environmental Wind GUCY2C protein, human IBM SSEC Little man computer Magellanic Catalogue of Stars Oxygen Stars, Celestial |
| Content Type | Text |
| Resource Type | Article |
