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arXiv · 0806.4465

The Chemical Enrichment History of the Small Magellanic Cloud and Its Gradients

Ricardo Carrera·Carme Gallart·Antonio Aparicio·Edgardo Costa·Rene A. Méndez·Noelia E. D. Noël
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Abstract

We present stellar metallicities derived from Ca II triplet spectroscopy in over 350 red giant branch stars in 13 fields distributed in different positions in the SMC, ranging from $\sim$1\arcdeg\@ to $\sim$4\arcdeg\@ from its center. In the innermost fields the average metallicity is [Fe/H] $\sim -1$. This value decreases when we move away towards outermost regions. This is the first detection of a metallicity gradient in this galaxy. We show that the metallicity gradient is related to an age gradient, in the sense that more metal-rich stars, which are also younger, are concentrated in the central regions of the galaxy.

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Ricardo Carrera, Carme Gallart, Antonio Aparicio, Edgardo Costa, Rene A. Méndez, Noelia E. D. Noël. 2008-06-27. The Chemical Enrichment History of the Small Magellanic Cloud and Its Gradients. https://doi.org/10.1088/0004-6256%2F136%2F3%2F1039

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