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Elemental Abundances in NGC 3516

T. J. Turner·S. B. Kraemer·R. F. Mushotzky·I. M. George·J. R. Gabel
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Abstract

We present RGS data from an XMM-Newton observation of the Seyfert 1 galaxy NGC 3516, taken while the continuum source was in an extreme low state. The spectrum shows numerous emission lines including the H-like lines of C, N and O and the He-like lines of N, O and Ne. These data show that the N lines are far stronger than would be expected from gas of solar abundances. Based on our photoionization models, we find that N is overabundant compared to C, O and Ne by at least a factor of 2.5. We suggest this is the result of secondary production of N in intermediate mass stars, and indicative of the history of star formation in NGC 3516.

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T. J. Turner, S. B. Kraemer, R. F. Mushotzky, I. M. George, J. R. Gabel. 2003-05-15. Elemental Abundances in NGC 3516. https://doi.org/10.1086/376901

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