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The metallicity of circumnuclear star forming regions

A. I. Diaz·E. Terlevich·M. Castellanos·G. F. Hagele
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Abstract

We present a spectrophotometric study of circumnuclear star forming regions (CNSFR) in the early type spiral galaxies: NGC 2903, NGC 3351 and NGC 3504, all of them of over solar metallicity according to standard empirical calibrations. A detailed determination of their abundances is made after careful subtraction of the very prominent underlying stellar absorption. It is found that most regions show the highest abundances in HII region-like objects. The relative N/O and S/O abundances are discussed. In is also shown that CNSFR, as a class, segregate from the disk HII region family, clustering around smaller ``softness parameter" -- η' -- values, and therefore higher ionizing temperatures.

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A. I. Diaz, E. Terlevich, M. Castellanos, G. F. Hagele. 2006-10-26. The metallicity of circumnuclear star forming regions. https://arxiv.org/abs/astro-ph/0610787

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