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arXiv · 0807.4896

Seyfert Galaxies in the Local Universe: Analysis of Spitzer Spectra of a Complete Sample

S. Tommasin·L. Spinoglio·K. Hainline·M. A. Malkan·H. Smith
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Abstract

The Spitzer high resolution spectra of 72 Seyfert galaxies from the 12$μ$m Galaxy Sample are presented and discussed. The presence of starburst components in these galaxies can be quantified by powerful mid-IR diagnostics tools (i.e. 11.25$μ$m PAH feature equivalent width and the H$_2$ emission line intensity), as well as the AGN dominance can be measured by specific fine structure line ratios (e.g. [NeV]/[NeII], [NeV]/[SiII], etc.). The two types of Seyfert galaxies do not show any statistical difference in our diagnostic tools. However, the Seyfert 2's showing hidden Broad Line Regions in spectro-polarimetric observations have on average an higher AGN dominance, a weaker star formation component and a warmer [60 - 25] spectral index than those without broad emission lines.

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S. Tommasin, L. Spinoglio, K. Hainline, M. A. Malkan, H. Smith. 2008-07-30. Seyfert Galaxies in the Local Universe: Analysis of Spitzer Spectra of a Complete Sample. https://arxiv.org/abs/0807.4896

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