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

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 نشر من قبل Luigi Spinoglio
 تاريخ النشر 2008
  مجال البحث فيزياء
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The Spitzer high resolution spectra of 72 Seyfert galaxies from the 12$mu$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$mu$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 2s 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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