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تسجيل مستخدم جديدSeyfert Galaxies in the Local Universe: Analysis of Spitzer Spectra of a Complete Sample
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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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A complete flux-limited sample of 50 galaxies is presented having f_{ u}(24um) > 10mJy, chosen from a survey with the Multiband Imaging Photometer on Spitzer (MIPS) of 8.2 deg^{2} within the NOAO Deep Wide-Field Survey region in Bootes (NDWFS). Spect
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Results obtained from an X-ray spectral survey of nearby Seyfert galaxies using XMM--Newton are reported. The sample was optically selected, well defined, complete in B mag, and distance limited: it consists of the nearest (D<22 Mpc) 27 Seyfert galax
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