NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-06-15 T21:09:30 PDT
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For refcode 2006ApJ...653L..13S:
Retrieve 33 NED objects in this reference.
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NED Abstract

Copyright by American Astronomical Society. Reproduced by permission
2006ApJ...653L..13S Mid-Infrared Diagnostics of LINERs E. Sturm, D. Rupke, A. Contursi, D.-C. Kim, D. Lutz, H. Netzer, S. Veilleux, R. Genzel, M. Lehnert, L. J. Tacconi, D. Maoz, J. Mazzarella, S. Lord, D. Sanders, and A. Sternberg Abstract. We report results from the first mid-infrared spectroscopic study of a comprehensive sample of 33 LINERs, observed with the Spitzer Space Telescope. We compare the properties of two different LINER populations: infrared-faint LINERs, with LINER emission arising mostly in compact nuclear regions, and infrared-luminous LINERs, which often show spatially extended (non-AGN) LINER emission. We show that these two populations can be easily distinguished by their mid-infrared spectra in three different ways: (1) their mid-IR spectral energy distributions (SEDs), (2) the emission features of polycyclic aromatic hydrocarbons (PAHs), and (3) various combinations of IR fine-structure line ratios. IR-luminous LINERs show mid-IR SEDs typical of starburst galaxies, while the mid-IR SEDs of IR-faint LINERs are much bluer. PAH flux ratios are significantly different in the two groups. Fine-structure emission lines from highly excited gas, such as [O IV], are detected in both populations, suggesting the presence of an additional AGN in a large fraction of IR-bright LINERs as well, which contributes little to the combined mid-IR light. The two LINER groups occupy different regions of mid-infrared emission-line excitation diagrams. The positions of the various LINER types in our diagnostic diagrams provide important clues regarding the power source of each LINER type. Most of these mid-infrared diagnostics can be applied at low spectral resolution, making AGN- and starburst-excited LINERs distinguishable at high redshifts as well. Key words: Galaxies: Active, Infrared: Galaxies
Retrieve 33 NED objects in this reference.
Please click here for ADS abstract

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