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arXiv · 1011.4593

Low Luminosity AGN candidates in SDSS

J. P. Torres-Papaqui·R. Coziol·J. M. Islas-Islas·R. A. Ortega-Minakata·D. M. Neri-Larios
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Abstract

In a sample of 476931 NELGs obtained from the SDSS DR5 data we find that in 22% of the galaxies the emission line [OIII]$λ$5007, H$β$, or both, are missing. The nature of the activity in these galaxies was determined using a diagnostic diagram comparing the equivalent width of [NII]$λ$6584 with the ratio [NII]$λ$6584/H$α$. The majority of these galaxies are AGN. The H$α$ emission lines have a mean FWHM of 400 km s$^{-1}$ and mean luminosity of 5.6$\times$10$^{39}$ erg s$^{-1}$, which justify their classification as LLAGN. A study of their star formation histories using STARLIGHT reveals no trace of star formation over the last Gyr period. The hosts of the LLAGNs are early-type, T$\le 2$, with bulges more massive than those of the luminous AGNs.

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J. P. Torres-Papaqui, R. Coziol, J. M. Islas-Islas, R. A. Ortega-Minakata, D. M. Neri-Larios. 2010-11-20. Low Luminosity AGN candidates in SDSS. https://arxiv.org/abs/1011.4593

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