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arXiv · 1210.1894

Probing the M-sigma Relation in the Non-Local Universe Using Red QSOs

Gabriela Canalizo·Margrethe Wold·Kyle D. Hiner·Mariana Lazarova·Mark Lacy·Kevin Aylor
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Abstract

We describe a method to measure the M-sigma relation in the non-local universe using dust-obscured QSOs. We present results from a pilot sample of nine 2MASS red QSOs with redshifts 0.14 0.1 AGN (including our sample and those of previous studies) have significantly higher BH mass than those of local AGN, so a direct comparison is not straightforward. Further, using several samples of local and higher-z AGN, we find a striking trend of an increasing offset with respect to the local M-sigma relation as a function of AGN luminosity, with virtually all objects with log(L_5100/erg s^-1) > 43.6 falling above the relation. Given the relatively small number of AGN at z>0.1 for which there are direct measurements of stellar velocity dispersions, it is impossible at present to determine whether there truly is evolution in M-sigma with redshift. Larger, carefully selected samples of AGN are necessary to disentangle the dependence of M-sigma on mass, luminosity, accretion rates, and redshift.

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Gabriela Canalizo, Margrethe Wold, Kyle D. Hiner, Mariana Lazarova, Mark Lacy, Kevin Aylor. 2012-10-05. Probing the M-sigma Relation in the Non-Local Universe Using Red QSOs. https://doi.org/10.1088/0004-637x%2F760%2F1%2F38

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