Tuesday, October 9, 2012

1210.1894 (Gabriela Canalizo et al.)

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

Gabriela Canalizo, Margrethe Wold, Kyle D. Hiner, Mariana Lazarova, Mark Lacy, Kevin Aylor
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 0.140.1 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.
View original: http://arxiv.org/abs/1210.1894

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