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arXiv · 1412.7039

Mining for Dust in Type 1 Quasars

Coleman M. Krawczyk·Gordon T. Richards·S. C. Gallagher·Karen M. Leighly·Paul C. Hewett·Nicholas P. Ross·P. B. Hall
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Abstract

We explore the extinction/reddening of ~35,000 uniformly selected quasars with 0 0.1 and 0.1% (1.3%) with E(B-V)>0.2. Simulations show both populations of quasars are intrinsically bluer than the mean composite, with a mean spectral index ($α_λ$) of -1.79 (-1.83). The emission and absorption-line properties of both samples reveal that quasars with intrinsically red continua have narrower Balmer lines and stronger ionizing spectral lines, the latter indicating a harder continuum in the extreme-UV and the former pointing to differences in black hole mass and/or orientation.

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Coleman M. Krawczyk, Gordon T. Richards, S. C. Gallagher, Karen M. Leighly, Paul C. Hewett, Nicholas P. Ross, P. B. Hall. 2015-06-02. Mining for Dust in Type 1 Quasars. https://doi.org/10.1088/0004-6256%2F149%2F6%2F203

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