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Spectral energy distributions of quasars selected in the mid-infrared

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 نشر من قبل Mark Lacy
 تاريخ النشر 2012
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Mark Lacy




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We present preliminary results on fitting of SEDs to 142 z>1 quasars selected in the mid-infrared. Our quasar selection finds objects ranging in extinction from highly obscured, type-2 quasars, through more lightly reddened type-1 quasars and normal type-1s. We find a weak tendency for the objects with the highest far-infrared emission to be obscured quasars, but no bulk systematic offset between the far-infrared properties of dusty and normal quasars as might be expected in the most naive evolutionary schemes. The hosts of the type-2 quasars have stellar masses comparable to those of radio galaxies at similar redshifts. Many of the type-1s, and possibly one of the type-2s require a very hot dust component in addition to the normal torus emission.



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