Dust in the wind: Crystalline silicates, corundum, and periclase in PG 2112+059

  title={Dust in the wind: Crystalline silicates, corundum, and periclase in PG 2112+059},
  author={F. Markwick-Kemper and S. C. Gallagher and Dean C. Hines and Jeroen Bouwman},
  journal={The Astrophysical Journal},
We have determined the mineralogical composition of dust in the broad absorption line (BAL) quasar PG 2112+059 using mid-infrared spectroscopy obtained with the Spitzer Space Telescope. From spectral fitting of the solid state features, we find evidence for Mg-rich amorphous silicates with olivine stoichiometry, as well as the first detection of corundum (Al 2O3) and periclase (MgO) in quasars. This mixed composition provides the first direct evidence for a clumpy density structure of the grain… 

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