The Dust Cloud around the White Dwarf G29-38

  title={The Dust Cloud around the White Dwarf G29-38},
  author={William T. Reach and Marc J. Kuchner and Ted von Hippel and Adam S. Burrows and Fergal Robert Mullally and Mukremin Kilic and Don E. Winget},
  journal={The Astrophysical Journal Letters},
  pages={L161 - L164}
We present new observations of the white dwarf G29-38 with the camera (4.5 and 8 μm), photometer (24 μm), and spectrograph (5.5-14 μm) of the Spitzer Space Telescope. This star has an exceptionally large infrared excess, amounting to 3% of the bolometric luminosity. The spectral energy distribution (SED) has a continuum peak around 4.5 μm and a 9-11 μm emission feature 1.25 times brighter than the continuum. A mixture of amorphous olivine and a small amount of forsterite in an emitting region 1… 
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