Spitzer Observations of GD 362 and Other Metal - Rich
نویسندگان
چکیده
A Spitzer IRAC survey of 17 nearby metal-rich white dwarfs, nominally DAZ stars, reveals excess emission from only 3 targets: G29-38, GD 362 and G167-8. Observations of GD 362 with all three Spitzer instruments reveals a warm (≈ 1000 K) dust continuum, very strong silicate emission, and the likely presence of cooler (≈ 500 K) dust. While there is a general similarity between the mid-infrared spectral energy distributions of G29-38 and GD 362, the IRAC fluxes of G167-8 are so far unique among white dwarfs. However, further observations of G167-8 are required before the measured excess can be definitely associated with the white dwarf.
منابع مشابه
Spitzer Irac Observations of White Dwarfs. I. Warm Dust at Metal-rich Degenerates
This paper presents the results of a Spitzer IRAC 3−8 μm photometric search for warm dust orbiting 17 nearby, metal-rich white dwarfs, 15 of which apparently have hydrogen dominated atmospheres (type DAZ). G166-58, G29-38, and GD 362 manifest excess emission in their IRAC fluxes and the latter two are known to harbor dust grains warm enough to radiate detectable emission at near-infrared wavele...
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