A Tidally Disrupted Asteroid around the White Dwarf G29-38
نویسندگان
چکیده
منابع مشابه
Keck Speckle Imaging of the White Dwarf G29-38: No Brown Dwarf Companion Detected
The white dwarf Giclas 29-38 has attracted much attention due to its large infrared excess and the suggestion that excess might be due to a companion brown dwarf. We observed this object using speckle interferometry at the Keck telescope, obtaining diffraction-limited resolution (55 milliarcseconds) at K band, and found it unresolved. Assuming the entire K band excess is due to a single point-l...
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We present new observations of the white dwarf G 29-38 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 has a continuum peak around 4.5 μm and a 9–11 μm emission feature 1.25 times brighter than the co...
متن کاملDiscovery of Photospheric Calcium Line-Strength Variations in the Dazd White Dwarf G29-38
Metals in the photospheres of white dwarfs with TeA between 12,000 and 25,000 K should gravitationally settle out of these atmospheres in 1Y2 weeks. Temporal variations in the line strengths of these metals could provide a direct measurement of episodic metal accretion. Using archival VLTand Keck spectroscopy, we find evidence that the DAZd white dwarf G29-38 shows significant changes in its Ca...
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Our new VLA 1 observation of M82 reveals a triangular central concentration of under cooperative agreement with the National Science Foundation. neutral atomic gas (1:9 10 8 M) and several > 10 kpc long tidal streamers originating from M82 itself. The coincidence of the beginning of the tidal streamer with the aring of the optical disk as well as the smooth continuation of the disk velocity eld...
متن کاملX-ray and Infrared Observations of Two Externally-polluted White Dwarfs
With XMM-Newton and the Spitzer Space Telescope, we obtain upper bounds to the X-ray fluxes from G29-38 and GD 362, and the 70 μm flux from G29-38. These data provide indirect evidence that G29-38 is accreting from a tidally disrupted asteroid: it is neither accreting large amounts of hydrogen and helium nor is its surrounding dusty disk being replenished from a reservoir of cold grains experie...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2003
ISSN: 0004-637X,1538-4357
DOI: 10.1086/374036