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arXiv · 1010.6218

The Absence of Cold Dust and the Mineralogy and Origin of the Warm Dust Encircling BD +20 307

A. J. Weinberger·E. E. Becklin·I. Song·B. Zuckerman
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Abstract

Spitzer Space Telescope photometry and spectroscopy of BD +20 307 show that all of the dust around this remarkable Gyr-old spectroscopic binary arises within 1 AU. No additional cold dust is needed to fit the infrared excess. Peaks in the 10 and 20 micron spectrum are well fit with small silicates that should be removed on a timescale of years from the system. This is the dustiest star known for its age, which is >1 Gyr. The dust cannot arise from a steady-state collisional cascade. A catastrophic collision of two rocky, planetary-scale bodies in the terrestrial zone is the most likely source for this warm dust because it does not require a reservoir of planetesimals in the outer system.

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A. J. Weinberger, E. E. Becklin, I. Song, B. Zuckerman. 2010-10-29. The Absence of Cold Dust and the Mineralogy and Origin of the Warm Dust Encircling BD +20 307. https://doi.org/10.1088/0004-637x%2F726%2F2%2F72

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