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arXiv · 0907.3677

Debris discs around nearby Solar analogues

J. S. Greaves·M. C. Wyatt·G. Bryden
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Abstract

An unbiased search for debris discs around nearby Sun-like stars is reported. Thirteen G-dwarfs at 12-15 parsecs distance were searched at 850 $\umu$m wavelength, and a disc is confirmed around HD 30495. The estimated dust mass is 0.008 M$_{\oplus}$ with a net limit $\la 0.0025$ M$_{\oplus}$ for the average disc of the other stars. The results suggest there is not a large missed population of substantial cold discs around Sun-like stars -- HD 30495 is a bright rather than unusually cool disc, and may belong to a few hundred Myr-old population of greater dust luminosity. The far-infared and millimetre survey data for Sun-like stars are well fitted by either steady state or stirred models, provided that typical comet belts are comparable in size to that in the Solar System.

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J. S. Greaves, M. C. Wyatt, G. Bryden. 2009-07-21. Debris discs around nearby Solar analogues. https://doi.org/10.1111/j.1365-2966.2009.15048.x

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