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تسجيل مستخدم جديدDebris discs around nearby Solar analogues
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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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