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تسجيل مستخدم جديدCharacterization of Dusty Debris Disks: the IRAS and Hipparcos Catalogs
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Dusty debris disks around main-sequence stars are signposts for the existence of planetesimals and exoplanets. From cross-correlating hip stars with the iras catalogs, we identify 146 stars within 120 pc of Earth that show excess emission at 60 $micron$. This search took special precautions to avoid false positives. Our sample is reasonably well distributed from late B to early K-type stars, but it contains very few later type stars. Even though iras flew more than 20 years ago and many astronomers have cross-correlated its catalogs with stellar catalogs, we were still able to newly identify debris disks at as many as 33 main-sequence stars; of these, 32 are within 100 pc of Earth. The power of an all-sky survey satellite like iras is evident when comparing our 33 new debris disks with the total of only 22 dusty debris disk stars detected first with the more sensitive, but pointed, satellite iso. Our investigation focuses on the mass, dimensions, and evolution of dusty debris disks.
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