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تسجيل مستخدم جديدEvidence for Early Circumstellar Disk Evolution in NGC 2068/71
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K.M. Flaherty
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We study the disk and accretion properties of young stars in the NGC 2068 and NGC 2071 clusters. Using low-resolution optical spectra, we define a membership sample and determine an age for the region of ~2 Myr. Using high-resolution spectra of the H-alpha line we study the accretion activity of these likely members and also examine the disk properties of the likely members using IRAC and MIPS mid-infrared photometry. A substantial fraction (79%) of the 67 members have an infrared excess while all of the stars with significant infrared excess show evidence for active accretion. We find three populations of evolved disks (IRAC-weak, MIPS-weak and transition disks) all of which show decreased accretion activity in addition to the evidence for evolution in the dust disk.
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