Evolution of Dusty Disks in Nearby Young Stellar Groups
نویسنده
چکیده
Given their proximity and age differences, nearby groups of young stars are valuable laboratories for investigations of disk evolution and diversity. The estimated 10-Myr age of groups like the TW Hydrae Association provides a strong constraint on disk evolution timescales and fills a significant gap in the age sequence between 1-Myr-old T Tauri stars in molecular clouds and 50-Myr-old nearby open clusters. I review the results of recent and on-going studies of dusty disks in three nearby groups –TW Hya, η Cha and MBM 12– that suggest rapid evolution of inner disks. However, it is unlikely that there is a universal evolutionary timescale for protoplanetary disks, especially when the influence of companion stars is taken into account.
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