Can Post T Tauri Stars Be Found ? Yes !
نویسنده
چکیده
I review the observational challenges of finding post T Tauri stars (PTTS), defined here as low-mass, pre–main-sequence stars with ages of 107–108 yr. Such stars are difficult to find because they are less active than younger T Tauri stars, and they may not be associated with molecular gas. They are useful for studying the evolution of circumstellar disks and stellar activity between the 106-yr ages of nearby star-forming regions and the main sequence. However, care must be taken in the search process so that the selection criteria used to locate such stars do not bias the sample used for subsequent evolutionary studies.
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