ECHA J0843.3–7905: Discovery of an ‘old’ classical T Tauri star in the η Chamaeleontis cluster
نویسندگان
چکیده
A limited-area survey of the η Chamaeleontis cluster has identified 2 new late-type members. The more significant of these is ECHA J0843.3–7905 (= IRAS F08450– 7854), a slowly-rotating (P = 12 d) M2 classical T Tauri (CTT) star with a spectrum dominated by Balmer emission. At a distance of 97 pc and cluster age of ≈ 9 Myr, the star is a nearby rare example of an ‘old’ CTT star and promises to be a rewarding laboratory for the study of disk structure and evolution in pre-main sequence (PMS) stars. The other new member is the M4 weak-lined T Tauri (WTT) star ECHA J0841.5–7853, which is the lowest mass (M ≈ 0.2 M⊙) primary known in the cluster.
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