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ECHA J0843.3-7905: Discovery of an 'old' classical T Tauri star in the eta Chamaeleontis cluster

Warrick A. Lawson·Lisa A. Crause·Eric E. Mamajek·Eric D. Feigelson
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Abstract

A limited-area survey of the eta 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 approx 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_sun) primary known in the cluster.

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Warrick A. Lawson, Lisa A. Crause, Eric E. Mamajek, Eric D. Feigelson. 2001-12-13. ECHA J0843.3-7905: Discovery of an 'old' classical T Tauri star in the eta Chamaeleontis cluster. https://doi.org/10.1046/j.1365-8711.2002.05093.x

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