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arXiv · 1005.3308

First detection of a low-mass stellar halo around the young open cluster Eta Chamaeleontis

Simon J. Murphy·Warrick A. Lawson·Michael S. Bessell
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Abstract

We have identified several lithium-rich low-mass (0.08<M<0.3 Msun) stars within 5.5 deg of the young open cluster Eta Chamaeleontis, nearly four times the radius of previous search efforts. Of these stars we propose 4 new probable cluster members, and 3 possible members requiring further investigation. These findings are consistent with a dynamical origin for the current configuration of the cluster, without the need to invoke an abnormal Initial Mass Function deficient in low-mass objects. Candidates were selected on the basis of DENIS and 2MASS photometry, NOMAD astrometry and extensive follow-up spectroscopy.

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Simon J. Murphy, Warrick A. Lawson, Michael S. Bessell. 2010-05-18. First detection of a low-mass stellar halo around the young open cluster Eta Chamaeleontis. https://doi.org/10.1111/j.1745-3933.2010.00879.x

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