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

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.

5 Pages. 5 Figures and 1 Table. Accepted for publication in MNRAS Letters. Higher resolution figures available at http://www.mso.anu.edu.au/~murphysj/.

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