# Membership, binarity and accretion among very low-mass stars and brown dwarfs of the σ Orionis cluster

@article{Kenyon2005MembershipBA,
title={Membership, binarity and accretion among very low-mass stars and brown dwarfs of the $\sigma$ Orionis cluster},
author={M. Kenyon and R. Jeffries and T. Naylor and J. Oliveira and P. Maxted},
journal={Monthly Notices of the Royal Astronomical Society},
year={2005},
volume={356},
pages={89-106}
}
• M. Kenyon, +2 authors P. Maxted
• Published 2005
• Physics
• Monthly Notices of the Royal Astronomical Society
Intermediate-resolution (R∼ 7000) spectroscopy is presented for 76 photometrically selected very low-mass (0.04 < M < 0.3 M⊙) candidate members of the young cluster around σ Orionis (σ Ori). More than two-thirds appear to be genuine cluster members on the basis that they exhibit Li i 6708-A absorption, weak Na i 8183/8195 A features and a radial velocity consistent with the cluster mean. Photometric selection alone therefore appears to be very effective in identifying cluster members in this… Expand
73 Citations
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