# Spitzer: Accretion in Low-Mass Stars and Brown Dwarfs in the λ Orionis Cluster

@article{Navascus2007SpitzerAI,
title={Spitzer: Accretion in Low-Mass Stars and Brown Dwarfs in the $\lambda$ Orionis Cluster},
author={David Barrado y Navascu{\'e}s and John R. Stauffer and M. Morales-Calder{\'o}n and Amelia Bayo and Giovanni Fazzio and Tom Megeath and Lori Allen and Lee Hartmann and Nuria Calvet},
journal={The Astrophysical Journal},
year={2007},
volume={664},
pages={481 - 500}
}
• Published 16 April 2007
• Physics
• The Astrophysical Journal
We present multiwavelength optical and IR photometry of 170 previously known low-mass stars and brown dwarfs of the 5 Myr Collinder 69 cluster (λ Orionis). The new photometry supports cluster membership for most of them, with less than 15% of the previous candidates identified as probable nonmembers. The near-IR photometry allows us to identify stars with IR excesses, and we find that the Class II population is very large, around 25% for stars (in the spectral range M0-M6.5) and 40% for brown…

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