Adaptive Optics Imaging of the Orion Trapezium Cluster

M. Simon, L. M. Close, Tracy L. Beck
1999 Astronomical Journal  
We have imaged an area D5 arcmin2 at the center of the Trapezium cluster in Orion in the K band using the University of Hawaii (UH) adaptive optics system at the UH 2.2 m telescope. Our survey detects 292 stars brighter than K \ 18.2 mag and resolves pairs to the di †raction limit of the tele-0A .23 scope. The binary fraction in the angular separation range corresponding to 132È264 AU at 440 0A .3È0A .6, pc, is indistinguishable from that of the solar-like stars in the solar neighborhood.
more » ... neighborhood. Proplyds are associated with both single stars and visual binaries. About half the stars in our sample have also been measured at V and I by Prosser et al. ; most of these seem to be about 106 yr old, observed through moderate extinction, and having some excess emission at K. The luminosity function turns over before the stellar limit of D13.5 mag, indicating that the cluster does not contain a large population of massive brown dwarfs.
doi:10.1086/300767 fatcat:rm4ajpv4xnelfkil6566muppvi