|
Description
We present results from a 2.2{mu}m (limiting K about 14.5mag) survey of the northern portion of the Orion A molecular cloud. A total of 3548 sources were detected in the 1472arcmin^2^ area surveyed. We detect clustering of 2.2{mu}m sources at the locations of the Trapezium and OMC-2. No strict boundaries for these clusters could be drawn from our data because we find that the entire region surveyed shows an overabundance of sources when compared with background field levels. We find that the form of the observed K luminosity function (KLF) of stars near the Trapezium is consistent with that predicted from a Miller and Scalo (ApJS 41, 513 (1979) IMF, if the age of the cluster is about 1Myr. Away from the Trapezium and the OMC-2, the KLF of stars suggests that either this population contains more low mass stars or that it is older than the Trapezium stars. The survey was carried out using the Ohio State InfraRed Imaging System (OSIRIS) 256x256 HgCdTe array on the Perkins 1.8m telescope in November 1992. In survey mode OSIRIS provides a spatial resolution of 1.50arcsec/pixel; the total field of view of the camera is 6.4arcmin. The telescope was rastered on 4.2arcmin steps to produce a mosaic approximately 39x39arcmin, centered near the Trapezium. A total of 81 K-band images were obtained, each with an exposure time about 3s.
|
