A 2.2 m imaging survey of the Orion A molecular cloud Academic Article uri icon

abstract

  • We present results from a 2.2 m (Klimiting14.5 mag) survey of the northern portion of the Orion A molecular cloud. A total of 3548 sources were detected in the 1472 arcmin2 area surveyed. We detect clustering of 2.2 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 & Scalo [ApJS, 41, 513 (1979)] IMF, if the age of the cluster is 106 yr. 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. We have investigated how KLFs evolve with the age of a cluster, extinction, and excess emission from young stars by modeling KLFs of hypothetical clusters. Our results suggest that best fit slopes to the cumulative KLF provide a very crude method for characterizing KLFs, that age produces significant changes in the KLFs, and that turnovers in the observed KLF of young clusters do not conclusively demonstrate a "missing" low mass population.

published proceedings

  • Astronomical Journal

author list (cited authors)

  • Ali, B., & Depoy, D. L.

complete list of authors

  • Ali, B||Depoy, DL

publication date

  • February 1995