Properties of the monoceros R2 stellar cluster

We present an extensive study of the stellar population of an embedded cluster in the MonR2 molecular cloud based upon a wide field (similar to 15'x15') J, H, and K band mosaic, deep near-infrared imaging at J, H, KI and nbL' bands of the central cluster region, and spectroscopic observations of 34 stars. By comparing the properties of the MonR2 cluster with other star forming regions, we ultimately hope to lean how the properties and formation of stars of various masses are related to the local physical conditions. The K band star counts indicate that the MonR2 cluster extends over a similar to 1.1 pc X 2.1 pc area with a FWPM cluster size of similar to 0.38 pc. Within this region the cluster contains similar to 309 stars brighter than m(k) = 14.5(m) and greater than or equal to 475 stars over all magnitudes with a central stellar volume density of similar to 9000 stars pc(-3). We have further explored the properties of the cluster by using the spectroscopic and photometric data to construct an extinction-limited sample of 115 stars in the central 0.77 pc X 0.77 pc region of the cluster that is designed to contain all stars with A(v) less than or equal to 11.3(m) and stellar masses greater than or equal to 0.1 M. As a lower limit, 62% of the stars in this sample contain a near-infrared excess at K and/or L band. The K band excess fraction may be as high as 72% if the accretion characteristics of the stars in the MonR2 cluster are similar to stars in Taurus-Auriga. An initial reconnaissance of the stellar mass function suggests that the ratio of high to low moss stars in the extinction-limited sample is consistent with the value expected for a Miller-Scale IMF. We do not find compelling evidence for mass segregation in the extinction-limited sample for stellar masses less than or equal to 2 M., although the most massive star(similar to 10 M.) in the cluster appears to be forming near the cluster center. The properties of the MonR2 cluster are similar to other rich young clusters in the solar neighborhood, such as NGC 2024 and the Trapezium. (C) 1997 American Astronomical Society.