The Spitzer c2d Survey of Large, Nearby, Interstellar Clouds. V. Chamaeleon II Observed with IRAC

Abstract

We present IRAC (3.6, 4.5, 5.8, and 8.0 micron) observations of the Chamaeleon II molecular cloud. The observed area covers about 1 square degree defined by $A_V >2$. Analysis of the data in the 2005 c2d catalogs reveals a small number of sources (40) with properties similar to those of young stellaror substellar objects (YSOs). The surface density of these YSO candidates is low, and contamination by background galaxies appears to be substantial, especially for sources classified as Class I or flat SED. We discuss this problem in some detail and conclude that very few of the candidate YSOs in early evolutionary stages are actually in the Cha II cloud. Using a refined set of criteria, we define a smaller, but more reliable, set of 24 YSO candidates.