A near-infrared imaging survey of the chamaeleon I dark cloud

We describe a near-infrared imaging survey covering similar to 1 deg(2) of the Chamaeleon I dark cloud. The survey is complete for K < 15.0, H < 16.0, and J < 16.5, roughly 2 magnitudes more sensitive than previous large-scale surveys. We use the large number of background stars detected to derive an accurate near-infrared extinction law for the cloud and select new candidate members with near-infrared color excesses. We list 100 candidates of the cloud with K greater than or equal to 12.0, based on their positions in the J-H, H-K color-color diagram. These new stars have low luminosities (K similar to 12-16, and H-K greater than or similar to 0.5-1.5) may have masses close to or even below the hydrogen-burning limit.