A near-infrared survey of the taurus molecular cloud: Near-infrared luminosity function

We have carried out a near-infrared survey of the central 1 degrees x 1 degrees region of Heiles cloud 2 (HC2), one of the densest regions of the Taurus molecular cloud. The limiting magnitude of this survey was 13.4 mag, and we have detected 831 sources at K. Based on the color-color diagram, 47 sources were classified as class II objects, and three as class I objects. The differential luminosity function of the class II objects in HC2 does not appear to have any cutoff, in agreement with the result by Comeron et al. for the rho Ophiuchi cloud. The majority of the sources are low-luminosity class II objects. Either these are very low mass class II objects with about 1/10 solar mass or the dissipation timescale of the circumstellar disk is longer than that of typical visible class II objects.