SIMBAD references

We present an optical and near-infrared study of a 45'x45' field in NGC 2264, which includes both S Mon and the Cone Nebula. We report photometry at optical (UBVR_CI_C) and near-infrared (JHK) wavelengths for ∼5600 stars and spectroscopic classifications for ∼400 of these stars. We identify circumstellar disk candidates using three techniques: excess ultraviolet (U-V) emission, excess near-IR (I-K and H-K) emission, and Hα emission-line equivalent widths for those stars with spectra. We find generally good correlation between disk indicators thought to originate from different physical processes. We find little if any evolution of disk fraction with stellar age or mass. However, when we derive mass accretion rates (M{dot}) from the excess emission at U, we find that M{dot} decreases with age over the age range spanned by our data, ∼0.1-5 Myr, and increases with mass over the range ∼0.25-1 M_☉. These findings are comparable to results found previously by us in the Orion Nebula cluster flanking fields.