A SURVEY OF DUST FEATURES IN THE 3 MICRON SPECTRA OF YSO CANDIDATES

We present the results of spectrophotometry from 1.3 to 4.2 mu m of 45 IRAS sources in the list of Campbell, Persson, & Matthews that have b een presumed to be luminous young stellar objects because of their inf rared colors and large IRAS fluxes. About 70% of the objects show 3.1 mu m H2O ice absorption or 3.3 mu m unidentified infrared emission, or both. Among those with 3.1 mu m H2O ice absorption, three objects see m to have a distinct absorption near 3.4 mu m, and their absorption pr ofiles are different than the optical depth profiles of young stellar objects in the literature. In the HKL two-color diagram, objects with ice absorption occupy the same region as previously known young stella r objects with the ice feature, and those with unidentified infrared e mission overlap with Herbig Ae/Be stars. We interpret the distribution in the HKL two-color diagram as indicating the evolutionary sequence of intermediate- to high-mass young stars.