2009ApJ...702L.128A

We report the detection of several molecular gas-phase and ice absorption features in three photometrically selected young stellar object (YSO) candidates in the central 280 pc of the Milky Way. Our spectra, obtained with the Infrared Spectrograph (IRS) onboard the Spitzer Space Telescope, reveal gas-phase absorption from CO₂(15.0 µm), C₂H₂(13.7 µm), and HCN (14.0 µm). We attribute this absorption to warm, dense gas in massive YSOs. We also detect strong and broad 15 µm CO₂ ice absorption features, with a remarkable double-peaked structure. The prominent long-wavelength peak is due to CH₃OH-rich ice grains, and is similar to those found in other known massive YSOs. Our IRS observations demonstrate the youth of these objects, and provide the first spectroscopic identification of massive YSOs in the Galactic Center.