| Description |
We propose to acquire complete spectral-scans of the four most luminous and massive young stellar objects (MYSOs) in the giant W43 giant HII region complex located at a distance of 5.5 kpc in the Galactic Molecular Ring. The SED modes of the PACS spectrometer and the high-resolution mode of the SPIRE FTS will be used to trace variations in chemical abundances, excitation conditions, and structure in the SEDs as functions of the evolutionary states of these four massive objects. While the central pixels record the spectra of the target MYSOs, the adjacent pixels will probe the spectral properties of the surrounding dense molecular clumps, additional massive YSOs that happen to fall within the aperture, PDRs, and adjacent ionized regions. W43 is one of the most luminous star forming regions in the Galaxy. It has undergone a .mini-starburst. within the last few Myr. Massive star formation continues in at least 50 clumps spread over a 20 pc diameter region. The proposed observations will test evolutionary models for MYSOs. |
