This award supports Dr. Sutton's program in interstellar spectroscopy at submillimeter wavelenghts. Part of the work is instrumental. An existing 345 GHz receiver system will be modified to operate at 500 GHz and, ultimately, other submillimeter bands. This receiver system will then be used for an observational program which emphasizes studies of galactic structure, regions of star formation, and interstellar chemistry. In addition, further analysis and interpretation will be carried out for several ongoing projects based on data obtained at 345 GHz. Submillimeter observations can provide unique information about the interstellar medium, information not available at millimeter or other wavelengths. High frequency spectral lines sample denser, higher excitation regions, making them vital probes of molecular cloud cores. Previously submillimeter observations had been limited by a lack of suitable telescopes and receiver systems. A number of high quality submillimeter telescopes have become available in the past few years, placing greater emphasis on the need for sensitive receiver systems such as the one to be developed by Dr. Sutton.
