Bieging, John AST 96-18523 Dr. Bieging will study the process of mass loss in evolved stars of intermediate mass, both red giant stars and stars evolving beyond to become planetary nebulae. His observational program takes advantage of a variety of techniques and instrumentation to obtain a full picture of the gas and dust in the circumstellar envelopes of these stars, with a particular focus on the source IRC+10216. The analysis of molecular spectroscopy in the mm-wavelengths will reveal details about the chemical and physical structure of the circumstellar envelope and the process of mass loss. Observations in the mid-IR for a sample of stars evolving from the red giant to the planetary nebulae stage will also allow the determination of the dust distribution, density, and temperature in the stellar envelopes. ***
