AST-9615839 ABSTRACT: J. Lutz This research project will involve the investigations of the connections between Asymptotic Giant Branch (AGB) stars, Post-AGB objects and Planetary Nebulae (PN) by using PN morphologies as a focus for the work. Recent observational studies indicate that the structures observed in PN shells seem to originate earlier in the star's history than was suspected previously. Consequently, a careful review of the phenomena manifested by stars in the evolutionary stages prior to the PN (i.e., AGB stars and Post-AGB objects) will be conducted to elucidate the shaping mechanisms (possibilities include binary star interactions, pulsations, winds in single stars, disks) for PN shells. The research project has several phases. It begins with an investigation of the literature on AGB stars and Post-AGB objects. Additional information will be gained by attending two specialized meetings (June and July 1997) which deal with current research on Stellar Pulsations and Cool Stars. The observing phase of the research will begin in September 1997. Based on the knowledge gained in the first phase of the research, optical and infrared observations will be obtained with the goal of elucidating how structures emerge in PN shells. The results from the research project will be published and presentations at professional meetings will be given. These research activities are being carried out under the NSF Career Advancement Awards (CAA) program. The research will be done while working in the Astronomy Department at the University of Washington with collaborators Bruce Balick and George Wallerstein, who are experts in PN and AGB stars respectively. The Principal Investigator will be on sabbatical leave from the Washington State University during the period of the award and thus will be able to do research full time.
