Program: GS-2011A-Q-91

Current estimates of the impact of close binary stars on the shaping and ejection of planetary nebulae include a number of systems for which no published data exists other than discovery notations and orbital periods. Only ten of the currently catalogued 27 binary systems have been well studied. With the current emphasis in planetary nebula research on determining the role of binarity in the planetary nebula process, it is imperative that we understand as well aspossible the small number of detected binary systems. We have recently obtained orbit-resolved photometry of six of the poorly studied systems in order to confirm variability, determine orbital ephemerides, and make a preliminary attempt to classify the type of binary system. We propose here to obtain spectroscopy that will allow us to identify if each is a single or double-lined binary system, to determine radial velocity curves, and pair with the existing photometry to produce physical parameters for the binary systems. Orbit-resolved spectra will produce radial velocity curves which, paired with photometry and binary modeling programs can produce system masses, radii, and other important physical information.The result will be a better understanding of the role of binaries in the ejection and shaping of planetary nebulae.