PI: Todd Hillwig, Valparaiso University, email@example.com
Address: Physics Department, 1610 Campus Drive, Valparaiso, IN 46383, USA
CoI: David Frew, Macquarie University
CoI: Orsola De Marco, Macquarie University
CoI: Dimitri Douchin, Macquarie University
Title: Detecting Close Binary Central Stars of Planetary Nebulae: The Photometric Monitoring Campaign
Abstract: Our understanding of close binary stars with a compact companion has a broad impact on astrophysics. Since most such systems include a white dwarf, and all have gone through a common envelope phase, studying these systems in planetary nebulae provides a window to the beginning of this evolutionary stage. The sample of close binaries in planetary nebulae is approaching a statistically significant number. Past surveys have shown the fraction of close binary central stars to be 15-20%, but these surveys have suffered from strong selection effect biases. We now have a 2 kpc volume-limited sample of planetary nebulae which can be surveyed to increase the known binary sample and determine a reliable binary fraction. Knowledge of the binary fraction in planetary nebulae, classification of discovered binaries, and correlation of binarity with the ejected common envelope will greatly improve our understanding of the formation of important objects like supernova Ia progenitors, cataclysmic variables, and subdwarf O and B stars. We propose to continue our volume-limited photometric monitoring campaign in both hemispheres.
National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360