PI: Kenneth Hinkle, NOAO, firstname.lastname@example.org
Address: NGSC, 950 N. Cherry Avenue, Tucson, AZ 85719, USA
CoI: Sean Brittain, Clemson University
CoI: Richard Joyce, NOAO
CoI: Robert Gehrz, University of Minnesota
Title: Keplerian disks around RV Tauri stars
Abstract: We propose to undertake 2.3 and 4.6 (micron) spectroscopy of RV Tauri stars to explore the circumstellar environment and mass loss process in these objects. RV Tauri stars are post-AGB objects and predominantly binaries. Many, if not all, RV Tauri stars have Keplerian circumbinary disks and are likely progenitors of bipolar PNe. Using experience gained from previous spectroscopy of the hotter post-AGB stars, we propose to use 4.6 (micron) spectroscopy to probe the gas at the surface of the circumbinary disk. Spectral lines formed in the disk are broadened by the disk rotation. For systems with a single line spectroscopic orbit and a known inclination the 4.6 (micron) line profile can be used to derive the masses of the stellar components. The 2.3 (micron) spectra contain lines of photospheric and circumstellar origin. We will model the disk based on the 4.6 (micron) results and apply this model to the complex 2.3 (micron) spectra to understand the line formation and related mass flow.
National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360