PI: Douglas Gies, Georgia State University, email@example.com
Address: Physics Department, P.O. Box 4106, Atlanta, GA 30302-4106, USA
CoI: Todd Hillwig, Valparaiso Univeristy
CoI: Stephen Williams, Georgia State University
Title: Orbits for New Massive Binaries
Abstract: The fundamental properties (mass and radius) of the most massive stars are still poorly known because of the paucity of data on the rare eclipsing binaries among the O-type stars. We are pursuing a program of spectroscopy of southern sky massive stars to find new candidates for mass determination and to find new examples of binaries at key stages of evolutionary interaction. Here we propose to complete the radial velocity and spectral analyses of some 27 systems that we have identified as probable binaries through recent spectroscopy with the CTIO 1.5-m telescope. The new observations will provide accurate orbital periods, fill the gaps in orbital coverage, and help us identify some long-period systems. We will use a Doppler tomography algorithm to reconstruct and characterize the spectra of the individual components, and we will combine the spectroscopic results with light curve investigations of the eclipsing systems to determine masses, radii, and distance.
National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360