PI: Robert Hynes, Louisiana State U., firstname.lastname@example.org
Address: Department of Physics and Astronomy, 202 NICHOLSON HALL TOWER DRIVE, BATON ROUGE, LA 70803 United States
CoI: Joshua Wetuski, Louisiana State U.
CoI: Thomas Maccarone, Texas Technical University
CoI: Craig Heinke, University of Alberta
CoI: Peter Jonker, SRON
CoI: Manuel Torres, SRON
Title: The Hidden Population of Galactic Bulge Symbiotics Revealed in X-rays
Abstract: Symbiotic stars and symbiotic X-ray binaries contain white dwarfs or neutron stars accreting in the wind of a cool giant. They are binary evolution products, and may be Type Ia supernova progenitors. Historically many symbiotics have been identified based on strong emission lines, for example by Halpha surveys. It is increasingly becoming apparent that there is a hidden symbiotic population with weak emission lines likely due to the lack of a strong UV continuum from the white dwarf; this population may be larger than the strong line symbiotic population, and appears to include most neutron star symbiotics. We can identify these objects as X-ray selected cool giants which should not be instrinsic X-ray sources. We have identified a sample of 23 candidates in the Galactic Bulge, including two carbon stars. None stand out as Halpha excess sources in photometry, but three have already shown weak Halpha emission in low resolution spectra. We propose to obtain higher resolution Gemini/GMOS spectra around Halpha to confirm their spectral classification and search for weak emission lines. Confirmation of a symbotic classification for many of these objects will demonstrate the existence of a substantial population of weak line symbiotics.
Program Type: Standard/Galactic
Run 1 (2018A): GEM-SQ/GMOSS -- 13hrs band 3 (GS-2018A-Q-314 )
National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360