PI: Silas Laycock, University of Massachusetts, Lowell,
Address: Lowell, 01854 USA
CoI: Andrea Prestwich, CXC
CoI: Benjamin Williams, U. of Washington
CoI: Breanna Binder, U. of Washington
CoI: Jun Yang, Harvard-Smithsonian Center for Astrophysics
CoI: Rigel Cappallo, University of Massachusetts, Lowell
CoI: Allen Rogel, Bowling Green State U.
CoI: Ping Zhao, Harvard-Smithsonian Center for Astrophysics
Title: Blue Supergiant X-ray Binaries in our Nearest Starburst Galaxy
Abstract: In starburst galaxies the X-ray population is dominated by the relics of the most massive and short-lived stars (black hole and neutron star HMXBs). In the closest such galaxy IC 10, we have identified a young population of blue supergiant X-ray binary candidates. The systems include the progenitors of double-degenerate binaries, whose mergers are observed by LIGO as gravitational wave events. GMOS spectra will confirm IC 10 membership via radial velocity, and distinguish the luminous mass-losing stars in XRBs (e.g. Of, WR, Be, SNR) via NIII, He II, H, and nebular emission lines. IC 10 provides a unique age/metallicity segregated population which can be efficiently studied with a single GMOS mask. Comparison with the Galaxy, M31 and Magellanic Clouds provides a powerful probe of the role of age and metalicity in the evolution of XRB populations in star forming galaxies, and directly informs modeling of the black hole merger rate. Our primary targets are a population of X-ray selected blue supergiants (BSGs) identified by a (>6 sigma) statistical corellation between Chandra and optical photometric catalogs. We request very deep GMOS observations (augmenting prior shallow Hydra, GMOS datasets) to capture spectra for the most interesting but faintest objects, which include the majority of the 16 BSG candidates.
Program Type: Standard/Galactic
Run 1 (2017B): GEM-NQ/GMOSN -- 13.2hrs band 2 (GN-2017B-Q-46)
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