PI: Sebastian Gomez, Harvard U., firstname.lastname@example.org
Address: Astronomy Department, 60 Garden Street, Cambridge, Massachusetts 02138 United States
CoI: Jonathan Grindlay, Harvard U.
Title: Spectroscopy of a likely new black hole X-ray binary and Cygnus X-1 progenitor
Abstract: HD96670 is a single-line spectroscopic binary made up of an O8.5V primary with variable HeII emission, and an unseen secondary (Sota, et al. 2014). We observed the source and determined a mass function of $f(M) = 0.1161 pm 0.0046$ M_Sun. For an O8.5 primary, this implies a minimum secondary mass of $M_2 > 3.5 pm 0.5 M_Sun$, ruling out a neutron star or white dwarf secondary. We don’t see any spectral signatures that can be associated with a main sequence companion $> 3.5$M_Sun. The source also shows X-ray emission above 10keV with a photon index $sim 2.5$ (Grindlay, et al. in prep). These arguments favor a black hole secondary, if confirmed this would be the third to fifth dynamically confirmed black hole high mass X-ray binary known in the galaxy (Besides Cyg X-1 and MWC 656).
Program Type: Standard/LCO
Run 1 (2017B): LCO-1m/NRES -- 10hrs
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