PI: Saeqa Dil Vrtilek, Smithsonian Astrophysical Observatory, email@example.com
Address: High Energy Astrophysics, 60 Garden Street, Mail Stop 83, Cambridge, MA 02138, USA
CoI: Charith Peris, Northeastern U Pre-doctoral fellow at SAO
CoI: Jan Cechura, Charles U Pre-doctoral fellow at SAO
Title: Imaging Black Hole and Neutron Star Binaries
Abstract: Tomography offers one of the few approaches to spatial examination of X-ray binaries which enables us to study the geometry of the accretion flow in detail and to examine spectral signatures that differentiate between neutron stars and black holes. We propose to observe two systems (the black hole candidate V1408 Aql and the neutron star system, V801 Ara) which are especially suitable for the study of disk evolution and instabilities. The optical variations of V1408 Aql have been variously attributed to a heated secondary or a thin disk, whereas its X-ray spectrum is attributed to a pure disk. Our tomographic images will allow us to identify unambiguously the presence or absence of a disk. V801 Ara shows superbursts in addition to bursts making it a prime candidate to show disk eccentricity, which provides important clues about the nature of the disk evolution. The data obtained will also allow us to improve the radial velocities, measure K2 from the irradiated emission lines, and refine the mass ratios by fitting the rotational broadening of the secondary for each system.
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