Probing the X-ray Reprocessing Geometry in High-Mass X-ray Binaries with the Chandra High Energy Transmission Grating

Abstract

A majority of stars reside in multiple systems, and a majority of massive stars appear in binaries. An important subset goes through an X-ray binary (XRB) phase, but the geometry of their X-ray reprocessing matter that gives rise to prominent spectral features such iron fluorescent X-ray emission remains not well understood. The similarity of XRB spectral features to those of Active Galactic Nuclei (AGN) in the X-rays motivates us to apply similar physical modeling for 10 well-known Galactic High Mass X-ray Binaries (HMXBs) observed with the Chandra High Energy Transmission Grating (HETG). Using two different state-of-the art models for X-ray reprocessing, that self-consistently model together Fe Kα fluorescent emission and scattered X-ray continua, we obtain unique insights into the geometry and kinematics of the accretion flow in these systems. Here, we present constraints on the shape as well as distance of the X-ray reprocessor from the accretion disk.