Probing Accretion Disks in BH XRBs with Reflection and Wind Spectroscopy
Abstract
Accretion disks in BH XRBs often exhibit two seemingly disconnected phenomena in X-ray spectra; disk reflection and powerful winds. The physical parameters associated with disks, such as inclination θ and density n, can be constrained by measuring disk reflection component primarily in hard X-ray band. Among those, disks in some of the transient BH XRBs are found to be non-equatorial orientation (e.g. θ ∼ 10°-40°) with the disk density of the order of log(n[cm-3]) ∼ 19-21. These objects also show clear blueshifted absorbers in Fe K band implying the presence of non-equatorial (polar) disk-winds with high velocities of v/c ∼ 0.05-0.1 in some cases. We propose in this work a novel approach to independently constrain the disk inclination θ and density n by utilizing the MHD-driven disk-wind model where the base of the wind gives a measure for disk density. In this scheme, reflection (Compton hump) and wind (absorption) can provide, as independent tools, two mutually exclusive diagnostics to probe disk inclination and density (n, θ). We will demonstrate a preliminary case study for multi-epoch Chandra/HETGS spectra of MAXI J1348-630 to show that two different methods successfully yield a broad agreement, and this technique can be further applied for other sources.
- Publication:
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44th COSPAR Scientific Assembly. Held 16-24 July
- Pub Date:
- July 2022
- Bibcode:
- 2022cosp...44.1766F