The Relative Importance of Faraday Rotation and QED Birefringence for the Linear Polarization of X-rays from Mass Accreting Black Holes
arXiv:2104.08587 · doi:10.3847/1538-4357/abf931
Abstract
The upcoming IXPE (2-8 keV) and XL-Calibur (15-75 keV) missions will make it possible to measure the linear polarization of X-rays from mass accreting stellar mass black holes with unprecedented sensitivity, enabling the accurate measurement of percent-level and in some cases even sub-percent level polarization fractions. The measurements are expected to constrain the spins, inclinations, and the structure of the accretion flows of the observed black holes. The effects of Faraday rotation and birefringence of the Quantum Electrodynamics (QED) vacuum may impact the observable polarization fractions and angles, complicating the interpretation of the results. We estimate the importance of both effects for X-rays from stellar mass and supermassive black holes and discuss the implications of the results for the upcoming IXPE and XL-Calibur observations.
7 pages, 3 figures, accepted for publication in the Astrophysical Journal
References in corpus (6)
- A Parallax Distance to the Microquasar GRS 1915+105 and a Revised Estimate of its Black Hole Mass
- Constraining the size of the corona with fully relativistic calculations of spectra of extended corona. I - the Monte Carlo radiative transfer code
- XL-Calibur -- a second-generation balloon-borne hard X-ray polarimetry mission
- Accretion geometry of the black-hole binary Cygnus X-1 from X-ray polarimetry
- The X-ray Polarization of the Accretion Disk Coronae of Active Galactic Nuclei
- X-ray Polarization from Black Holes: GEMS Scientific White Paper