An observational method for fast stochastic X-ray polarimetry-timing

Understand

The upcoming launch of the first space based X-ray polarimeter in $\sim 40$ years will provide powerful new diagnostic information to study accreting compact objects.

• In particular, analysis of rapid variability of the polarisation degree and angle will provide the opportunity to probe the relativistic motions of material in the strong gravitational fields close to the compact objects, and enable new methods to measure black hole and neutron star parameters.
• However, polarisation properties are measured in a statistical sense, and a statistically significant polarisation detection requires a fairly long exposure, even for the brightest objects.
• Therefore, the sub-minute timescales of interest are not accessible using a direct time-resolved analysis of polarisation degree and angle.