Polarimetry of binary systems: polars, magnetic CVs, XRBs

TL;DR

Polarimetry is a vital observational tool that reveals physical properties like magnetic fields, accretion zones, and jets in binary systems such as polars, magnetic CVs, and X-ray binaries, which are hard to study otherwise.

Contribution

This review highlights how optical/near-infrared polarimetry uniquely enables the study of magnetic fields, accretion zones, and jets in various interacting binary systems.

Findings

Estimates magnetic field strengths in magnetic CVs.

Maps accretion zones in polars.

Locates and characterizes jets in X-ray binaries.

Abstract

Polarimetry provides key physical information on the properties of interacting binary systems, sometimes difficult to obtain by any other type of observation. Indeed, radiation processes such as scattering by free electrons in the hot plasma above accretion discs, cyclotron emission by mildly relativistic electrons in the accretion shocks on the surface of highly magnetic white dwarfs and the optically thin synchrotron emission from jets can be observed. In this review, I will illustrate how optical/near-infrared polarimetry allows one to estimate magnetic field strengths and map the accretion zones in magnetic Cataclysmic Variables as well as determine the location and nature of jets and ejection events in X-ray binaries.