Fast radio burst source properties from polarization measurements

Understand

Recent polarization measurements of fast radio bursts (FRBs) provide new insights on these enigmatic sources.

• We show that the nearly 100% linear polarization and small variation of the polarization position angles (PAs) of multiple bursts from the same source suggest that the radiation is produced near the surface of a strongly magnetized neutron star.
• As the emitted radiation travels through the magnetosphere, the electric vector of the X-mode wave adiabatically rotates and stays perpendicular to the local magnetic field direction.
• The PA freezes at a radius where the plasma density becomes too small to be able to turn the electric vector.