http://arxiv.org/abs/2202.05475
The curvature radiation is applied to the explain the circular polarisation of FRBs. Significant circular polarisation is reported in both apparent non-repeating and repeating FRBs. Curvature radiation can produce significant circular polarisation at the wing of the radiation beam. In the curvature radiation scenario, in order to see significant circular polarisation in FRBs (1) more energetic bursts, (2) burst with electrons having higher Lorentz factor, (3) a slowly rotating neutron star at the centre are required. Different rotational period of the central neutron star may explain why some FRBs have high circular polarisation, while others don’t. Considering possible difference in refractive index for the parallel and perpendicular component of electric field, the position angle may change rapidly over the narrow pulse window of the radiation beam. The position angle swing in FRBs may also be explained by this non-geometric origin, besides that of the rotating vector model.
H. Tong and H. Wang
Mon, 14 Feb 22
11/55
Comments: 7 pages, submitted