Pair-beam propagation in a magnetized plasma for modeling the polarized radiation emission from gamma-ray bursts in laboratory astrophysics experiments.

The propagation of a relativistic electron-positron beam in a magnetized electron-ion plasma is studied, focusing on the polarization of the radiation generated in this case. Special emphasis is laid on investigating the polarization of the generated radiation for a range of beam-plasma parameters, transverse and longitudinal beam sizes, and the external magnetic fields. Our results not only help in understanding the high degrees of circular polarization observed in gamma-ray bursts, but they also help in distinguishing the different modes associated with the filamentation dynamics of the pair beam in laboratory astrophysics experiments.

Polarized Light from the Transportation of a Matter-Antimatter Beam in a Plasma.

A relativistic electron-positron beam propagating through a magnetized electron-ion plasma is shown to generate both circularly and linearly polarized synchrotron radiations, which is intrinsically linked with asymmetric energy dissipation of the pair beam during the filamentation instability dynamics in the background plasma. The ratio of both polarizations |⟨P_{circ}⟩/⟨P_{lin}⟩|∼0.15, occurring for a wide range of beam-plasma parameters, can help in understanding the recent observation of circularly polarized radiation from gamma-ray bursts.