Abstract
Abstract
Multi-wave band synchrotron linear polarization of gamma-ray burst (GRB) afterglows is studied under the assumption of an anisotropic turbulent magnetic field with a coherence length of the plasma skin-depth scale in the downstream of forward shocks. We find that for typical GRBs, in comparison to optical polarization, the degree of radio polarization shows a similar temporal evolution but a significantly smaller peak value. This results from differences in observed intensity image shapes between the radio and optical bands. We also show that the degree of the polarization spectrum undergoes a gradual variation from the low- to the high-polarization regime above the intensity of the spectral peak frequency, and that the difference in polarization angles in the two regimes is zero or 90°. Thus, simultaneous multi-wave band polarimetric observations of GRB afterglows would be a new determinative test of the plasma-scale magnetic field model. We also discuss theoretical implications from the recent detection of radio linear polarization in GRB 171205A with the Atacama Large Millimeter/submillimeter Array and other models of magnetic field configuration.
Publisher
American Astronomical Society
Subject
Space and Planetary Science,Astronomy and Astrophysics
Cited by
9 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献