Magnetic field reversal in the turbulent environment around a repeating fast radio burst

Reshma Anna-Thomas; Liam Connor; Shi Dai; Yi Feng; Sarah Burke-Spolaor; Paz Beniamini; Yuan-Pei Yang; Yongkun Zhang; Kshitij Aggarwal; Casey J. Law; Di Li; Chenhui Niu; Shami Chatterjee; Marilyn Cruces; Ran Duan; Miroslav D. Filipovi; George Hobbs; Ryan S. Lynch; Chenchen Miao; Jiarui Niu; Stella K. Ocker; Chao-Wei Tsai; Pei Wang; Mengyao Xue; Jumei Yao; Wenfei Yu; Bing Zhang; Lei Zhang; Shiqiang Zhu; Weiwei Zhu

doi:10.1126/science.abo6526

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arXiv · 2202.11112

Magnetic field reversal in the turbulent environment around a repeating fast radio burst

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Abstract

Fast radio bursts (FRBs) are brief, intense flashes of radio waves from unidentified extragalactic sources. Polarized FRBs originate in highly magnetized environments. We report observations of the repeating FRB 20190520B spanning seventeen months , which show its amount of Faraday rotation is highly variable and twice changes its sign. The FRB also depolarizes below radio frequencies around 1 to 3 GHz. We interpret these properties as due to change in the parallel component of the integrated magnetic field along the line-of-sight, including reversals. This could result from propagation through a turbulent, magnetized screen of plasma located between $10^{-5}$ to 100 parsecs of the FRB source. This is consistent with the bursts passing through the stellar wind of a binary companion of the FRB source.

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Reshma Anna-Thomas, Liam Connor, Shi Dai, Yi Feng, Sarah Burke-Spolaor, Paz Beniamini, Yuan-Pei Yang, Yongkun Zhang, Kshitij Aggarwal, Casey J. Law, Di Li, Chenhui Niu, Shami Chatterjee, Marilyn Cruces, Ran Duan, Miroslav D. Filipovi, George Hobbs, Ryan S. Lynch, Chenchen Miao, Jiarui Niu, Stella K. Ocker, Chao-Wei Tsai, Pei Wang, Mengyao Xue, Jumei Yao, Wenfei Yu, Bing Zhang, Lei Zhang, Shiqiang Zhu, Weiwei Zhu. 2022-02-22. Magnetic field reversal in the turbulent environment around a repeating fast radio burst. https://doi.org/10.1126/science.abo6526

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