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来自重复的快速无线电爆发源的不同极化角度波动
R Luo1,2,3, B J Wang1,2, Y P Men1,2
1Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing, China.
Nature
|October 29, 2020
概括
快速无线电爆发 (FRB) 的观测显示出不同的极化角度波动. 这些发现支持磁层发射的起源,挑战基于冲击的辐射模型.
科学领域:
- 天体物理学
- 无线电天文学
背景情况:
- 快速无线电爆发 (FRB) 是一个持续数毫秒的无线电短暂信号,来源不明.
- 目前的理论表明,辐射机制涉及中子星磁层或相对论冲击.
- 极化观测对于了解FRB发射至关重要,
研究的目的:
- 通过详细的极化观测,研究快速无线电爆发 (FRB) 的发射机制.
- 来自单个FRB源 (FRB 180301) 的多重爆发的偏振特性.
主要方法:
- 从FRB 180301源观察到15个爆发.
- 在这些爆发中分析了极化角度的变化.
主要成果:
- 在15个分析爆发中的7个中观察到各种极化角度的波动.
- 在观察到的爆发中注意到极化特征的多样性.
结论:
- 在FRB 180301中观察到的多样化的极化角度波动与无线电辐射的磁层起源一致.
- 这些发现不利于使用相对论冲击作为FRB的主要发射机制的辐射模型.
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