快速无线电爆发及其主机的直接定位
S Chatterjee1, C J Law2, R S Wharton1
1Cornell Center for Astrophysics and Planetary Science and Department of Astronomy, Cornell University, Ithaca, New York 14853, USA.
Nature
|January 6, 2017
概括
快速无线电爆发是一种神秘的宇宙无线电闪光. 重复的FRB 121102的精确定位揭示了它在一个持久的无线电源附近的起源,这表明一个活跃的银河系核或新型的银河系外源.
科学领域:
- 天文学与天体物理学
- 太空中的短暂
- 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来自银河系外的无线电闪光.
- 之前的FRB定位缺乏识别对应物或宿主星系的精度.
- FRB 121102是唯一已知重复的FRB源,因此对于理解FRB现象至关重要.
研究的目的:
- 为了实现FRB 121102重复的快速无线电爆发的亚秒定位.
- 确定FRB 121102的持久无线电源和潜在的光学对应物.
- 为了限制FRB 121102的起源和物理性质.
主要方法:
- 使用高时间分辨率的无线电干扰测量观测用于直接爆发成像.
- 使用非常长基线干扰测量 (VLBI) 来确定持久源的角大小.
- 使用深度成像搜索弱光学对应物.
主要成果:
- 实现了FRB 121102的亚弧秒定位, 确定其起源在持续无线电源的100亿弧秒内.
- 持久源表现出非热连续光谱和每日时间尺度上~10%的流量密度变化.
- 检测到一个微弱的光学对应物 (第25级),并且持久无线电源的角大小小小于1.7毫米弧秒.
结论:
- FRB 121102的源头与银河系起源或星系形成的位置不一致.
- 源头可能是低亮度的活跃星系核或新型的外星系物体.
- 对于可靠地关联微弱FRB对应物和了解它们的起源, 亚弧秒定位至关重要.
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