GIANT SPARKS AT COSMOLOGICAL DISTANCES?
GIANT SPARKS AT COSMOLOGICAL DISTANCES?
复制标题
DOI：
10.1088/0004-637x/797/1/70
复制
发表时间：
2014-02
期刊：
影响因子：
--
通讯作者：
S. Kulkarni;E. Ofek;J. Neill;Zheng Zheng-Zheng;M. Jurić
中科院分区：
文献类型：
--
作者：
S. Kulkarni;E. Ofek;J. Neill;Zheng Zheng-Zheng;M. Jurić
Lorimer等人报道了1.4 GHz高色散测量（DM）的毫秒持续时间明亮无线电脉冲，Keane等人，和Thornton等人，他们的全天速率是1004天-1，高于1001 Jy。相关的事件是“佩里顿”-类似的脉冲，分散的来源，但最肯定的是本地的。建议的快速射电暴（FRB）模型可以起源于地球的大气层，恒星日冕，其他星系，甚至在宇宙学距离。使用物理动机的假设结合观察到的属性，我们探索这些模型。在我们的分析中，我们关注Lorimer事件：一个30 Jy，5 ms持续时间的爆发，DM = 375 cm-3 pc，表现出陡峭的频率依赖脉冲宽度（火花）。为了完整，我们放弃了高DM由等离子体传播产生的假设，并假设源产生具有频率依赖性到达时间的脉冲（“啁啾信号”）。在这个框架内，我们探讨了一个方案，其中佩里顿，火花，和FRB都是发生在不同高度的大气现象。这个模型是特设的，因为我们不能解释为什么在较高海拔的佩里顿显示更大的DM或表现出更窄的脉冲。尽管如此，我们认为火花可能是一个佩里顿。最后，我们要说两点。首先，通过具有一公里（或更长）基线的干涉仪检测单个FRB将证明FRB起源于外星。其次，我们敦促天文学家继续观测和了解佩里顿，因为它们（至少）是FRB的一个可怕的前景。
Millisecond-duration bright radio pulses at 1.4 GHz with high dispersion measures (DMs) were reported by Lorimer et al., Keane et al., and Thornton et al. Their all-sky rate is ≈104 day−1 above ∼1 Jy. Related events are “Perytons”—similar pulsed, dispersed sources, but most certainly local. Suggested models of fast radio bursts (FRBs) can originate in Earth's atmosphere, in stellar coronae, in other galaxies, and even at cosmological distances. Using physically motivated assumptions combined with observed properties, we explore these models. In our analysis, we focus on the Lorimer event: a 30 Jy, 5 ms duration burst with DM = 375 cm−3 pc, exhibiting a steep frequency-dependent pulse width (the Sparker). To be complete, we drop the assumption that high DMs are produced by plasma propagation and assume that the source produces pulses with frequency-dependent arrival time (“chirped signals”). Within this framework, we explore a scenario in which Perytons, the Sparker, and the FRBs are all atmospheric phenomena occurring at different heights. This model is ad hoc in that we cannot explain why Perytons at higher altitudes show greater DMs or exhibit narrower pulses. Nonetheless, we argue that the Sparker may be a Peryton. We end with two remarks. First, the detection of a single FRB by an interferometer with a kilometer (or longer) baseline will prove that FRBs are of extraterrestrial origin. Second, we urge astronomers to pursue observations and understanding of Perytons since they form (at least) a formidable foreground for the FRBs.