论文标题
ASKAP - 位置快速无线电爆发的高时间分辨率和极化特性
High time resolution and polarisation properties of ASKAP-localised fast radio bursts
论文作者
论文摘要
将快速无线电爆发(FRB)的高时间和频率分辨率结合在一起,并了解其宿主星系特性,这提供了研究产生它们的发射机制及其通过其当地环境,宿主星系和galactactic介质的传播的影响的机会。澳大利亚平方公里阵列探路者(ASKAP)望远镜提供了此信息的第一个爆发合奏。在本文中,我们介绍了较高的时间和光谱分辨率,对五个局部FRB的完全极化观察结果补充了先前研究的ASKAP FRB〜181112的结果。我们发现每个FRB都是高度极化的,极化部分范围为80-100 \%,并且通常由线性极化主导。尽管我们的样品中的某些FRB具有与新兴原型相关的特性(即重复或显然是不重复的),而另一些FRB则表现出两者的特征,这表明存在FRB特性的连续性。当在高空分辨率上检查时,我们发现样本中的所有FRB都有多个子组件的证据,并且在比银河系中预期的水平上散射的水平。我们发现FRB性质的不同范围(例如散射时间,内在宽度和旋转度量)与其宿主星系的任何全球性能之间没有相关性。最散布的爆发位于其宿主星系的郊区,这表明源 - 本地环境而不是宿主星际介质可能是我们样本中散射的主要起源。
Combining high time and frequency resolution full-polarisation spectra of Fast Radio Bursts (FRBs) with knowledge of their host galaxy properties provides an opportunity to study both the emission mechanism generating them and the impact of their propagation through their local environment, host galaxy, and the intergalactic medium. The Australian Square Kilometre Array Pathfinder (ASKAP) telescope has provided the first ensemble of bursts with this information. In this paper, we present the high time and spectral resolution, full polarisation observations of five localised FRBs to complement the results published for the previously studied ASKAP FRB~181112. We find that every FRB is highly polarised, with polarisation fractions ranging from 80 -- 100\%, and that they are generally dominated by linear polarisation. While some FRBs in our sample exhibit properties associated with an emerging archetype (i.e., repeating or apparently non-repeating), others exhibit characteristic features of both, implying the existence of a continuum of FRB properties. When examined at high time resolution, we find that all FRBs in our sample have evidence for multiple sub-components and for scattering at a level greater than expected from the Milky Way. We find no correlation between the diverse range of FRB properties (e.g., scattering time, intrinsic width, and rotation measure) and any global property of their host galaxy. The most heavily scattered bursts reside in the outskirts of their host galaxies, suggesting that the source-local environment rather than the host interstellar medium is likely the dominant origin of the scattering in our sample.