论文标题
FRB 20180916b的高频研究使用100-m Effelsberg射电望远镜
High frequency study of FRB 20180916B using the 100-m Effelsberg radio telescope
论文作者
论文摘要
FRB 20180916b是重复的快速无线电爆发（FRB），活动期为16.33天。在以前的观察范围从$ \ sim 150-1400 $ MHz不等，活动窗口被发现频率取决于频率，较低的频率突发发生。在这项工作中，我们使用100米的Effelsberg射电望远镜以4 $ -8 $ 8 GHz介绍了该FRB爆发的最高频率检测。我们介绍了两个观察活动的结果。我们在整个活动期间进行了第一次活动，这没有导致检测。第二个活动是在一个主动窗口中以4 $ -8 GHz的速度进行，我们从色彩模型中预测，导致八次爆发检测。在Chime看到的活动峰之前，在1.35天，3.6天的窗口中检测到爆发，这表明色度扩展到较高的频率。与较低的频率相比，检测到的爆发具有较窄的时间宽度和较大的光谱宽度。它们都具有平坦的极化位置角扫角和高极化部分。由于银河系的方式，这些爆发还表现出衍射闪烁，随着$ f^{3.90 \ pm0.05} $缩放，并且随着时间的推移差异很大。我们发现频率尺度上的突发速率为$ f^{ - 2.6 \ pm0.2} $。最后，我们研究了频率依赖性对源模型的影响。
FRB 20180916B is a repeating fast radio burst (FRB) with an activity period of 16.33 days. In previous observations ranging from $\sim 150-1400$ MHz, the activity window was found to be frequency dependent, with lower frequency bursts occurring later. In this work, we present the highest-frequency detections of bursts from this FRB, using the 100-m Effelsberg Radio Telescope at 4$-$8 GHz. We present the results from two observing campaigns. We performed the first campaign over an entire activity period which resulted in no detections. The second campaign was in an active window at 4$-$8 GHz which we predicted from our modelling of chromaticity, resulting in eight burst detections. The bursts were detected in a window of 1.35 days, 3.6 days preceding the activity peak seen by CHIME, suggesting the chromaticity extends to higher frequency. The detected bursts have narrower temporal widths and larger spectral widths compared to lower frequencies. All of them have flat polarization position angle sweeps and high polarization fractions. The bursts also exhibit diffractive scintillation due to the Milky Way, following a $f^{3.90\pm0.05}$ scaling, and vary significantly over time. We find that burst rate across frequency scales as $f^{-2.6\pm0.2}$. Lastly, we examine implications of the frequency dependency on the source models.
