论文标题
自动检测费米GBM数据中的长期瞬变
Automatic detection of long-duration transients in Fermi-GBM data
论文作者
论文摘要
在时间域，多理智的天文学时代，对高能电磁天空的瞬态事件的检测变得比以往任何时候都变得更加重要。先前试图系统地搜索费米GBM数据中的板上无触点事件已限于短期信号，其可变性时间尺度小于〜1分钟，这是由于背景变化在较长的时间表上的优势。在这项研究中，我们旨在检测具有高灵敏度和GBM频谱完全覆盖的缓慢上升或长期瞬态事件。我们利用了早期开发的物理背景模型，提出了一种具有全自动数据分析管道的新型触发算法。广泛的模拟结果表明，开发的触发算法对亚捕食强度敏感，并且具有近乎最佳的检测性能。在实际的Fermi-GBM数据上进行了两个月的测试，该管道检测到300多个未触发的瞬态信号。对于这些瞬态检测之一，我们验证它起源于已知的天体物理源，即Vela X-1脉冲星，显示脉冲发射超过七个小时。更一般而言，此方法可以系统地搜索弱和/或长期瞬变。
In the era of time-domain, multi-messenger astronomy, the detection of transient events on the high-energy electromagnetic sky has become more important than ever. Previous attempts to systematically search for onboard-untriggered events in the data of Fermi-GBM have been limited to short-duration signals with variability time scales smaller than ~1 min due to the dominance of background variations on longer timescales. In this study, we aim at the detection of slowly rising or long-duration transient events with high sensitivity and full coverage of the GBM spectrum. We make use of our earlier developed physical background model, propose a novel trigger algorithm with a fully automatic data analysis pipeline. The results from extensive simulations demonstrate that the developed trigger algorithm is sensitive down to sub-Crab intensities, and has a near-optimal detection performance. During a two month test run on real Fermi-GBM data, the pipeline detected more than 300 untriggered transient signals. For one of these transient detections we verify that it originated from a known astrophysical source, namely the Vela X-1 pulsar, showing pulsed emission for more than seven hours. More generally, this method enables a systematic search for weak and/or long-duration transients.
