Parkes observations for project P1339 semester 2024OCTS_04

After applying an unsupervised machine learning pipeline to dataset, we found a series of "unknown-unknown" source in the sky. In the position right ascension 20:47:34.4 and declination -16:42:03, we found a broadband signal that last a few seconds. However, through the 60 second observation it repeats. The observations corresponded to testing the multibeam system by pointing each of the beams in turn at a pulsar. Our signal was detected in eight different beams in sequence (not the pulsar beam), with the same position at right ascension 20:47:34.4 and declination -16:42:03. Within a 0.23 deg radius to the anomalous event, GAIA has identified a total of four sources located within 100 pc. One of them is Gaia DR3 6886074198993703168, a white dwarf candidate. We speculate that the observed anomalous event could potentially be a stellar flare originating from one of the stars within the covered region. If this anomalous event comes from a white dwarf, then it could be the second confirmed radio active pulsar emitting white dwarf after AR Sco.

我们将无监督机器学习流水线（unsupervised machine learning pipeline）应用于数据集后，在天空中发现了一系列"未知未知"源（unknown-unknown source）。在赤经20:47:34.4、赤纬-16:42:03的位置处，我们探测到一段持续数秒的宽带信号，且该信号在60秒的观测周期内出现重复。本次观测对应于多波束系统（multibeam system）的测试环节：将系统各波束依次对准脉冲星（pulsar）进行扫描。我们的信号在8个依次切换的不同波束（非对准脉冲星的波束）中均被探测到，其对应的赤经与赤纬仍为20:47:34.4与-16:42:03。以此次异常事件为中心、半径0.23度的区域内，盖亚（GAIA）望远镜共识别出4个位于100秒差距范围内的天体。其中之一为盖亚DR3 6886074198993703168，即一颗白矮星候选体（white dwarf candidate）。我们推测，此次观测到的异常事件可能源自覆盖区域内某颗恒星的恒星耀斑（stellar flare）。若该异常事件确实来自一颗白矮星，则其可能成为继天蝎座AR（AR Sco）之后，第二颗被证实的射电活跃白矮星脉冲星（radio active pulsar emitting white dwarf）。