We report the detection of an extreme flux decrease accompanied by clear dispersion measure (DM) and rotation measure (RM) variations for pulsar B1929+10 during the 110 minute radio observation with the Five-hundred-meter Aperture Spherical radio Telescope. The radio flux decreases by 2–3 orders of magnitude within a rapid timescale of about 20 minutes. Meanwhile, the variations of DM and RM are approximately 0.05 pc cm⁻³ and 0.7 rad m⁻², respectively. Frequency-dependent analysis of DM indicates an extremely weak chromatic DM feature, which does not notably affect the radiative behavior detected. Moreover, the pulsar timing analysis shows an additional time delay from 100 μs to 400 μs in the event. These results are speculated to be due to the eclipse and bend for the radio emission of pulsar B1929+10 by a highly dense outflow from the pulsar. This not only impacts the intrinsic radio emission feature but also affects the pulsar timing behavior. Nevertheless, a plasma lens effect lasting around 20 minutes could also be responsible for the event.

中文翻译：

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Pulsar B1929+10 的极端无线电波动


我们报告了在使用 500 米口径球面射电望远镜进行 110 分钟射电观测期间，检测到脉冲星 B1929+10 的磁通量极度降低，并伴有清晰的色散测量 （DM） 和旋转测量 （RM） 变化。射电通量在大约 20 分钟的快速时间尺度内下降了 2-3 个数量级。同时，DM 和 RM 的变化分别约为 0.05 pc ^cm-3 和 0.7 rad ^m-2。DM 的频率依赖性分析表明色度 DM 特征极弱，不会显着影响检测到的辐射行为。此外，脉冲星时序分析显示，事件中还有从 100 μs 到 400 μs 的额外时间延迟。这些结果被推测是由于脉冲星 B1929+10 的高密度流出物对脉冲星 B1929+10 的无线电发射造成的日食和弯曲。这不仅会影响固有无线电发射功能，还会影响脉冲星定时行为。尽管如此，持续约 20 分钟的等离子镜头效果也可能是导致该事件的原因。