ASKAP detection of periodic and elliptically polarized radio pulses from UV Ceti
ASKAP detection of periodic and elliptically polarized radio pulses from UV Ceti
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DOI：
10.1093/mnras/stz1684
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发表时间：
2019-06
影响因子：
4.8
通讯作者：
A. Zic;A. Stewart;E. Lenc;T. Murphy;C. Lynch;D. Kaplan;A. Hotan;C. Anderson;J. Bunton;
中科院分区：
文献类型：
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作者：
A. Zic;A. Stewart;E. Lenc;T. Murphy;C. Lynch;D. Kaplan;A. Hotan;C. Anderson;J. Bunton;
众所周知，活跃的M矮星会产生爆发的射电辐射，多波长研究表明，在这些恒星中发生了类似太阳的磁活动。然而，在太阳活动范式中，来自活跃的M矮星的相干爆发通常很难解释。我们介绍了澳大利亚正方形阵列探路器(ASKAP)对中心频率为888 MHz的紫外线CETI的观测。我们探测到几个周期性的相干脉冲发生在与UV CETI旋转周期一致的时间尺度上。脉冲发射的性质表明，它们起源于电子回旋脉泽不稳定性，在一个比估计源高度的平均日冕密度低至少7个数量级的空腔中。这些结果证实了在活跃的M矮星中可以发生极光活动，这表明这些恒星标志着从类太阳行为向极光磁层行为转变的开始。这些结果证明了ASKAP探测来自活动恒星和其他系统的极化相干爆发的能力。
Active M dwarfs are known to produce bursty radio emission, and multiwavelength studies have shown that solar-like magnetic activity occurs in these stars. However, coherent bursts from active M dwarfs have often been difficult to interpret in the solar activity paradigm. We present Australian Square Array Pathfinder (ASKAP) observations of UV Ceti at a central frequency of 888 MHz. We detect several periodic, coherent pulses occurring over a time-scale consistent with the rotational period of UV Ceti. The properties of the pulsed emission show that they originate from the electron cyclotron maser instability, in a cavity at least 7 orders of magnitude less dense than the mean coronal density at the estimated source altitude. These results confirm that auroral activity can occur in active M dwarfs, suggesting that these stars mark the beginning of the transition from solar-like to auroral magnetospheric behaviour. These results demonstrate the capabilities of ASKAP for detecting polarized, coherent bursts from active stars and other systems.