论文标题
脉冲星磁层中的Alfvén波模式转换
Alfvén wave mode conversion in pulsar magnetospheres
论文作者
论文摘要
无线电发射异常与2016年Vela Pulsar的故障一致，可能是由恒星地震引起的，该星星将Alfvén波发射到磁层中，扰乱了原始的无线电发射区。为了量化Alfvén波的寿命，我们研究了可能的能量损失机制，即Alfvénwaves转化为快速磁波波。使用无轴对称力的模拟，我们遵循从恒星表面发射的Alfvén波的传播，其幅度很小，进入了无力的双极脉冲脉冲磁层的封闭区域。我们观察到模式转换在理想的无力度制度中。 Alfvén波通过赤道的第一次通过期间的转换效率可能很大，对于在它们远离恒星时达到较大幅度的波，或在靠近Y点的野外线上传播。然而，由于随后的通道上的逐步降低，并且在封闭的野外线上仍然存在相当大的Alfvén功率，因此转化效率降低了。因此，尽管发生了一些泄漏到快速模式的泄漏，但我们需要详细了解原始淬火，以说明单独的模式转换是否会导致PULSAR在短时间内重新激活。
The radio emission anomaly coincident with the 2016 glitch of the Vela pulsar may be caused by a star quake that launches Alfvén waves into the magnetosphere, disturbing the original radio emitting region. To quantify the lifetime of the Alfvén waves, we investigate a possible energy loss mechanism, the conversion of Alfvénwaves into fast magnetosonic waves. Using axisymmetric force-free simulations, we follow the propagation of Alfvén waves launched from the stellar surface with small amplitude into the closed zone of a force-free dipolar pulsar magnetosphere. We observe mode conversion happening in the ideal force-free regime. The conversion efficiency during the first passage of the Alfvén wave through the equator can be large, for waves that reach large amplitudes as they travel away from the star, or propagate on the field lines passing close to the Y-point. However, the conversion efficiency is reduced due to dephasing on subsequent passages and considerable Alfvén power on the closed field lines remains. Thus while some leakage into the fast mode happens, we need detailed understanding of the original quenching in order to say whether mode conversion alone can lead to reactivation of the pulsar on a short timescale.
