论文标题
圆形色带耀斑期间准周期性的起源
The origin of quasi-periodicities during circular ribbon flares
论文作者
论文摘要
带有风扇的磁性拓扑结构的太阳耀斑可以形成圆形丝带。先前的研究基于Xu等人2014年3月5日对太阳耀斑的Hαline观察结果。 （2017年）揭示了磁风扇螺旋的均匀和连续旋转。耀斑时间曲线的初步分析显示，在硬X射线，Hα和微波炉中具有相似特性的准周期搏动（QPP）。在这项工作中，我们解决了观察到的周期性与：电子或等离子体加热的周期性加速有关的过程？从风扇中心（内色带R1），圆形色带（R2），远程源（R3）和位于R2和R3之间的细长色带（R4）中分析了QPP。使用相关，傅立叶，小波和经验模式分解方法。将Hα排放中的QPP与微波和X射线发射中的QPP进行比较。我们发现多波长QPP，周期约为150 s，125 s和190 s。 150秒的周期可在Hα，硬X射线和微波排放中共存，这使我们能够将其与Flare内核R1和R2连接起来。这些内核在空间上与主要火炬能释放的位点一致。在衰减阶段的细长色带R4的Hα排放和微波发射的Hα排放中发现了125 s。 190 s时期存在于所有耀斑阶段的发射中，在远程源R3和细长的色带R4的Hα发射中，软X射线和4--8 GHz的微波。我们将主要的150-S QPP与风扇中发生的滑动重新连接机构联系起来。我们建议，伸长色带中125 s的周期可能是由将主要重新连接位点与远程脚关的外脊柱的扭结振荡引起的。 190 s的周期与3分钟的黑子振荡有关。
Solar flares with a fan-spine magnetic topology can form circular ribbons. The previous study based on Hαline observations of the solar flares during March 05, 2014 by Xu et al. (2017) revealed uniform and continuous rotation of the magnetic fan-spine. Preliminary analysis of the flare time profiles revealed quasi-periodic pulsations (QPPs) with similar properties in hard X-rays, Hα, and microwaves. In this work, we address which process the observed periodicities are related to: periodic acceleration of electrons or plasma heating? QPPs are analysed in the Hαemission from the centre of the fan (inner ribbon R1), a circular ribbon (R2), a remote source (R3), and an elongated ribbon (R4) located between R2 and R3. The methods of correlation, Fourier, wavelet, and empirical mode decomposition are used. QPPs in Hαemission are compared with those in microwave and X-ray emission. We found multi-wavelength QPPs with periods around 150 s, 125 s, and 190 s. The 150-s period is seen to co-exist in Hα, hard X-rays, and microwave emissions, that allowed us to connect it with flare kernels R1 and R2. These kernels spatially coincide with the site of the primary flare energy release. The 125-s period is found in the Hαemission of the elongated ribbon R4 and the microwave emission at 5.7 GHz during the decay phase. The 190-s period is present in the emission during all flare phases in the Hαemission of both the remote source R3 and the elongated ribbon R4, in soft X-rays, and microwaves at 4--8 GHz. We connected the dominant 150-s QPPs with the slipping reconnection mechanism occurring in the fan. We suggested that the period of 125 s in the elongated ribbon can be caused by a kink oscillation of the outer spine connecting the primary reconnection site with the remote footpoint. The period of 190 s is associated with the 3-min sunspot oscillations.
