论文标题
太阳周期中弱化的地球球对冠状质量弹出特性的影响
Effect of the Weakened Heliosphere in Solar Cycle 24 on the Properties of Coronal Mass Ejections
论文作者
论文摘要
太阳周期(SC)24到2019年底已经结束,提供了两个完整周期的信息,以了解SC 24的表现,这是太空年龄中最小的周期,导致压力降低表明的地球层状态较弱。地球层状态的反应是使冠状质量弹出(CMES)看起来比SC 23中的物理上大,但是它们的磁含量已被稀释,从而导致地理位置较低。在SC 24中,Heliosperic磁场也较低,导致高能太阳能粒子(SEP)事件的缺乏。这些太空天气事件紧随其后的(FW)CME。除FW CME以外,SC 24中的所有数量都较高。在这两个周期中,CME速率与Sunspot数(SSN)相关性都很高,但是SC 24中的速率更快。我们重新审视了肢体CME的研究(那些在肢体中的源区域(从肢体中有30度以内的源区域)进行了研究。我们发现,肢体CME在SC 24中的速度较慢,就像一般人群一样,但更宽。肢体光环CME遵循较慢的SC-24 CME趋势。但是,SC-24 CMES距离太阳较短。因此,较慢的CME迅速成为HALOS,这清楚地表明了CMES上较弱的Heliospher态的反应。我们可以进一步将地球层状态固定为改变CME特性的原因,因为相关的耀斑在两个循环中具有相似的分布,而不受地球层状态的影响。
Solar cycle (SC) 24 has come to an end by the end of 2019, providing information on two full cycles to understand the manifestations of SC 24, the smallest cycle in the Space Age that has resulted in a weak heliospheric state indicated by the reduced pressure. The backreaction of the heliospheric state is to make the coronal mass ejections (CMEs) appear physically bigger than in SC 23, but their magnetic content has been diluted resulting in a lower geoeffectiveness. The heliospheric magnetic field is also lower in SC 24, leading to the dearth of high-energy solar energetic particle (SEP) events. These space weather events closely follow fast and wide (FW) CMEs. All but FW CMEs are higher in number in SC 24. The CME rate vs. sunspot number (SSN) correlation is high in both cycles but the rate increases faster in SC 24. We revisit the study of limb CMEs (those with source regions within 30 degrees from the limb) previously studied over partial cycles. We find that limb CMEs are slower in SC 24 as in the general population but wider. Limb halo CMEs follow the same trend of slower SC-24 CMEs. However, the SC-24 CMEs become halos at a shorter distance from the Sun. Thus, slower CMEs becoming halos sooner is a clear indication of the backreaction of the weaker heliospheric state on CMEs. We can further pin down the heliospheric state as the reason for the altered CME properties because the associated flares have similar distributions in the two cycles, unaffected by the heliospheric state.