We study scaling in fluctuations of the geomagnetic indices (AE, AU, and AL) that provide a measure of magnetospheric activity and of the epsilon parameter which is a measure of the solar wind driver. Generalized structure function (GSF) analysis shows that fluctuations exhibit self-similar scaling up to about 1 hour for the AU index and about 2 hours for AL, AE and epsilon when the most extreme fluctuations over 10 standard deviations are excluded. The scaling exponents of the GSF are found to be similar for the three AE indices, and to differ significantly from that of epsilon. This is corroborated by direct comparison of their rescaled probability density functions.
Real-time prediction of two geomagnetic storms using Solar Orbiter as a far upstream solar wind monitor
Austrian Space Weather Office, GeoSphere Austria(奥地利空间天气办公室,GeoSphere奥地利);Blackett Laboratory, Imperial College London(布莱克特实验室,伦敦帝国理工学院);Institute of Physics, University of Graz(格拉茨大学物理研究所)
Investigating potential benefits of future sub-L1 missions with STEREO-A
Austrian Space Weather Office, GeoSphere Austria(奥地利空间天气办公室,地球圈奥地利);Space Science Center and Department of Physics and Astronomy, University of New Hampshire(新罕布什尔大学空间科学中心及物理与天文学系);Conrad Observatory, GeoSphere Austria(康拉德天文台,地球圈奥地利);Institute of Physics, University of Graz(格拉茨大学物理研究所);Kanzelhöhe Observatory for Solar and Environmental Research, University of Graz(格拉茨大学坎泽勒赫厄太阳与环境研究天文台);Community Coordinated Modeling Center, NASA Goddard Space Flight Center(NASA戈达德太空飞行中心社区协调建模中心);Universities Space Research Association(大学空间研究协会)
Recurrent galactic cosmic-ray flux modulation in L1 and geomagnetic activity during the declining phase of the solar cycle 24
内日球层中银河宇宙线(GCR)通量的短期变化($<$ 1个月)主要与高速太阳风流(HSS)和行星际(IP)对应的日冕物质抛射(ICME)的通过有关。在第24太阳周期(2016年2月至2017年7月)拉格朗日点L1附近的下降部分,欧空局LISA探路者(LPF)航天器上飞行的粒子探测器收集的数据允许研究70 MeV n $^{-1}$以上的经常性宇宙射线通量调制的特征。%当太阳风速度为$>$ 400 km s $^{-1}$和/或IP磁场强度$>$ 10 nT时,观察到这些调制。结果表明,在HSS和ICME过境之前,单个调制的幅度和演化以独特的方式依赖于IP等离子体参数和粒子通量强度。通过将低通滤波器数据与国际空间站上的AMS-02磁谱仪实验同时收集的数据和地球极地中子监测器收集的数据进行比较,研究了在周期性短期变化期间不同能量下的GCR通量调制。其目的还在于确定近实时粒子观测要求,以理清GCR通量的长期和短期变化的作用,从而评价空间高灵敏度仪器的性能,如未来用于引力波探测的干涉仪。最后,讨论了2016-2017年L1周期性GCR通量变化观测与弱到中等地磁活动之间的关系。当IP磁场的B $_z$分量指向北方时,短期周期性GCR通量变化是周期性地磁活动的良好代表。
Tracking nonlinear solar-wind dynamics over three solar cycles using Wind observations
Instituto de Física del Noroeste Argentino, CONICET(阿根廷西北物理研究所,阿根廷国家科学研究委员会);Universidad Nacional de Tucumán(图库曼国立大学);Departamento de Física, Facultad de Ciencias Exactas y Tecnología, Universidad Nacional de Tucumán(图库曼国立大学理学院技术系物理系)
A study on the contribution of the interplanetary medium in radio occultation experiments
Indian Institute of Technology Indore(印度印多尔理工学院);Indian Space Research Organization, Vikram Sarabhai Space Centre(印度空间研究组织,维克拉姆·萨拉巴hai航天中心);ISRO Telemetry Tracking and Command Network(印度空间研究组织遥测跟踪与指令网络);The University of Tokyo(东京大学)