日球层等离子体片及其行星空间天气效应

A review of heliospheric plasma sheets and their impacts on planetary space weather

日球层等离子体片是出现在日球层电流片附近的等离子体结构,具有离子数密度明显增强、磁场总强度下降、等离子体β增大等特征,是行星际扰动和行星空间天气的重要驱动源,被广泛关注和研究.日球层等离子体片内可能存在局地电流片、等离子体波动和磁岛,也引起日趋深入的讨论.本文简要介绍有关日球层等离子体片的一些研究进展,重点关注日球层等离子体片的源区、成因、就地观测特征和行星空间天气效应,并尝试分析一些值得探讨的科学问题.

The heliospheric plasma sheet(HPS)is generally viewed as a structure straddling a heliospheric current sheet(HCS)where the interplanetary magnetic field changes polarity.It is generally characterized by enhanced density,depressed magnetic field and enhanced plasmaβ.The HPSs are important drivers of the interplanetary disturbances and planetary space weather,and have received extensive attention in the literature.The HPSs are possibly filled with current sheets,waves,and magnetic islands,which are receiving much more attentions recently.In this brief review,we introduce the research progress of the HPSs,with focus on their sources,formation mechanisms,properties based on in-situ observations,as well as the potential impacts on planetary space weather.Also,we try to discuss some points that are still under debate and remain elusive.