Multi-satellite observations of energy transport during an intense geomagnetic storm

• Published in: Astrophysics and space science 2016-05, Vol.361 (5), p.1, Article 168
• Main Authors: Yang, Jian, Ma, Yuduan, Duan, Aiying, Dunlop, M. W.
• Format: Article
• Language: English
• Subjects: Astrobiology; Astronomy; Astrophysics; Astrophysics and Astroparticles; Cosmology; Earth; Energy conversion; Fluctuations; Geophysics; Magnetic fields; Observations and Techniques; Original Article; Physics; Physics and Astronomy; Probes; Satellites; Solar energy; Solar physics; Space Exploration and Astronautics; Space Sciences (including Extraterrestrial Physics; Storms; Sun
• ISSN: 0004-640X; 1572-946X
• DOI: 10.1007/s10509-016-2745-9

Energy transport during a geomagnetic substorm is a very important process for solar wind-magnetosphere energy coupling and the energy cycle in the magnetotail. In this paper, we use magnetotail data from the five THEMIS probes and two Cluster satellites on the dayside to investigate the energy transport of one intense storm during the period from 08 March to 11 March 2008 at large spatial-temporal scales. Simultaneous observations of the five THEMIS probes indicate that there is a stronger and earlier duskward energy flux density in the near-Earth magnetotail than that in the mid-tail in the initial phase. Low energy particles inject earthward from the dusk flank. Stronger and more variable earthward energy flux density is observed in the mid-tail compared to that near Earth in the main phase; mainly caused by high-speed flow. Tailward energy flux was observed in the near-Earth and mid-tail regions during the recovery phase. Dayside data observed by two Cluster satellites show that the duskward energy flux may be related to stable solar wind input. Tailward energy flux on the dayside should experience some energy conversion process in the magnetotail before it can provide the earthward energy flux in the magnetotail for this intense storm. The strongest energy transport observed by the nightside probes occurs in the main phase. However, the strongest energy measured by the dayside satellites is in the recovery phase without intense activities, two hours later. Different features of the energy transport in the three phases of the storm may be closely related to the different physical processes such as the energy entry, westward drift, particle injection or other potential mechanisms.