UP - logo
E-viri
Recenzirano Odprti dostop
  • Magnetospheric Multiscale O...
    Yao, S. T.; Shi, Q. Q.; Guo, R. L.; Yao, Z. H.; Tian, A. M.; Degeling, A. W.; Sun, W. J.; Liu, J.; Wang, X. G.; Zong, Q. G.; Zhang, H.; Pu, Z. Y.; Wang, L. H.; Fu, S. Y.; Xiao, C. J.; Russell, C. T.; Giles, B. L.; Feng, Y. Y.; Xiao, T.; Bai, S. C.; Shen, X. C.; Zhao, L. L.; Liu, H.

    Geophysical research letters, 28 January 2018, Letnik: 45, Številka: 2
    Journal Article, Web Resource

    The sudden enhancements of magnetic strength, named magnetic peaks (MPs), are often observed in the magnetosheath of magnetized planets. They are usually identified as flux ropes (FRs) or magnetic mirror mode structures. Previous studies of MPs are mostly on the magnetohydrodynamics (MHD) scale. In this study, an electron scale MP is reported in the Earth magnetosheath. We present a typical case with a scale of ~7 electron gyroradii and a duration of ~0.18 s. A strong magnetic disturbance and associated electrical current are detected. Electron vortex is found perpendicular to the magnetic field line and is self‐consist with the peak. We use multipoint spacecraft techniques to determine the propagation velocity of the MP structure and find that the magnetic peak does propagate relative to the plasma (ion) flow. This is very different from the magnetic mirror mode that does not propagate relative to the plasma flow. Furthermore, we developed an efficient method that can effectively distinguish “magnetic bottle like” and “FRs like” structures. The MP presented in this study is identified as magnetic bottle like type. The mechanism to generate the electron scale magnetic bottle like structure is still unclear, suggesting that new theory needs to be developed to understand such small‐scale phenomena. Key Points Electron scale magnetic peak is observed with the scale size of ~7 ρe (~0.06 ρi) in the magnetosheath Electron vortex is found perpendicular to the field line and the current system is consistent with the magnetic peak The magnetic peak is determined as magnetic bottle shape rather than flux rope by a new method