Profiles of electron temperature and B-z along Earth's magnetotail

A. V. Artemyev (1, 2) , A. A. Petrukovich (1) , R. Nakamura (3) , L.M. Zelenyi (1)

1 IKI - Space Research Institute of the Russian Academy of Sciences
2 LPC2E - Laboratoire de Physique et Chimie de l'Environnement et de l'Espace
3 IWF - Space Research Institute of Austrian Academy of Sciences

We study the electron temperature distribution and the structure of the current sheet along the magnetotail using simultaneous observations from THEMIS spacecraft. We perform a statistical study of 40 crossings of the current sheet when the three spacecraft THB, THC, and THD were distributed along the tail in the vicinity of midnight with coordinates X-B is an element of [-30 R-E, -20 R-E], X-C is an element of [-20 R-E, -15 R-E], and XD similar to -10 R-E. We obtain profiles of the average electron temperature < T-e > and the average magnetic field < B-z > along the tail. Electron temperature and < B-z > increase towards the Earth with almost the same rates (i.e., ratio < T-e > / < B-z > approximate to 2 keV/7 nT is approximately constant along the tail). We also use statistics of 102 crossings of the current sheet from THB and THC to estimate dependence of T-e and B-z distributions on geomagnetic activity. The ratio < T-e > / < B-z > depends on geomagnetic activity only slightly. Additionally we demonstrate that anisotropy of the electron temperature < T-parallel to/ T-perpendicular to > approximate to 1.1 is almost constant along the tail for X is an element of [-30 R-E, -10 R-E].

Keywords: Magnetospheric physics; magnetotail; plasma convection; plasma sheet

Domains: Sciences of the Universe [physics]

A. V. Artemyev, A. A. Petrukovich, R. Nakamura, L.M. Zelenyi. Profiles of electron temperature and B-z along Earth's magnetotail. Annales Geophysicae, 2013, 31, pp.1109-1114. ⟨10.5194/angeo-31-1109-2013⟩. ⟨insu-01256271⟩