Asymmetric thin current sheets in the Earth's magnetotail.

H.V. Malova (1, 2) , L.M. Zelenyi (1) , V.Yu. Popov (1, 3) , Dominique C. Delcourt (4) , A.A. Petrukovich (1) , A. V. Runov (5)

1 IKI - Space Research Institute of the Russian Academy of Sciences
2 SINP - D.V. Skobeltsyn Institute of Nuclear Physics
3 Faculty of Physics [MSU, Moscow]
4 CETP - Centre d'étude des environnements terrestre et planétaires
5 IWF - Space Research Institute of Austrian Academy of Sciences

In a frame of self-consistent model of thin current sheets (TCSs), where the tension of magnetic field lines is balanced by the inertial force of ion motion, we investigated the influence of the asymmetry of plasma sources on the structure and spatial localization of the equilibrium solution. For simplicity only one ion source is considered. It is shown that the asymmetry of plasma sources does not modify dramatically the bulk of the current carried by ions at meandering orbits. Negative diamagnetic currents are significantly stronger at the side of a plasma source due to enhanced plasma density in this region. The center of TCS is displaced to the opposite side of the plasma source to keep the pressure balance. One could speculate that this phenomenon might be a cause of flapping motions of the TCS due to the natural variability of plasma sources.

Mots clés: magnetotail; thin current sheets; asymmetry

Domaines: Astrophysique [astro-ph]; Cosmologie et astrophysique extra-galactique [astro-ph.CO]; Physique des plasmas [physics.plasm-ph]

H.V. Malova, L.M. Zelenyi, V.Yu. Popov, Dominique C. Delcourt, A.A. Petrukovich, et al.. Asymmetric thin current sheets in the Earth's magnetotail.. Geophysical Research Letters, 2007, 34 (16), pp.L16108. ⟨10.1029/2007GL030011⟩. ⟨hal-00156454⟩