Open AccessElectron-scale Current Layers in the Martian Magnetotail: Spatial Scaling and Properties of Embedding
Author(s) -
Е. Е. Григоренко,
Л. М. Зеленый,
С. Д. Шувалов,
H. V. Malova,
E. Dubinin
Publication year - 2022
Publication title -
astrophysical journal/the astrophysical journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.376
H-Index - 489
eISSN - 1538-4357
pISSN - 0004-637X
DOI - 10.3847/1538-4357/ac4bd8
Subject(s) - gyroradius , physics , kinetic energy , electron , ion , martian , magnetic field , plasma , radius , scaling , electron temperature , spacecraft , thermal , computational physics , astrophysics , atomic physics , mars exploration program , astrobiology , astronomy , geometry , nuclear physics , classical mechanics , meteorology , computer security , mathematics , quantum mechanics , computer science
Current sheets (CSs) are widespread objects in space plasma capable of storing and, then, explosively releasing the accumulated magnetic energy. In planetary magnetotails the cross-tail CS plays an important role in the global dynamics of the tail and in the transformation of the magnetic energy into the kinetic and thermal energies of the ambient plasma. We have analyzed 114 crossings of the cross-tail CS by the MAVEN spacecraft at X MSO ∼ [−1.0, −2.8] R M . Magnetic field observations with high time resolution allowed the observation of the inner superthin CS (STCS) with a half-thickness L STCS ∼ (1–100) ρ e ( ρ e is the gyroradius of thermal electrons) in 75 intervals of the CS crossings from our database. The STCS was embedded into a thicker ion-scale CS and provides 10%–50% of the total current density in the cross-tail CS. Our analysis has shown that the observed L STCS and the embedding parameter, σ emb , characterizing the contribution of the STCS to the total current density in the CS are well described by the novel analytical kinetic model of a multilayered CS with an inner embedded electron-scale layer: L STCS ∼ (0.9–1.2) λ and σ emb ∼ (0.9–1.2) σ model , where the universal spatial scaling λ ∼ δ i 2 / ρ P and the embedding parameter σ model ∼ δ i / ρ P are determined by the local ion inertial length ( δ i ) and gyroradius of thermal protons ( ρ P ) in the STCS.