Av. Milovanov et al., Geometric description of the magnetic field and plasma coupling in the near-Earth stretched tail prior to a substorm, J ATMOS S-P, 63(7), 2001, pp. 705-721
Citations number
46
Categorie Soggetti
Earth Sciences
Journal title
JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS
Topological properties of the self-organized magnetic field and plasma turb
ulence in the near-Earth stretched tail prior to the magnetospheric substor
m onset are analyzed. We found that the magnetotail turbulence structures a
t the late substorm growth phase should be associated with the hierarchical
("singular") geometry; this geometry includes fractal objects, i.e., self-
similar "clumpy" structures with "voids" present on many scales. The fracta
l description of the self-organized magnetic field and electric current cou
pling in the tail has led us to the idea of the "geometric" formulation of
the basic physical processes in the tail; this formulation deals with certa
in topological "codes" (i.e., algebraic relations between the principal geo
metric parameters) and is an alternative of the more traditional approach b
ased on the direct analysis of the corresponding nonlinear differential equ
ations. A "topological scenario" for the substorm onset is further proposed
, and the relevant "codes" characterizing the microscopic structural proper
ties of the turbulence are obtained. The behavior of the Fourier energy den
sity spectra of the magnetic field and cross-tail electric current fluctuat
ions is discussed. The results of the numerical modeling of the turbulence
at the late growth phase are given. (C) 2001 Elsevier Science Ltd. All righ
ts reserved.