Premium
The interchange cycle: A fundamental mode of magnetic flux circulation for northward interplanetary magnetic field
Author(s) -
Watanabe Masakazu,
Sofko George J.
Publication year - 2009
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2008gl036682
Subject(s) - interplanetary magnetic field , physics , dipole , flux (metallurgy) , magnetic flux , magnetic field , ionosphere , geophysics , solar wind , materials science , quantum mechanics , metallurgy
The interchange cycle is a mode of magnetic flux circulation that dominates when the interplanetary magnetic field (IMF) clock angle (θ c ≡ atan2( B Y , B Z )) lies in the range of ∣θ c ∣ 30°. It consists of IMF‐lobe reconnection in one hemisphere and lobe‐closed reconnection in the other hemisphere, producing in the ionosphere an interchange‐type merging cell in the former hemisphere and a reciprocal cell in the latter hemisphere. For a given IMF clock angle and a given dipole tilt angle, there usually exist two independent interchange cycles. Thus the two interchange cycles drive twin reverse cells in both hemispheres, but the category of each reverse cell (either an interchange‐type merging cell or a reciprocal cell) depends on the given conditions. In this paper, we demonstrate how the reverse cell pattern changes systematically depending on the IMF orientation and the dipole tilt.