An explanation for tailward flows with positive B{sub z} in the distant tail neutral sheet during quiet times

Journal Article · Thu Dec 15 04:00:00 EST 1994 · Geophysical Research Letters

DOI:https://doi.org/10.1029/94GL02097· OSTI ID:70496

Lyons, L R; Pridmore-Brown, D C ^[1]

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1. Aerospace Corp., Los Angeles, CA (United States)

ISEE-3 and GEOTAIL observations have revealed that at x = {minus}210 to {minus}220 R{sub E}, the z-component of magnetic field across the tail neutral sheet is positive, and the plasma flow is tailward during geomagnetically quiet times. Observations have also show that the y- and z-components of the interplanetary magnetic field (IMF) partially penetrate into the magnetotail for both positive and negative IMF B{sub z}. The authors have evaluated the topology of the magnetospheric magnetic field expected from a partial penetration of the IMF when it has a positive z-component. They find that, in addition to the closed and purely IMF field lines that are generally acknowledged to exist for a southward IMF B{sub z}, there is a region at intermediate radial distances of open field lines that cross the tail neutral sheet before existing the magnetosphere. This region lies between x {approx} {minus}150 R{sub E} and x {approx} {minus}325 R{sub E} for the representative IMF orientation and model that they have used. The authors suggest that the quiet-time observations from ISEE-3 and GEOTAIL of tailward flow and positive B{sub z} across the distant tail neutral sheet were obtained during positive IMF B{sub z} conditions and in the region of open field lines. Such an explanation would also account for the GEOTAIL observation that magnetosheath-like plasma associated with positive B{sub z} is common in the distant tail plasma sheet beyond 150 R{sub E} but not closer to the Earth. 17 refs., 1 fig.

• OSTI ID: 70496
• Journal Information: Geophysical Research Letters, Journal Name: Geophysical Research Letters Journal Issue: 25 Vol. 21; ISSN GPRLAJ; ISSN 0094-8276
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
INTERPLANETARY MAGNETIC FIELDS
MAGNETOTAIL
ORIENTATION
PLASMA DRIFT