Different types of low‐latitude boundary layer as observed by Interball Tail probe

Вайсберг, О. Л.; Смирнов, В. Н.; Avanov, L. A.; Waite, J. H.; Burch, J. L.; Gallagher, D. L.; Бородкова, Н. Л.

doi:10.1029/2000ja000154

Cited by 21 publications

(21 citation statements)

References 70 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reported auroral fine structure on LLBL field lines is in line with recently reported in situ observations of the LLBL [ Vaisberg et al , 2001]. According to these observations, obtained from the Interball Tail probe, the LLBL during negative IMF B z conditions is highly structured and usually consists of short‐time (0.5–5 min) transients of magnetosheath‐like plasma within a background of more energetic magnetosphere plasma.…”

Section: Discussionsupporting

confidence: 87%

“…The magnetopause shows an open structure of a rotational discontinuity with strongly varying bidirectional electrons. According to Vaisberg et al [2001], there is evidence that the described events are associated with nonstationary reconnection. The auroral fine structure at the cusp equatorward boundary (EBIs) reported in this paper (Figures 2 and 3) most likely corresponds to this type of LLBL structure, which was found to be located on open field lines.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Auroral structure at the cusp equatorward boundary: Relationship with the electron edge of low‐latitude boundary layer precipitation

Sandholt

Denig

Farrugia

et al. 2002

Journal of Geophysical Research: Space Physics

View full text Add to dashboard Cite

We document the correspondence between different categories of auroral forms/activities and particle precipitation/plasma convection regimes in the 1100–1300 MLT/70°–77° MLAT sector during strongly negative interplanetary magnetic field By (−7 nT) and smaller (2 to −4 nT) Bz conditions. Ground observations of the aurora are combined with data from two overflights by the spacecraft DMSP F11 and F12 on 8 January 1999. We describe the dynamics of the aurorae in the midday sector corresponding to the particle precipitation regimes which in the literature are designated (1) the dayside extension of the central plasma sheet, (2) void, (3) the electron edge, (4) the low‐latitude boundary layer (LLBL), and (5) the plasma mantle. The aurorae observed in the corresponding latitude regimes are the following: (1) the pulsating, diffuse, green line‐dominated plasma sheet aurora (type 3), (2) a ∼100 km wide latitudinal gap in auroral emission, (3) and (4) the type 1 cusp aurora characterized by recurrent (T = 2–3 min) equatorward boundary intensifications (EBIs), and (5) poleward moving auroral forms. Special focus is placed on (1) the association between EBIs and the electron edge/ion cutoff observed at the equatorward boundary of the LLBL precipitation and (2) the gap in the auroral emission profile located on its equatorward side. The latter corresponds to the observed strongly depleted field–aligned electron fluxes (void), which in our view is due to the loss of plasma sheet particles along newly opened field lines. Thus, in this case study we document the auroral fine structure corresponding to the open LLBL, with its electron edge, as well as the signature of the escape of magnetospheric electrons along the adjacent field lines on its equatorward/inward side.

show abstract

Section: Discussionsupporting

confidence: 87%

Section: Discussionmentioning

confidence: 99%

Auroral structure at the cusp equatorward boundary: Relationship with the electron edge of low‐latitude boundary layer precipitation

Sandholt

Denig

Farrugia

et al. 2002

Journal of Geophysical Research: Space Physics

View full text Add to dashboard Cite

show abstract

“…Lundin and Evans, 1985;Phan et al, 1997;Vaisberg et al, 2001). The total variation of the bulk velocity across the layer is limited for this class of events by the solar wind convection velocity.…”

Section: Introductionmentioning

confidence: 99%

Sheared magnetospheric plasma flows and discrete auroral arcs: a quasi-static coupling model

Echim

Roth²,

Keyser³

2007

Ann. Geophys.

View full text Add to dashboard Cite

Abstract. We consider sheared flows in magnetospheric boundary layers of tangential discontinuity type, forming a structure that is embedded in a large-scale convergent perpendicular electric field. We construct a kinetic model that couples the magnetospheric structure with the topside ionosphere. The contribution of magnetospheric electrons and ionospheric electrons and ions is taken into account into the current-voltage relationship derived for an electric potential monotonically decreasing with the altitude. The solution of the current continuity equation gives the distribution of the ionospheric potential consistent with the given magnetospheric electric potential. The model shows that a sheared magnetospheric flow generates current sheets corresponding to upward field-aligned currents, field-aligned potential drops and narrow bands of precipitating energy, as in discrete auroral arcs. Higher velocity magnetospheric sheared flows have the tendency to produce brighter and slightly broader arcs. An increase in arc luminosity is also associated with enhancements of magnetospheric plasma density, in which case the structures are narrower. Finally, the model predicts that an increase of the electron temperature of the magnetospheric flowing plasma corresponds to slightly wider arcs but does not modify their luminosity.

show abstract

“…There are some signatures in the magnetosheath, indicating that reconnection is going on: magnetospheric ion leakage events (seen as the bursts at higher energies in the anti-sunward-looking analyzer) accompanied by stronger velocity and magnetic field variations (see Vaisberg et al, 1998Vaisberg et al, , 2001. Figure 2 shows LLBL structures observed by Interball after the magnetopause crossing.…”

Section: Characteristics Of Observed Llbl On 15 February 1996mentioning

confidence: 99%

Ion velocity distributions within the LLBL and their possible implication to multiple reconnections

et al. 2004

Self Cite

View full text Add to dashboard Cite

Abstract. We analyze two LLBL crossings made by the Interball-Tail satellite under a southward or variable magnetosheath magnetic field: one crossing on the flank of the magnetosphere, and another one closer to the subsolar point. Three different types of ion velocity distributions within the LLBL are observed: (a) D-shaped distributions, (b) ion velocity distributions consisting of two counterstreaming components of magnetosheath-type, and (c) distributions with three components, one of which has nearly zero parallel velocity and two counter-streaming components. Only the (a) type fits to the single magnetic flux tube formed by reconnection between the magnetospheric and magnetosheath magnetic fields. We argue that two counterstreaming magnetosheath-like ion components observed by Interball within the LLBL cannot be explained by the reflection of the ions from the magnetic mirror deeper within the magnetosphere. Types (b) and (c) ion velocity distributions would form within spiral magnetic flux tubes consisting of a mixture of alternating segments originating from the magnetosheath and from magnetospheric plasma. The shapes of ion velocity distributions and their evolution with decreasing number density in the LLBL indicate that a significant part of the LLBL is located on magnetic field lines of long spiral flux tube islands at the magnetopause, as has been proposed and found to occur in magnetopause simulations. We consider these observations as evidence for multiple reconnection Xlines between magnetosheath and magnetospheric flux tubes.

show abstract

Different types of low‐latitude boundary layer as observed by Interball Tail probe

Cited by 21 publications

References 70 publications

Auroral structure at the cusp equatorward boundary: Relationship with the electron edge of low‐latitude boundary layer precipitation

Auroral structure at the cusp equatorward boundary: Relationship with the electron edge of low‐latitude boundary layer precipitation

Sheared magnetospheric plasma flows and discrete auroral arcs: a quasi-static coupling model

Ion velocity distributions within the LLBL and their possible implication to multiple reconnections

Contact Info

Product

Resources

About