Compressible turbulence with slow-mode waves observed in the bursty bulk flow of plasma sheet

Abstract. On 07 September 2001 the Cluster spacecraft observed a "bursty bulk flow" event in the near-Earth central plasma sheet. This paper presents a detailed study of the coincident ground-based observations and attempts to place them within a simple physical framework. The event in question occurs at ~22:30 UT, some 10min after a southward turning of the IMF. IMAGE and SAMNET magnetometer measurements of the ground magnetic field reveal perturbations of a few tens of nT and small amplitude Pi2 pulsations. CUTLASS radar observations of ionospheric plasma convection show enhanced flows out of the polar cap near midnight, accompanied by an elevated transpolar voltage. Optical data from the IMAGE satellite also show that there is a transient, localised ~1 kR brightening in the UV aurora. These observations are consistent with the earthward transport of plasma in the tail, but also indicate the absence of a typical "large-scale" substorm current wedge. An analysis of the field-aligned current system implied by the radar measurements does suggest the existence of a small-scale current "wedgelet", but one which lacks the global scale and high conductivities observed during substorm expansions. Key words. Ionosphere (auroral ionosphere; ionospheremagnetosphere interactions; plasma convection)

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Bursty Bulk Flow Driven Turbulence in the Earth’s Plasma Sheet

Space Science Reviews ◽

10.1007/s11214-006-6987-7 ◽

2006 ◽

Vol 122 (1-4) ◽

pp. 301-311 ◽

Cited By ~ 31

Author(s):

Z. Vörös ◽

W. Baumjohann ◽

R. Nakamura ◽

M. Volwerk ◽

A. Runov

Keyword(s):

Plasma Sheet ◽

Bulk Flow ◽

Bursty Bulk Flow

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Large-amplitude electric fields associated with bursty bulk flow braking in the Earth's plasma sheet

Journal of Geophysical Research Space Physics ◽

10.1002/2014ja020165 ◽

2015 ◽

Vol 120 (3) ◽

pp. 1832-1844 ◽

Cited By ~ 46

Author(s):

R. E. Ergun ◽

K. A. Goodrich ◽

J. E. Stawarz ◽

L. Andersson ◽

V. Angelopoulos

Keyword(s):

Electric Fields ◽

Plasma Sheet ◽

Large Amplitude ◽

Bulk Flow ◽

Bursty Bulk Flow

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Spectral scaling in the turbulent Earth's plasma sheet revisited

Nonlinear Processes in Geophysics ◽

10.5194/npg-14-535-2007 ◽

2007 ◽

Vol 14 (4) ◽

pp. 535-541 ◽

Cited By ~ 25

Author(s):

Z. Vörös ◽

W. Baumjohann ◽

R. Nakamura ◽

A. Runov ◽

M. Volwerk ◽

...

Keyword(s):

Magnetic Reconnection ◽

Plasma Sheet ◽

Large Scale ◽

Spatial Scales ◽

Inertial Range ◽

Bulk Flow ◽

Magnetic Fluctuations ◽

Magnetohydrodynamic Turbulence ◽

Multi Scale ◽

Bursty Bulk Flow

Abstract. Bursty bulk flow associated magnetic fluctuations exhibit at least three spectral scaling ranges in the Earth's plasma sheet. Two of the three scaling ranges can be associated with multi-scale magnetohydrodynamic turbulence between the spatial scales from ~100 km to several RE (RE is the Earth's radius). These scales include the inertial range and below ~0.5 RE a steepened scaling range, theoretically not fully understood yet. It is shown that, in the near-Earth plasma sheet, the inertial range can be robustly identified only if multi-scale quasi stationary (MSQS) data intervals are selected. Multiple bursty flow associated magnetic fluctuations, however, exhibit 1/f type scaling indicating that large-scale fluctuations are controlled by multiple uncorrelated driving sources of the bulk flows (e.g. magnetic reconnection, instabilities).

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