Statistical study of the late substorm recovery phase and quiet time plasma sheet based on ISEE 1 ∼30-keV ion observations

1994 ◽  
Vol 99 (A6) ◽  
pp. 10981 ◽  
Author(s):  
D. P. Traver ◽  
D. G. Mitchell ◽  
D. J. Williams
Keyword(s):  
Plasma Sheet ◽  
Statistical Study ◽  
Recovery Phase ◽  
Quiet Time

Observational determination of the adiabatic index in the quiet time plasma sheet

1989 ◽  
Vol 16 (6) ◽  
pp. 563-566 ◽  
Author(s):  
C. Y. Huang ◽  
C. K. Goertz ◽  
L. A. Frank ◽  
G. Rostoker
Keyword(s):  
Plasma Sheet ◽  
Adiabatic Index ◽  
Quiet Time

The Variation of Ionospheric O+ and H+ Outflow during Sawtooth Oscillations

2021 ◽  
Author(s):  
Niloufar Nowrouzi ◽  
Lynn Kistler ◽  
Eric Lund ◽  
Kai Zhao
Keyword(s):  
Plasma Sheet ◽  
Statistical Study ◽  
Onset Time ◽  
Direct Access ◽  
Data Set ◽  
Superposed Epoch Analysis ◽  
3D Data ◽  
Before And After ◽  
Epoch Analysis ◽  
Sawtooth Oscillations

<p>Sawtooth events are repeated injections of energetic particles at geosynchronous orbit. Although studies have shown that 94% of sawtooth events occur during  magnetic storm times, the main factor that causes a sawtooth event is unknown. Simulations have suggested that heavy ions like O<sup>+</sup> may play a role in driving the sawtooth mode by increasing the magnetotail pressure and causing the magnetic tail to stretch. O<sup>+</sup> ions located in the nightside auroral region have a direct access to the near-earth plasma-sheet. O<sup>+</sup> in the dayside cusp can reach to the midtail plasma-sheet when the convection velocity is sufficiently strong. Whether the dayside or nightside source is more important is not known.</p><p>We show results of a statistical study of the variation of the O+ and H+ outflow flux during sawtooth events for SIR and ICME sawtooth events. We perform a superposed epoch analysis of the ion outflow using the TEAMS (Time-of-Flight Energy Angle Mass Spectrograph) instrument on the FAST spacecraft. TEAMS measures the ion composition over the energy range of 1 eV e<sup>-1</sup> to 12 keV e<sup>-1</sup>.  We have done major corrections and calibrations (producing 3D data set, anode calibration, mass classification, removing ram effect and incorporating dead time corrections) on TEAMS data and produced a data set for four data species (H<sup>+</sup>, O<sup>+</sup>, and He<sup>+</sup>). From 1996 to 2007, we have data for 133 orbits of CME-driven and for 103 orbits of SIR-driven sawtooth events with an altitude above 1500 km. We found that:</p><ul><li>the averaged O<sup>+</sup> outflow flux is more intense in the cusp dayside than in the nightside, before and after onset time.</li> <li><span>Before onset, an intense averaged outflow flux in the dawnside of CME events is seen. This outflow decreases after onset time.</span></li> <li><span>In both CME-driven and SIR-driven, the averaged O</span><sup>+</sup><span> outflow increases after onset time, in the nightside, cusp dayside. This increase is greater on the nightside than in the cusp.</span></li> </ul><p>We will develop this study by performing a similar statistical study for H<sup>+</sup> outflow and finally will compare the H<sup>+</sup> result with the O<sup>+ </sup>result.</p>

scholarly journals A statistical study of the inner edge of the electron plasma sheet and the net convection potential as a function of geomagnetic activity

2011 ◽  
Vol 116 (A6) ◽  
pp. n/a-n/a ◽  
Author(s):  
F. Jiang ◽  
M. G. Kivelson ◽  
R. J. Walker ◽  
K. K. Khurana ◽  
V. Angelopoulos ◽  
...  
Keyword(s):  
Geomagnetic Activity ◽  
Plasma Sheet ◽  
Statistical Study ◽  
Electron Plasma

Quiet-time convection electric field properties derived from keV electron measurements at the inner edge of the plasma sheet by means of GEOS-2

1982 ◽  
Vol 30 (3) ◽  
pp. 261-283 ◽  
Author(s):  
B. Hultqvist ◽  
H. Borg ◽  
L.-Ă. Holmgren ◽  
H. Reme ◽  
A. Bahnsen ◽  
...  
Keyword(s):  
Electric Field ◽  
Plasma Sheet ◽  
Quiet Time ◽  
Convection Electric Field

INTERBALL statistical study of ion flow fluctuations in the plasma sheet

2002 ◽  
Vol 30 (12) ◽  
pp. 2695-2700 ◽  
Author(s):  
Yu.I Yermolaev ◽  
A.A Petrukovich ◽  
L.M Zelenyi
Keyword(s):  
Plasma Sheet ◽  
Statistical Study ◽  
Ion Flow ◽  
Flow Fluctuations

scholarly journals Modeling the quiet time inner plasma sheet protons

2001 ◽  
Vol 106 (A4) ◽  
pp. 6161-6178 ◽  
Author(s):  
Chih-Ping Wang ◽  
Larry R. Lyons ◽  
Margaret W. Chen ◽  
Richard A. Wolf
Keyword(s):  
Plasma Sheet ◽  
Quiet Time

scholarly journals An auroral westward flow channel (AWFC) and its relationship to field-aligned current, ring current, and plasmapause location determined using multiple spacecraft observations

2007 ◽  
Vol 25 (1) ◽  
pp. 59-76 ◽  
Author(s):  
M. L. Parkinson ◽  
J. A. Wild ◽  
C. L. Waters ◽  
M. Lester ◽  
E. A. Lucek ◽  
...  
Keyword(s):  
Plasma Sheet ◽  
Large Scale ◽  
Ring Current ◽  
Narrow Channel ◽  
Recovery Phase ◽  
Global Scale ◽  
Auroral Oval ◽  
Flow Channel ◽  
Expansion Phase ◽  
Field Aligned Current

Abstract. An auroral westward flow channel (AWFC) is a latitudinally narrow channel of unstable F-region plasma with intense westward drift in the dusk-to-midnight sector ionosphere. AWFCs tend to overlap the equatorward edge of the auroral oval, and their life cycle is often synchronised to that of substorms: they commence close to substorm expansion phase onset, intensify during the expansion phase, and then decay during the recovery phase. Here we define for the first time the relationship between an AWFC, large-scale field-aligned current (FAC), the ring current, and plasmapause location. The Tasman International Geospace Environment Radar (TIGER), a Southern Hemisphere HF SuperDARN radar, observed a jet-like AWFC during ~08:35 to 13:28 UT on 7 April 2001. The initiation of the AWFC was preceded by a band of equatorward expanding ionospheric scatter (BEES) which conveyed an intense poleward electric field through the inner plasma sheet. Unlike previous AWFCs, this event was not associated with a distinct substorm surge; rather it occurred during an interval of persistent, moderate magnetic activity characterised by AL~−200 nT. The four Cluster spacecraft had perigees within the dusk sector plasmasphere, and their trajectories were magnetically conjugate to the radar observations. The Waves of High frequency and Sounder for Probing Electron density by Relaxation (WHISPER) instruments on board Cluster were used to identify the plasmapause location. The Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) EUV experiment also provided global-scale observations of the plasmapause. The Cluster fluxgate magnetometers (FGM) provided successive measurements specifying the relative location of the ring current and filamentary plasma sheet current. An analysis of Iridium spacecraft magnetometer measurements provided estimates of large-scale ionospheric FAC in relation to the AWFC evolution. Peak flows in the AWFC were located close to the peak of a Region 2 downward FAC, located just poleward of the plasmapause. DMSP satellite observations confirmed the AWFC was located equatorward of the nightside plasmasheet, sometimes associated with ~10 keV ion precipitation.

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