Electron fluxes in the near-Earth magnetotail

Citation
O. Santolik et al., Electron fluxes in the near-Earth magnetotail, CZEC J PHYS, 49(4A), 1999, pp. 607-624
Citations number
19
Categorie Soggetti
Physics
Journal title
CZECHOSLOVAK JOURNAL OF PHYSICS
ISSN journal
00114626 → ACNP
Volume
49
Issue
4A
Year of publication
1999
Pages
607 - 624
Database
ISI
SICI code
0011-4626(199904)49:4A<607:EFITNM>2.0.ZU;2-I
Abstract
In the geomagnetic tail, enhanced electron fluxes are observed mainly in th e plasma sheet and in the plasma sheet boundary layer. We use the data of t he Interball-tail probe to study the regions of electron fluxes across the near-Earth magnetotail, up to the distances of 30 R-E. The Interball orbit allows us to scan the tail in both Y-GSM and Z(GSM) coordinates, from low t o high latitudes. The spatial distribution of enhanced electron fluxes has been statistically estimated using the data collected during more than 2 ye ars of satellite operation. We have found two basic regions of occurrence: (1) As expected, with a nearly 100% occurrence rate, the electron fluxes ha ve been found in the plasma sheet region, up to 3-4 R-E above the neutral s heet in the central part and up to 7-8 R-E above the neutral sheet near the low-latitude boundary layer; (2) with about 10% occurrence rate, we observ e enhanced electron fluxes near the high-latitude magnetopause. In each of these regions, we present a case study based on two point measurements onbo ard both main satellite and subsatellite. We characterize ion and electron plasma components and motion of observed boundaries. Low-latitude case can be interpreted as irregular flapping of the plasma sheet and its boundary l ayer. Near the high-latitude magnetopause, the case study shows isolated pl asma structures having the size comparable to the Earth's radius and moving with a velocity from several km/s up to several tens of km/s. These struct ures contain electrons with energies of several hundreds of eV, and their n ature remains unclear.