Open AccessQuasi-periodic precipitation with periods between 40 and 60 minutes
Author(s) -
K. Rinnert
Publication year - 1996
Publication title -
annales geophysicae
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.522
H-Index - 93
eISSN - 1432-0576
pISSN - 0992-7689
DOI - 10.1007/s00585-996-0707-1
Subject(s) - incoherent scatter , earth's magnetic field , quiet , electron precipitation , physics , atmospheric sciences , electron density , ionosphere , morning , flux (metallurgy) , geophysics , precipitation , electric field , electron , magnetic field , meteorology , computational physics , magnetosphere , materials science , astronomy , quantum mechanics , metallurgy
Intervals of periodic enhancements of\udE-region electron density have been found in EISCAT (European Incoherent SCATter)\uddata. The periods are typically between 40 and 60 min. The phenomenon is\udobserved during relatively quiet times, though after geomagnetic disturbances;\udit may last up to 6 h. The events can occur at all times of day with a maximum\udprobability in the MLT morning sector. Using the EISCAT database from recent\udyears, the statistical characteristics of these events, and their relation to\udmagnetospheric conditions defined by the Dst index and the d.c. electric field\udperpendicular to B\= have been derived. The latitudinal extent is found to be\udseveral degrees, but the longitudinal extent is not known. It is concluded that\udthese events are due to the periodically modulated flux of electron\udprecipitation controlled by oscillations in the magnetospheric tail