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2003-2004 Publications of
SGO, Oulu unit
Physicist Alexander Kozlovsky
Space physics
The magnetosphere-ionosphere electrodynamics inferred from the radar
and optical observations
The studies are related to one of the most important issues of
solar-terrestrial physics that is the mechanisms of the energy and momentum
transferring from the solar wind into the Earth's magnetosphere and
ionosphere. The energy penetration occurs in the high-latitude dayside
magnetosphere in the course of solar wind - magnetosphere interaction and
leads to a variety of phenomena in the magnetospheric electromagnetic
fields, plasma, and particle distributions.
The main product of the solar wind - magnetosphere coupling is the
large-scale convection of the magnetospheric plasma. In the outer
magnetosphere, the solar wind drives the plasma antisunward, and return flow
occurs in the inner magnetosphere. The magnetospheric convection is mapped
along magnetic field lines into the ionosphere. In the ionosphere, the
convection can be observed by radars. The EISCAT (http://www.eiscat.com/)
incoherent scatter radar systems in Tromsø-Kiruna-Sodankylä (UHF)
(http://www.eiscat.com/tromso.html), Tromsø (VHF), and Svalbard (UHF) together with the
CUTLASS (http://ion.le.ac.uk/cutlass
) radar system provide a large
amount of experimental data on the plasma flows in the high-latitude ionosphere.
The other result of the solar wind-magnetosphere interaction is that the
magnetosphere contains the hot plasma (energies in the keV range) coming
from the solar wind or heated inside the magnetosphere due to
transformations of the convection energy (acceleration and heating in the
magnetotail). Precipitation of the high-energy particles creates auroras.
The auroral phenomena are visible manifestations of the magnetospheric
processes, which can be observed by ground based all-sky cameras
(http://www.sgo.fi/Data/RealTime/
allsky.php). Cameras onboard satellites can observe
a global auroral distribution (e.g., Polar satellite project
(http://www.ess.washington.
edu/Space/
SpaceExp/POLAR/)).
The radar measurements combined with the auroral observations allow
monitoring of the magnetospheric dynamics. Also, these experiments allow
investigation of the key problems of the plasma physics.
Publications
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