Cluster is an ongoing ESA mission launched in 2000 and expected to deliver science data at least until the
end of 2017. Consisting from four identical spacecraft flying in close tetrahedral formation through key
regions of the Terrestrial magnetosphere, it allows for the first time a truly three-dimensional view of the
fundamental physical processes taking place in the plasma environment surrounding the Earth.
One of the eleven instruments onboard each spacecraft is the Flux Gate Magnetometer
(FGM)
which provides high resolution measurements of the three components of the magnetic field. To be used, the raw
FGM data must first be calibrated. Because calibrated magnetic field data are necessary for data processing
and calibration of other instruments onboard, quick delivery of FGM calibration parameters is of utmost
importance. The daily calibration provides sets of calibration parameters valid for one entire day for each
day of the mission.
Due to changes in the orbit, in the last years the complexity of this task has increased substantially and a
more automatic calibration strategy is desirable. Using the current calibration software, TUNED provides
an user-friendly, well documented software environment to automate most of the time-consuming parts of
the calibration process. The project also contributes to the production of daily calibration files.
The calibration activity benefits from the collaboration with the
FGM calibration team
at the Technical
University of Braunschweig and it is based on existing and tested software and techniques developed before
the Cluster launch and during its mission.
Giving that Cluster provides a three-dimensional view of the magnetic field, its measurements are especially
well fitted for the study of nonstationary events taking place at the Earth bowshock. One area which still
requires more attention is the electron acceleration and heating in the shock layer. TUNED proposes the
study of the electron dynamics in the bowshock taking advantage of the high accuracy Cluster
measurements. Theoretical treatment and state of the art numerical simulations will complement the
analyses of the experimental data. The electron distribution functions and the deHoffmann-Teller cross
shock potential will be evaluated and compared with the Liouville Vlasov theory expectations.
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