Anthropogenic electromagnetic emissions in the Earth’s magnetosphere

Advisor: František Němec (DSPS FMF CUNI)

Funding: Fully funded

Website: http://nemec.matfyz.cz

Contact: frantisek.nemec@mff.cuni.cz

Very low frequency (i.e., up to about 20 kHz) anthropogenic electromagnetic emissions (primarily power line harmonic radiation and signals from powerful military transmitters) can – after propagating some distance in the Earth-ionosphere waveguide – escape to the space. There they can be detected by spacecraft, not only close to a given wave source, but along the entire respective magnetic field line and eventually also in the magnetically conjugated region. These waves are important both with regard to their interaction with energetic particles trapped in the Van Allen radiation belts and considering newly generated (“triggered”) emissions which would not occur otherwise.

The aim of the study is to use available low-altitude spacecraft data (DEMETER, prospectively TARANIS) as well as measurements at larger radial distances (Cluster, Van Allen Probes) for the experimental analysis of these emissions. The focus will be on their overall intensities and variations due to geomagnetic activity, means of propagation throughout the inner magnetosphere, and the evaluation of optimal conditions for the generation of triggered emissions and their properties. A particular attention will be also paid to related energetic electron precipitation and ionospheric changes.

This is a project focused on an analysis of existing satellite (and to a lesser extent possibly also ground-based) data. It involves programming of dedicated data analysis procedures and a scientific interpretation of the results obtained.

Literature:

[1] M. G. Kivelson, C. T. Russell: Introduction to Space Physics. University Press, Cambridge, 1995.
[2] M. Golkowski, V. Harid, P. Hosseini: Review of Controlled Excitation of Non-Linear Wave-Particle Interactions in the Magnetosphere. Front. Astron. Space Sci., 2019.
[3] H. Volland: Handbook of Atmospheric Electrodynamics, Volume II. CRC Press, Boca Raton, 1995.