Electromagnetic Thermal Noise in Upper-Hybrid Frequency Range

Author
Keywords
Abstract
<p>The inner magnetosphere including the radiation belt and ring current environment is replete with high-frequency fluctuations with peak intensity occurring near upper-hybrid frequency and/or multiple harmonic electron cyclotron frequencies above and below the upper-hybrid frequency. Past and contemporary spacecraft missions, including the Van Allen Probes, were designed to detect the electric field spectrum only for these high-frequency fluctuations. Making use of the recently formulated generalized theory of electromagnetic spontaneous emission in thermal magnetized plasmas, it is shown that upper-hybrid/multiple harmonic electron cyclotron emissions are characterized by a significant magnetic field component, even in the high-frequency regime. Such a prediction may potentially be tested by upcoming spacecraft missions including the Solar Probe Orbiter and Parker Solar Probe. The present finding may also have a potentially significant ramification for the broader astrophysical contexts.</p>
Year of Publication
2018
Journal
Journal of Geophysical Research: Space Physics
Volume
123835101204457272221044751983242776841205998122321002852287122242455
Number of Pages
5356-5363
Date Published
07/2018
URL
http://onlinelibrary.wiley.com/wol1/doi/10.1029/2018JA025459/fullpdf
DOI
10.1029/2018JA025459