Ionospheric Feedback and ULF Quarter?Waves
نویسندگان
چکیده
This paper presents results from the numerical investigation of nonlinear feedback interactions between ULF field-aligned currents (FACs) and ionospheric plasma in global magnetospheric resonator with a non-symmetrical distribution density conjugate hemispheres. The asymmetry is enhanced by introduction valley hemisphere where already lower. main result this study that resonator, mechanism, driven electric field maximum amplitude 50 mV/m, develops nonlinear, intense, small-scale upward characteristic quarter-wavelength structure along ambient magnetic field. frequency these waves two times less than fundamental symmetrical resonator. valleys, which are depletions E F regions, enhance effect, reducing effective conductivity. effect important for interpretation ground, satellite, sounding rocket observations FACs auroral subauroral geospace.
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ژورنال
عنوان ژورنال: Journal Of Geophysical Research: Space Physics
سال: 2022
ISSN: ['2169-9402', '2169-9380']
DOI: https://doi.org/10.1029/2022ja030659