OBSERVATION OF TWEEK-ATMOSPHERICS AFTER SOLAR FLARES AT THE "AKADEMIK VERNADSKY" UKRAINIAN ANTARCTIC STATION ...

• Main Author: Gorishnya Yu.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Sciences of Europe 2023
• Subjects: lower ionosphere diagnostic, ELF – VLF radiowaves, tweek-atmospherics, lightning location.; Antarc*; Antarctic
• Online Access: https://dx.doi.org/10.5281/zenodo.10081935; https://zenodo.org/doi/10.5281/zenodo.10081935

Tweek-atmospherics (tweeks), along with radio transmission by VLF radio stations, are used to study the lower ionosphere. Electromagnetic pulse radiation, which has been excited by the lightning discharges, has a maximum spectral density at extra low frequencies range (ELF, 300...3000 Hz) and very low frequencies (VLF, 3...30 kHz). The Earth-ionosphere cavity serves as a waveguide for electromagnetic waves in these frequency ranges. On the spectrogram of the tweek, the initial part is a linearly polarized broadband signal, and then a number of individual harmonics are observed. Their instantaneous frequencies decrease, asymptotically approaching approximately multiples of the cutoff frequencies of the waveguide. The single position method for lightning location and estimation of the ELF wave's reflection heights in the lower ionosphere by tweeks has been implemented into the computational algorithm. The clusters with approximately the same azimuths and distances to sources which have been obtained during the ...