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arXiv · 1403.1443

Electron production by solar Ly-{\alpha} line radiation in the ionospheric D-region

Aleksandra Nina·Vladimir M. Čadež
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Abstract

The hydrogen Ly-{\alpha} line has a dominant influence in photo-ionization processes in the unperturbed terrestrial ionospheric D region. In this paper, we present a procedure of calculating the rate of photo-ionization induced by Ly-{\alpha} photons based on relaxation of electron density after intensive perturbations like those caused by solar X flares. This theory is applied to the ends of relaxation periods following three cases of solar X flares from May 5, 2010, February 18, 2011 and March 24, 2011. The necessary data on low ionospheric plasma parameters were collected by the very low frequency (VLF) radio-wave technics. The electron concentration is calculated from the amplitude and phase of the VLF signal emitted by the DHO transmitter in Germany and recorded by a receiver located in Serbia.

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Aleksandra Nina, Vladimir M. Čadež. 2014-03-06. Electron production by solar Ly-{\alpha} line radiation in the ionospheric D-region. https://doi.org/10.1016/j.asr.2013.12.042

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