X-ray source effect on VLF radiation diurnal period amplitude

Druzhin G.I., Mel'nikov A.N., Cherneva N.V.
  1. Institute of Cosmophysical Researches and Radio Wave Propagation FEB RAS, Russia

   On the basis of observation data at "Karymshina" and "Paratunka" sites
   (Kamchatka), spectral analysis of natural VLF noise envelope for the
   frequencies of 0.7, 1.2, 5.3 kHz for 1997 - 2006 and of pulse radiation
   (atmospherics) in the frequency band of 3 - 60 кГц for 2002 - 2006 was
   carried out. It has been shown, that in noise and pulse components there
   are diurnal maxima, which coincide with the Eath rotation periods relative
   to the Sun (1440 min) and relative to stars (1436 min). It has been
   concluded, that not only the Sun X-ray radiation but also the Galaxy X-ray
   radiation may affect the level of ionization of ionosphere D layer.