Ionization effects from cosmic sources of x-rays in the lower atmosphere

  • D P Sharma
  • U R Rao
  • K Kasturirangan


Detectable ionization effects in the ionosphericD-region from individual, strong and steady x-ray sources such as Sco X-1 and transient x-ray sources such as Cet X-2 have been reported by us and many others previously based on the field strength and phase variations of the VLF data. As a follow up to these investigations, we have examined the integrated effects of many of the known x-ray sources discovered by UHURU, ANS, Ariel V and SAS-3 satellites, in order to understand the totality of their effects. These effects are examined in the present paper for 0° and +38° geographic latitudes corresponding to midnight conditions and for different times of the year. Such effects are compared, in turn, with those of the known steady sources responsible forD-region ionization such as Lyman-alpha and galactic cosmic radiations. The results are presented as profiles of electron production rates as a function of height. Our study leads to the conclusion that there should be detectable annual variations of the electron density which are pronounced around May-August. Further, the results of the computations on electron production rates corresponding to the spectacular x-ray nova A0620-00 are also included in the present paper.


D-region ionization x-ray sources x-ray nova 


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Copyright information

© Indian Academy of Sciences 1978

Authors and Affiliations

  • D P Sharma
    • 1
  • U R Rao
    • 1
  • K Kasturirangan
    • 1
  1. 1.ISRO Satellite CentreBangalore

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