Solar Physics

, 293:64 | Cite as

Analysis of the Relationship Between the Solar X-Ray Radiation Intensity and the D-Region Electron Density Using Satellite and Ground-Based Radio Data

  • Aleksandra Nina
  • Vladimir M. Čadež
  • Jovan Bajčetić
  • Srdjan T. Mitrović
  • Luka Č. Popović
Earth-affecting Solar Transients
Part of the following topical collections:
  1. Earth-affecting Solar Transients


Increases in the X-ray radiation that is emitted during a solar X-ray flare induce significant changes in the ionospheric D region. Because of the numerous complex processes in the ionosphere and the characteristics of the radiation and plasma, the causal-consequential relationship between the X-ray radiation and ionospheric parameters is not easily determined. In addition, modeling the ionospheric D-region plasma parameters is very difficult because of the lack of data for numerous time- and space-dependent physical quantities. In this article we first give a qualitative analysis of the relationship between the electron density and the recorded solar X-ray intensity. After this, we analyze the differences in the relationships between the D-region response and various X-ray radiation properties. The quantitative study is performed for data observed on 5 May 2010 in the time period between 11:40 UT – 12:40 UT when the GOES 14 satellite detected a considerable X-ray intensity increase. Modeling the electron density is based on characteristics of the 23.4 kHz signal emitted in Germany and recorded by the receiver in Serbia.


Flares D region Electron density 



The authors thank the Ministry of Education, Science and Technological Development of the Republic of Serbia through the projects III 44002 176001, 176002 and 176004. This study is made within the COST project TD1403 and the VarSITI project. We are grateful to the anonymous referee for comments and suggestions that significantly improved our paper. The authors are also grateful to Maša Lakićević for help in calculations using CHIANTI model and Janet Machol for access to data related to GOES 14 satellite calibration. The data for this paper collected by the GOES 14 satellite are available at NOAA’s National Centers for Environmental information ( ). Requests for the VLF data can be directed to the corresponding author.

Disclosure of Potential Conflicts of Interest

The authors declare that they have no conflicts of interest.


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© Springer Science+Business Media B.V., part of Springer Nature 2018

Authors and Affiliations

  • Aleksandra Nina
    • 1
  • Vladimir M. Čadež
    • 2
  • Jovan Bajčetić
    • 3
  • Srdjan T. Mitrović
    • 3
  • Luka Č. Popović
    • 2
    • 4
  1. 1.Institute of PhysicsUniversity of BelgradeBelgradeSerbia
  2. 2.Astronomical ObservatoryBelgradeSerbia
  3. 3.University of DefenceMilitary AcademyBelgradeSerbia
  4. 4.Faculty of MathematicsUniversity of BelgradeBelgradeSerbia

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