Theory of X-Ray Emissions in Solar Flaring Loops

  • Guangli HuangEmail author
  • Victor F. Melnikov
  • Haisheng Ji
  • Zongjun Ning


X-rays are one of the important way to observe and study the solar flares which are able to radiate the emissions with a wide spectrum. Observationally, the soft and hard X-rays are dependent on the energy, the low and high bands respectively. Physically, the former is related with the thermal plasma, while the latter is produced by the NT electrons. Therefore, the solar flares show smoothed light curves of SXRs, but many spikes or sub-peaks with a short timescale (down to 10 milliseconds dependence on the time resolution of the instruments) are superposed on the HXR light curves. From the spatial topology, the solar flares usually display a loop system, and the SXRs are bright of the whole loop, while the HXRs exhibit an LT and double FP sources associated with it. The observations with a broad dynamic energy range and a high sensitivity provide the second coronal source , named the above-the-LT source during the solar flare.


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Copyright information

© Science Press, Beijing and Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  • Guangli Huang
    • 1
    Email author
  • Victor F. Melnikov
    • 2
  • Haisheng Ji
    • 1
  • Zongjun Ning
    • 1
  1. 1.Purple Mountain ObservatoryNanjingChina
  2. 2.Pulkovo ObservatoryRussian Academy of SciencesSaint-PetersburgRussia

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